NASA's historic B-52 mother ship carried the X-43A and its Pegasus booster rocket on a captive carry flight from Edwards Air Force Base Jan. 26, 2004. The X-43A and its booster remained mated to the B-52 throughout the two-hour flight, intended to check its readiness for launch. The hydrogen-fueled aircraft is autonomous and has a wingspan of approximately 5 feet, measures 12 feet long and weighs about 2,800 pounds.

NASA's historic B-52 mother ship carried the X-43A and its Pegasus booster rocket on a captive carry flight from Edwards Air Force Base Jan. 26, 2004. The X-43A and its booster remained mated to the B-52 throughout the two-hour flight, intended to check its readiness for launch. The hydrogen-fueled aircraft is autonomous and has a wingspan of approximately 5 feet, measures 12 feet long and weighs about 2,800 pounds.

NASA's historic B-52 mother ship carried the X-43A and its Pegasus booster rocket on a captive carry flight from Edwards Air Force Base Jan. 26, 2004. The X-43A and its booster remained mated to the B-52 throughout the two-hour flight, intended to check its readiness for launch. The hydrogen-fueled aircraft is autonomous and has a wingspan of approximately 5 feet, measures 12 feet long and weighs about 2,800 pounds.

Hitching a ride on the same B-52 mother ship that once launched X-15 research aircraft in the 1960s, NASA's X-43A scramjet and it's Pegasus booster rocket performed a captive carry evaluation flight from Edwards Air Force Base, California, January 26, 2004. The X-43 and it's booster remained mated to the B-52 throughout this mission, intended to check its readiness for launch. The hydrogen-fueled aircraft is autonomous and has a wingspan of approximately 5 feet, measures 12 feet long and weighs about 2,800 pounds.

Hitching a ride on the same B-52 mother ship that once launched X-15 research aircraft in the 1960s, NASA's X-43A scramjet and it's Pegasus booster rocket performed a captive carry evaluation flight from Edwards Air Force Base, California, January 26, 2004. The X-43 and it's booster remained mated to the B-52 throughout this mission, intended to check its readiness for launch. The hydrogen-fueled aircraft is autonomous and has a wingspan of approximately 5 feet, measures 12 feet long and weighs about 2,800 pounds.

The second X-43A hypersonic research aircraft and its modified Pegasus booster rocket left the runway, carried aloft by NASA's B-52B launch aircraft from the NASA Dryden Flight Research Center at Edwards Air Force Base, Calif., on March 27, 2004. About an hour later the Pegasus booster was launched from the B-52 to accelerate the X-43A to its intended speed of Mach 7.

The second X-43A hypersonic research aircraft and its modified Pegasus booster rocket left the runway, carried aloft by NASA's B-52B launch aircraft from the NASA Dryden Flight Research Center at Edwards Air Force Base, Calif., on March 27, 2004. About an hour later the Pegasus booster was launched from the B-52 to accelerate the X-43A to its intended speed of Mach 7.

The second X-43A hypersonic research aircraft and its modified Pegasus booster rocket left the runway, carried aloft by NASA's B-52B launch aircraft from the NASA Dryden Flight Research Center at Edwards Air Force Base, Calif., on March 27, 2004. About an hour later the Pegasus booster was launched from the B-52 to accelerate the X-43A to its intended speed of Mach 7.

Attached to the same B-52B mothership that once launched X-15 research aircraft in the 1960s, NASA's third X-43A performed a captive carry evaluation flight from Edwards Air Force Base, California on September 27, 2004. The X-43 remained mated to the B-52 throughout this mission, intended to check its readiness for launch scheduled later in the fall.

The third X-43A hypersonic research aircraft and its modified Pegasus booster rocket left the runway, carried aloft by NASA's B-52B launch aircraft from the NASA Dryden Flight Research Center at Edwards Air Force Base, California, on November 16, 2004. About an hour later the Pegasus booster was launched from the B-52 to accelerate the X-43A to its intended speed of Mach 10.

Attached to the same B-52B mothership that once launched X-15 research aircraft in the 1960s, NASA's third X-43A performed a captive carry evaluation flight from Edwards Air Force Base, California on September 27, 2004. The X-43 remained mated to the B-52 throughout this mission, intended to check its readiness for launch scheduled later in the fall.

The third X-43A hypersonic research aircraft, attached to a modified Pegasus booster rocket, was taken to launch altitude by NASA's B-52B launch aircraft from the NASA Dryden Flight Research Center at Edwards Air Force Base, California, on November 16, 2004. About an hour later the Pegasus booster was released from the B-52 to accelerate the X-43A to its intended speed of Mach 10.

The second X-43A hypersonic research aircraft and its modified Pegasus booster rocket left the runway, carried aloft by NASA's B-52B launch aircraft from the NASA Dryden Flight Research Center at Edwards Air Force Base, Calif., on March 27, 2004. About an hour later the Pegasus booster was launched from the B-52 to accelerate the X-43A to its intended speed of Mach 7.

The Pegasus air-launched space booster is carried aloft under the right wing of NASA's B-52 carrier aircraft on its first captive flight from the Dryden Flight Research Center, Edwards, California. The first of two scheduled captive flights was completed on November 9, 1989. Pegasus is used to launch satellites into low-earth orbits cheaply. In 1997, a Pegasus rocket booster was also modified to test a hypersonic experiment (PHYSX). An experimental "glove," installed on a section of its wing, housed hundreds of temperature and pressure sensors that sent hypersonic flight data to ground tracking facilities during the experiment’s flight.

A one-twentieth scale model of the X-15 originally suspended beneath the wing of a B-52 is observed by a scientist of the National Aeronautics and Space Administration (NASA) as it leaves the bomber model in tests to determine the release characteristics and drop motion of the research airplane. Caption: The aerodynamics of air launching the North American X-15 being investigated in the 300MPH Low Speed 7x10 Tunnel, about 1957. Photograph published in Engineer in Charge: A History of the Langley Aeronautical Laboratory, 1917-1958 by James R. Hansen. Page 366. Photograph also published in Sixty Years of Aeronautical Research 1917-1977 By David A. Anderton. A NASA publication. Page 49.

A one-twentieth scale model of the X-15 originally suspended beneath the wing of a B-52 is observed by a scientist of the National Aeronautics and Space Administration (NASA) as it leaves the bomber model in tests to determine the release characteristics and drop motion of the research airplane. Caption: The aerodynamics of air launching the North American X-15 being investigated in the 300MPH Low Speed 7x10 Tunnel, about 1957. Photograph published in Engineer in Charge: A History of the Langley Aeronautical Laboratory, 1917-1958 by James R. Hansen. Page 366. Photograph also published in Sixty Years of Aeronautical Research 1917-1977 By David A. Anderton. A NASA publication. Page 49.

Air Force test pilot Maj. Michael J. Adams stands beside X-15 ship number one. Adams was selected for the X-15 program in 1966 and made his first flight on Oct. 6, 1966. On Nov. 15, 1967, Adams made his seventh and final X-15 flight. The X-15 launched from the B-52, but during the ascent an electrical problem affected the X-15's control system. The aircraft crashed northwest of Cuddeback Lake, California, causing the death of Adams. He was posthumously awarded Air Force astronaut wings because his final flight exceeded 50 miles in altitude. Adams was the only pilot lost in the 199-flight X-15 program.

From December 10, 1966, until his retirement on February 27, 1976, Stanley P. Butchart served as Chief (later, Director) of Flight Operations at NASA's Flight Research Center (renamed on March 26, 1976, the Hugh L. Dryden Flight Research Center). Initially, his responsibilities in this position included the Research Pilots Branch, a Maintenance and Manufacturing Branch, and an Operations Engineering Branch, the last of which not only included propulsion and electrical/electronic sections but project engineers for the X-15 and lifting bodies. During his tenure, however, the responsibilities of his directorate came to include not only Flight Test Engineering Support but Flight Systems and Loads laboratories. Before becoming Chief of Flight Operations, Butchart had served since June of 1966 as head of the Research Pilots Branch (Chief Pilot) and then as acting chief of Flight Operations. He had joined the Center (then known as the National Advisory Committee for Aeronautics' High-Speed Flight Research Station) as a research pilot on May 10, 1951. During his career as a research pilot, he flew a great variety of research and air-launch aircraft including the D-558-I, D-558-II, B-29 (plus its Navy version, the P2B), X-4, X-5, KC-135, CV-880, CV-990, B-47, B-52, B-747, F-100A, F-101, F-102, F-104, PA-30 Twin Comanche, JetStar, F-111, R4D, B-720, and B-47. Although previously a single-engine pilot, he became the Center's principal multi-engine pilot during a period of air-launches in which the pilot of the air-launch aircraft (B-29 or P2B) basically directed the operations. It was he who called for the chase planes before each drop, directed the positioning of fire rescue vehicles, and released the experimental aircraft after ensuring that all was ready for the drop. As pilot of the B-29 and P2B, Butchart launched the X-1A once, the X-1B 13 times, the X-1E 22 times, and the D-558-II 102 times. In addition, he towed the M2-F1 lightweight lifting body 14 times behind an R4

CAPE CANAVERAL, Fla. – On Launch Pad 17-B at Cape Canaveral Air Force Station in Florida, the first half of the fairing is moved into place around NASA's Kepler spacecraft, atop the United Launch Alliance Delta II rocket. The fairing is a molded structure that fits flush with the outside surface of the rocket and forms an aerodynamically smooth nose cone, protecting the spacecraft during launch and ascent. The liftoff of Kepler aboard the Delta II rocket is currently targeted for launch in a window extending 10:49 to 10:52 p.m. EST March 6 from Pad 17-B. Kepler is designed to survey more than 100,000 stars in our galaxy to determine the number of sun-like stars that have Earth-size and larger planets, including those that lie in a star's "habitable zone," a region where liquid water, and perhaps life, could exist. If these Earth-size worlds do exist around stars like our sun, Kepler is expected to be the first to find them and the first to measure how common they are. Photo credit: NASA/Jack Pfaller

CAPE CANAVERAL, Fla. – On Launch Pad 17-B at Cape Canaveral Air Force Station in Florida, NASA's Kepler spacecraft, atop the United Launch Alliance Delta II rocket, waits for encapsulation in the fairing. The fairing is a molded structure that fits flush with the outside surface of the rocket and forms an aerodynamically smooth nose cone, protecting the spacecraft during launch and ascent. The liftoff of Kepler aboard the Delta II rocket is currently targeted for launch in a window extending 10:49 to 10:52 p.m. EST March 6 from Pad 17-B. Kepler is designed to survey more than 100,000 stars in our galaxy to determine the number of sun-like stars that have Earth-size and larger planets, including those that lie in a star's "habitable zone," a region where liquid water, and perhaps life, could exist. If these Earth-size worlds do exist around stars like our sun, Kepler is expected to be the first to find them and the first to measure how common they are. Photo credit: NASA/Jack Pfaller

The wingless, lifting body aircraft sitting on Rogers Dry Lake at what is now NASA's Dryden Flight Research Center, Edwards, California, from left to right are the X-24A, M2-F3 and the HL-10. The lifting body aircraft studied the feasibility of maneuvering and landing an aerodynamic craft designed for reentry from space. These lifting bodies were air launched by a B-52 mother ship, then flew powered by their own rocket engines before making an unpowered approach and landing. They helped validate the concept that a space shuttle could make accurate landings without power. The X-24A flew from April 17, 1969 to June 4, 1971. The M2-F3 flew from June 2, 1970 until December 22, 1972. The HL-10 flew from December 22, 1966 until July 17, 1970, and logged the highest and fastest records in the lifting body program.

The wingless, lifting body aircraft sitting on Rogers Dry Lake at what is now NASA's Dryden Flight Research Center, Edwards, California, from left to right are the X-24A, M2-F3 and the HL-10. The lifting body aircraft studied the feasibility of maneuvering and landing an aerodynamic craft designed for reentry from space. These lifting bodies were air launched by a B-52 mother ship, then flew powered by their own rocket engines before making an unpowered approach and landing. They helped validate the concept that a space shuttle could make accurate landings without power. The X-24A flew from April 17, 1969 to June 4, 1971. The M2-F3 flew from June 2, 1970 until December 21, 1971. The HL-10 flew from December 22, 1966 until July 17, 1970, and logged the highest and fastest records in the lifting body program.

The wingless, lifting body aircraft sitting on Rogers Dry Lake at what is now NASA's Dryden Flight Research Center, Edwards, California, from left to right are the X-24A, M2-F3 and the HL-10. The lifting body aircraft studied the feasibility of maneuvering and landing an aerodynamic craft designed for reentry from space. These lifting bodies were air launched by a B-52 mother ship, then flew powered by their own rocket engines before making an unpowered approach and landing. They helped validate the concept that a space shuttle could make accurate landings without power. The X-24A flew from April 17, 1969 to June 4, 1971. The M2-F3 flew from June 2, 1970 until December 20, 1972. The HL-10 flew from December 22, 1966 until July 17, 1970 and logged the highest and fastest records in the lifting body program.

The wingless, lifting body aircraft sitting on Rogers Dry Lake at what is now NASA's Dryden Flight Research Center, Edwards, California, from left to right are the X-24A, M2-F3 and the HL-10. The lifting body aircraft studied the feasibility of maneuvering and landing an aerodynamic craft designed for reentry from space. These lifting bodies were air launched by a B-52 mother ship, then flew powered by their own rocket engines before making an unpowered approach and landing. They helped validate the concept that a space shuttle could make accurate landings without power. The X-24A flew from April 17, 1969 to June 4, 1971. The M2-F3 flew from June 2, 1970 until December 20, 1972. The HL-10 flew from December 22, 1966 until July 17, 1970 and logged the highest and fastest records in the lifting body program.

CAPE CANAVERAL, Fla. – On Launch Pad 17-B at Cape Canaveral Air Force Station in Florida, workers complete the mating of the two fairing segments around NASA's Kepler spacecraft for encapsulation. The fairing is a molded structure that fits flush with the outside surface of the rocket and forms an aerodynamically smooth nose cone, protecting the spacecraft during launch and ascent. The liftoff of Kepler aboard the Delta II rocket is currently targeted for launch in a window extending 10:49 to 10:52 p.m. EST March 6 from Pad 17-B. Kepler is designed to survey more than 100,000 stars in our galaxy to determine the number of sun-like stars that have Earth-size and larger planets, including those that lie in a star's "habitable zone," a region where liquid water, and perhaps life, could exist. If these Earth-size worlds do exist around stars like our sun, Kepler is expected to be the first to find them and the first to measure how common they are. Photo credit: NASA/Jack Pfaller

CAPE CANAVERAL, Fla. – On Launch Pad 17-B at Cape Canaveral Air Force Station in Florida, workers watch closely as the second half of the fairing moves toward NASA's Kepler spacecraft (left) to complete encapsulation. The fairing is a molded structure that fits flush with the outside surface of the rocket and forms an aerodynamically smooth nose cone, protecting the spacecraft during launch and ascent. The liftoff of Kepler aboard the Delta II rocket is currently targeted for launch in a window extending 10:49 to 10:52 p.m. EST March 6 from Pad 17-B. Kepler is designed to survey more than 100,000 stars in our galaxy to determine the number of sun-like stars that have Earth-size and larger planets, including those that lie in a star's "habitable zone," a region where liquid water, and perhaps life, could exist. If these Earth-size worlds do exist around stars like our sun, Kepler is expected to be the first to find them and the first to measure how common they are. Photo credit: NASA/Jack Pfaller

CAPE CANAVERAL, Fla. – On Launch Pad 17-B at Cape Canaveral Air Force Station in Florida, workers watch closely as the second half of the fairing is moved into the mobile service tower for placement around NASA's Kepler spacecraft (left) to complete encapsulation. The fairing is a molded structure that fits flush with the outside surface of the rocket and forms an aerodynamically smooth nose cone, protecting the spacecraft during launch and ascent. The liftoff of Kepler aboard the Delta II rocket is currently targeted for launch in a window extending 10:49 to 10:52 p.m. EST March 6 from Pad 17-B. Kepler is designed to survey more than 100,000 stars in our galaxy to determine the number of sun-like stars that have Earth-size and larger planets, including those that lie in a star's "habitable zone," a region where liquid water, and perhaps life, could exist. If these Earth-size worlds do exist around stars like our sun, Kepler is expected to be the first to find them and the first to measure how common they are. Photo credit: NASA/Jack Pfaller

CAPE CANAVERAL, Fla. – On Launch Pad 17-B at Cape Canaveral Air Force Station in Florida, a worker examines the closure of the fairing segments around NASA's Kepler spacecraft. The fairing is a molded structure that fits flush with the outside surface of the rocket and forms an aerodynamically smooth nose cone, protecting the spacecraft during launch and ascent. The liftoff of Kepler aboard the Delta II rocket is currently targeted for launch in a window extending 10:49 to 10:52 p.m. EST March 6 from Pad 17-B. Kepler is designed to survey more than 100,000 stars in our galaxy to determine the number of sun-like stars that have Earth-size and larger planets, including those that lie in a star's "habitable zone," a region where liquid water, and perhaps life, could exist. If these Earth-size worlds do exist around stars like our sun, Kepler is expected to be the first to find them and the first to measure how common they are. Photo credit: NASA/Jack Pfaller

CAPE CANAVERAL, Fla. – On Launch Pad 17-B at Cape Canaveral Air Force Station in Florida, workers wait for the arrival of the two fairing components that will be installed around NASA's Kepler spacecraft, seen at left. The fairing is a molded structure that fits flush with the outside surface of the rocket and forms an aerodynamically smooth nose cone, protecting the spacecraft during launch and ascent. The liftoff of Kepler aboard the Delta II rocket is currently targeted for launch in a window extending 10:49 to 10:52 p.m. EST March 6 from Pad 17-B. Kepler is designed to survey more than 100,000 stars in our galaxy to determine the number of sun-like stars that have Earth-size and larger planets, including those that lie in a star's "habitable zone," a region where liquid water, and perhaps life, could exist. If these Earth-size worlds do exist around stars like our sun, Kepler is expected to be the first to find them and the first to measure how common they are. Photo credit: NASA/Jack Pfaller

CAPE CANAVERAL, Fla. – On Launch Pad 17-B at Cape Canaveral Air Force Station in Florida, the second half of the fairing moves closer to the first half around NASA's Kepler spacecraft for encapsulation. The fairing is a molded structure that fits flush with the outside surface of the rocket and forms an aerodynamically smooth nose cone, protecting the spacecraft during launch and ascent. The liftoff of Kepler aboard the Delta II rocket is currently targeted for launch in a window extending 10:49 to 10:52 p.m. EST March 6 from Pad 17-B. Kepler is designed to survey more than 100,000 stars in our galaxy to determine the number of sun-like stars that have Earth-size and larger planets, including those that lie in a star's "habitable zone," a region where liquid water, and perhaps life, could exist. If these Earth-size worlds do exist around stars like our sun, Kepler is expected to be the first to find them and the first to measure how common they are. Photo credit: NASA/Jack Pfaller

The second X-43A hypersonic research aircraft, attached to a modified Pegasus booster rocket and followed by a chase F-18, was taken to launch altitude by NASA's B-52B launch aircraft from the NASA Dryden Flight Research Center at Edwards Air Force Base, Calif., on March 27, 2004. About an hour later the Pegasus booster was released from the B-52 to accelerate the X-43A to its intended speed of Mach 7. In a combined research effort involving Dryden, Langley, and several industry partners, NASA demonstrated the value of its X-43A hypersonic research aircraft, as it became the first air-breathing, unpiloted, scramjet-powered plane to fly freely by itself. The March 27 flight, originating from NASA's Dryden Flight Research Center, began with the Agency's B-52B launch aircraft carrying the X-43A out to the test range over the Pacific Ocean off the California coast. The X-43A was boosted up to its test altitude of about 95,000 feet, where it separated from its modified Pegasus booster and flew freely under its own power. Two very significant aviation milestones occurred during this test flight: first, controlled accelerating flight at Mach 7 under scramjet power, and second, the successful stage separation at high dynamic pressure of two non-axisymmetric vehicles. To top it all off, the flight resulted in the setting of a new aeronautical speed record. The X-43A reached a speed of over Mach 7, or about 5,000 miles per hour faster than any known aircraft powered by an air-breathing engine has ever flown.

The M2-F2 Lifting Body is seen here on the ramp at the NASA Dryden Flight Research Center. The success of Dryden's M2-F1 program led to NASA's development and construction of two heavyweight lifting bodies based on studies at NASA's Ames and Langley research centers -- the M2-F2 and the HL-10, both built by the Northrop Corporation. The "M" refers to "manned" and "F" refers to "flight" version. "HL" comes from "horizontal landing" and 10 is for the tenth lifting body model to be investigated by Langley. The first flight of the M2-F2 -- which looked much like the "F1" -- was on July 12, 1966. Milt Thompson was the pilot. By then, the same B-52 used to air launch the famed X-15 rocket research aircraft was modified to also carry the lifting bodies. Thompson was dropped from the B-52's wing pylon mount at an altitude of 45,000 feet on that maiden glide flight. The M2-F2 weighed 4,620 pounds, was 22 feet long, and had a width of about 10 feet. On May 10, 1967, during the sixteenth glide flight leading up to powered flight, a landing accident severely damaged the vehicle and seriously injured the NASA pilot, Bruce Peterson. NASA pilots and researchers realized the M2-F2 had lateral control problems, even though it had a stability augmentation control system. When the M2-F2 was rebuilt at Dryden and redesignated the M2-F3, it was modified with an additional third vertical fin -- centered between the tip fins -- to improve control characteristics. The M2-F2/F3 was the first of the heavy-weight, entry-configuration lifting bodies. Its successful development as a research test vehicle answered many of the generic questions about these vehicles. NASA donated the M2-F3 vehicle to the Smithsonian Institute in December 1973. It is currently hanging in the Air and Space Museum along with the X-15 aircraft number 1, which was its hangar partner at Dryden from 1965 to 1969.

This photo shows the left side cockpit instrumentation panel of the M2-F2 Lifting Body. The success of Dryden's M2-F1 program led to NASA's development and construction of two heavyweight lifting bodies based on studies at NASA's Ames and Langley research centers -- the M2-F2 and the HL-10, both built by the Northrop Corporation. The "M" refers to "manned" and "F" refers to "flight" version. "HL" comes from "horizontal landing" and 10 is for the tenth lifting body model to be investigated by Langley. The first flight of the M2-F2 -- which looked much like the "F1" -- was on July 12, 1966. Milt Thompson was the pilot. By then, the same B-52 used to air launch the famed X-15 rocket research aircraft was modified to also carry the lifting bodies. Thompson was dropped from the B-52's wing pylon mount at an altitude of 45,000 feet on that maiden glide flight. The M2-F2 weighed 4,620 pounds, was 22 feet long, and had a width of about 10 feet. On May 10, 1967, during the sixteenth glide flight leading up to powered flight, a landing accident severely damaged the vehicle and seriously injured the NASA pilot, Bruce Peterson. NASA pilots and researchers realized the M2-F2 had lateral control problems, even though it had a stability augmentation control system. When the M2-F2 was rebuilt at Dryden and redesignated the M2-F3, it was modified with an additional third vertical fin -- centered between the tip fins -- to improve control characteristics. The M2-F2/F3 was the first of the heavy-weight, entry-configuration lifting bodies. Its successful development as a research test vehicle answered many of the generic questions about these vehicles. NASA donated the M2-F3 vehicle to the Smithsonian Institute in December 1973. It is currently hanging in the Air and Space Museum along with the X-15 aircraft number 1, which was its hangar partner at Dryden from 1965 to 1969.

This photo shows the right side cockpit instrumentation panel of the M2-F2 Lifting Body. The success of Dryden's M2-F1 program led to NASA's development and construction of two heavyweight lifting bodies based on studies at NASA's Ames and Langley research centers -- the M2-F2 and the HL-10, both built by the Northrop Corporation. The "M" refers to "manned" and "F" refers to "flight" version. "HL" comes from "horizontal landing" and 10 is for the tenth lifting body model to be investigated by Langley. The first flight of the M2-F2 -- which looked much like the "F1" -- was on July 12, 1966. Milt Thompson was the pilot. By then, the same B-52 used to air launch the famed X-15 rocket research aircraft was modified to also carry the lifting bodies. Thompson was dropped from the B-52's wing pylon mount at an altitude of 45,000 feet on that maiden glide flight. The M2-F2 weighed 4,620 pounds, was 22 feet long, and had a width of about 10 feet. On May 10, 1967, during the sixteenth glide flight leading up to powered flight, a landing accident severely damaged the vehicle and seriously injured the NASA pilot, Bruce Peterson. NASA pilots and researchers realized the M2-F2 had lateral control problems, even though it had a stability augmentation control system. When the M2-F2 was rebuilt at Dryden and redesignated the M2-F3, it was modified with an additional third vertical fin -- centered between the tip fins -- to improve control characteristics. The M2-F2/F3 was the first of the heavy-weight, entry-configuration lifting bodies. Its successful development as a research test vehicle answered many of the generic questions about these vehicles. NASA donated the M2-F3 vehicle to the Smithsonian Institute in December 1973. It is currently hanging in the Air and Space Museum along with the X-15 aircraft number 1, which was its hangar partner at Dryden from 1965 to 1969.

CAPE CANAVERAL, Fla. – A group of trees and bushes provides a frame for the launch of the United Launch Alliance Delta II Heavy rocket carrying NASA’s twin Gravity Recovery and Interior Laboratory (GRAIL) mission off Space Launch Complex 17B on Cape Canaveral Air Force Station in Florida. The spacecraft launched at 9:08:52 a.m. EDT Sept. 10. GRAIL-A will separate from the second stage of the rocket at about one hour, 21 minutes after liftoff, followed by GRAIL-B at 90 minutes after launch. The spacecraft are embarking on a three-month journey to reach the moon. GRAIL will fly twin spacecraft in tandem around the moon to precisely measure and map variations in the moon's gravitational field. The mission will provide the most accurate global gravity field to date for any planet, including Earth. This detailed information will reveal differences in the density of the moon's crust and mantle and will help answer fundamental questions about the moon's internal structure, thermal evolution, and history of collisions with asteroids. The aim is to map the moon's gravity field so completely that future moon vehicles can safely navigate anywhere on the moon’s surface. For more information, visit http://www.nasa.gov/grail. Photo credit: NASA/George Roberts

CAPE CANAVERAL, Fla. – Over a group of trees and bushes, the United Launch Alliance Delta II Heavy rocket carrying NASA’s twin Gravity Recovery and Interior Laboratory (GRAIL) mission launches off Space Launch Complex 17B on Cape Canaveral Air Force Station in Florida. The spacecraft launched at 9:08:52 a.m. EDT Sept. 10. GRAIL-A will separate from the second stage of the rocket at about one hour, 21 minutes after liftoff, followed by GRAIL-B at 90 minutes after launch. The spacecraft are embarking on a three-month journey to reach the moon. GRAIL will fly twin spacecraft in tandem around the moon to precisely measure and map variations in the moon's gravitational field. The mission will provide the most accurate global gravity field to date for any planet, including Earth. This detailed information will reveal differences in the density of the moon's crust and mantle and will help answer fundamental questions about the moon's internal structure, thermal evolution, and history of collisions with asteroids. The aim is to map the moon's gravity field so completely that future moon vehicles can safely navigate anywhere on the moon’s surface. For more information, visit http://www.nasa.gov/grail. Photo credit: NASA/George Roberts

CAPE CANAVERAL, Fla. – Over a group of trees and bushes, the United Launch Alliance Delta II Heavy rocket carrying NASA’s twin Gravity Recovery and Interior Laboratory (GRAIL) mission launches off Space Launch Complex 17B on Cape Canaveral Air Force Station in Florida. At left is the pad’s mobile service tower. The spacecraft launched at 9:08:52 a.m. EDT Sept. 10. GRAIL-A will separate from the second stage of the rocket at about one hour, 21 minutes after liftoff, followed by GRAIL-B at 90 minutes after launch. The spacecraft are embarking on a three-month journey to reach the moon. GRAIL will fly twin spacecraft in tandem around the moon to precisely measure and map variations in the moon's gravitational field. The mission will provide the most accurate global gravity field to date for any planet, including Earth. This detailed information will reveal differences in the density of the moon's crust and mantle and will help answer fundamental questions about the moon's internal structure, thermal evolution, and history of collisions with asteroids. The aim is to map the moon's gravity field so completely that future moon vehicles can safely navigate anywhere on the moon’s surface. For more information, visit http://www.nasa.gov/grail. Photo credit: NASA/Kenny Allen

CAPE CANAVERAL, Fla. – Rising from fire and smoke, NASA’s twin Gravity Recovery and Interior Laboratory (GRAIL) mission launches atop a United Launch Alliance Delta II Heavy rocket. Leaving from Space Launch Complex 17B on Cape Canaveral Air Force Station in Florida, the spacecraft launched at 9:08:52 a.m. EDT Sept.10. GRAIL-A will separate from the second stage of the rocket at about one hour, 21 minutes after liftoff, followed by GRAIL-B at 90 minutes after launch. The spacecraft are embarking on a three-month journey to reach the moon. GRAIL will fly twin spacecraft in tandem around the moon to precisely measure and map variations in the moon's gravitational field. The mission will provide the most accurate global gravity field to date for any planet, including Earth. This detailed information will reveal differences in the density of the moon's crust and mantle and will help answer fundamental questions about the moon's internal structure, thermal evolution, and history of collisions with asteroids. The aim is to map the moon's gravity field so completely that future moon vehicles can safely navigate anywhere on the moon’s surface. For more information, visit http://www.nasa.gov/grail. Photo credit: NASA/Darrell McCall

CAPE CANAVERAL, Fla. – Over a group of trees and bushes, the United Launch Alliance Delta II Heavy rocket carrying NASA’s twin Gravity Recovery and Interior Laboratory (GRAIL) mission launches off Space Launch Complex 17B on Cape Canaveral Air Force Station in Florida. At left is the pad’s mobile service tower. The spacecraft launched at 9:08:52 a.m. EDT Sept. 10. GRAIL-A will separate from the second stage of the rocket at about one hour, 21 minutes after liftoff, followed by GRAIL-B at 90 minutes after launch. The spacecraft are embarking on a three-month journey to reach the moon. GRAIL will fly twin spacecraft in tandem around the moon to precisely measure and map variations in the moon's gravitational field. The mission will provide the most accurate global gravity field to date for any planet, including Earth. This detailed information will reveal differences in the density of the moon's crust and mantle and will help answer fundamental questions about the moon's internal structure, thermal evolution, and history of collisions with asteroids. The aim is to map the moon's gravity field so completely that future moon vehicles can safely navigate anywhere on the moon’s surface. For more information, visit http://www.nasa.gov/grail. Photo credit: NASA/Kenny Allen

CAPE CANAVERAL, Fla. – Rising from fire and smoke after liftoff, NASA’s twin Gravity Recovery and Interior Laboratory (GRAIL) mission launches atop a United Launch Alliance Delta II Heavy rocket leaving from Space Launch Complex 17B on Cape Canaveral Air Force Station in Florida. At left is the pad’s mobile service tower. The spacecraft launched at 9:08:52 a.m. EDT Sept. 10. GRAIL-A will separate from the second stage of the rocket at about one hour, 21 minutes after liftoff, followed by GRAIL-B at 90 minutes after launch. The spacecraft are embarking on a three-month journey to reach the moon. GRAIL will fly twin spacecraft in tandem around the moon to precisely measure and map variations in the moon's gravitational field. The mission will provide the most accurate global gravity field to date for any planet, including Earth. This detailed information will reveal differences in the density of the moon's crust and mantle and will help answer fundamental questions about the moon's internal structure, thermal evolution, and history of collisions with asteroids. The aim is to map the moon's gravity field so completely that future moon vehicles can safely navigate anywhere on the moon’s surface. For more information, visit http://www.nasa.gov/grail. Photo credit: NASA/Kenny Allen

CAPE CANAVERAL, Fla. – Plumes of smoke surround of the United Launch Alliance Delta II Heavy rocket carrying NASA’s twin Gravity Recovery and Interior Laboratory (GRAIL) mission off Space Launch Complex 17B on Cape Canaveral Air Force Station In Florida. The spacecraft launched at 9:08:52 a.m. EDT Sept. 10. GRAIL-A will separate from the second stage of the rocket at about one hour, 21 minutes after liftoff, followed by GRAIL-B at 90 minutes after launch. The spacecraft are embarking on a three-month journey to reach the moon. GRAIL will fly twin spacecraft in tandem around the moon to precisely measure and map variations in the moon's gravitational field. The mission will provide the most accurate global gravity field to date for any planet, including Earth. This detailed information will reveal differences in the density of the moon's crust and mantle and will help answer fundamental questions about the moon's internal structure, thermal evolution, and history of collisions with asteroids. The aim is to map the moon's gravity field so completely that future moon vehicles can safely navigate anywhere on the moon’s surface. For more information, visit http://www.nasa.gov/grail. Photo credit: NASA/Sandra Joseph and Don Kight

CAPE CANAVERAL, Fla. – At ignition, flames and smoke from the engines begin liftoff of the United Launch Alliance Delta II Heavy rocket carrying NASA’s twin Gravity Recovery and Interior Laboratory (GRAIL) mission off Space Launch Complex 17B on Cape Canaveral Air Force Station in Florida. At right is the pad’s mobile service tower. The spacecraft launched at 9:08:52 a.m. EDT Sept. 10. GRAIL-A will separate from the second stage of the rocket at about one hour, 21 minutes after liftoff, followed by GRAIL-B at 90 minutes after launch. The spacecraft are embarking on a three-month journey to reach the moon. GRAIL will fly twin spacecraft in tandem around the moon to precisely measure and map variations in the moon's gravitational field. The mission will provide the most accurate global gravity field to date for any planet, including Earth. This detailed information will reveal differences in the density of the moon's crust and mantle and will help answer fundamental questions about the moon's internal structure, thermal evolution, and history of collisions with asteroids. The aim is to map the moon's gravity field so completely that future moon vehicles can safely navigate anywhere on the moon’s surface. For more information, visit http://www.nasa.gov/grail. Photo credit: NASA/Tom Farrar and Tony Gray

CAPE CANAVERAL, Fla. – Flames and smoke from the engines surround the United Launch Alliance Delta II rocket at liftoff carrying NASA’s twin Gravity Recovery and Interior Laboratory (GRAIL) mission off Space Launch Complex 17B on Cape Canaveral Air Force Station in Florida. At right is the pad’s mobile service tower. The spacecraft launched at 9:08:52 a.m. EDT Sept. 10. GRAIL-A will separate from the second stage of the rocket at about one hour, 21 minutes after liftoff, followed by GRAIL-B at 90 minutes after launch. The spacecraft are embarking on a three-month journey to reach the moon. GRAIL will fly twin spacecraft in tandem around the moon to precisely measure and map variations in the moon's gravitational field. The mission will provide the most accurate global gravity field to date for any planet, including Earth. This detailed information will reveal differences in the density of the moon's crust and mantle and will help answer fundamental questions about the moon's internal structure, thermal evolution, and history of collisions with asteroids. The aim is to map the moon's gravity field so completely that future moon vehicles can safely navigate anywhere on the moon’s surface. For more information, visit http://www.nasa.gov/grail. Photo credit: NASA/Tom Farrar and Tony Gray

CAPE CANAVERAL, Fla. – At ignition, flames and smoke from the engines begin liftoff of the United Launch Alliance Delta II Heavy rocket carrying NASA’s twin Gravity Recovery and Interior Laboratory (GRAIL) mission off Space Launch Complex 17B on Cape Canaveral Air Force Station in Florida. The spacecraft launched at 9:08:52 a.m. EDT Sept. 10. GRAIL-A will separate from the second stage of the rocket at about one hour, 21 minutes after liftoff, followed by GRAIL-B at 90 minutes after launch. The spacecraft are embarking on a three-month journey to reach the moon. GRAIL will fly twin spacecraft in tandem around the moon to precisely measure and map variations in the moon's gravitational field. The mission will provide the most accurate global gravity field to date for any planet, including Earth. This detailed information will reveal differences in the density of the moon's crust and mantle and will help answer fundamental questions about the moon's internal structure, thermal evolution, and history of collisions with asteroids. The aim is to map the moon's gravity field so completely that future moon vehicles can safely navigate anywhere on the moon’s surface. For more information, visit http://www.nasa.gov/grail. Photo credit: NASA/ Tony Gray and Tim Powers

CAPE CANAVERAL, Fla. – Plumes of smoke surround of the United Launch Alliance Delta II Heavy rocket carrying NASA’s twin Gravity Recovery and Interior Laboratory (GRAIL) mission off Space Launch Complex 17B on Cape Canaveral Air Force Station in Florida. At right is the pad’s mobile service tower. The spacecraft launched at 9:08:52 a.m. EDT Sept. 10. GRAIL-A will separate from the second stage of the rocket at about one hour, 21 minutes after liftoff, followed by GRAIL-B at 90 minutes after launch. The spacecraft are embarking on a three-month journey to reach the moon. GRAIL will fly twin spacecraft in tandem around the moon to precisely measure and map variations in the moon's gravitational field. The mission will provide the most accurate global gravity field to date for any planet, including Earth. This detailed information will reveal differences in the density of the moon's crust and mantle and will help answer fundamental questions about the moon's internal structure, thermal evolution, and history of collisions with asteroids. The aim is to map the moon's gravity field so completely that future moon vehicles can safely navigate anywhere on the moon’s surface. For more information, visit http://www.nasa.gov/grail. Photo credit: NASA/Tom Farrar and Tony Gray

CAPE CANAVERAL, Fla. – Engine ignition begins liftoff of the United Launch Alliance Delta II Heavy rocket carrying NASA’s twin Gravity Recovery and Interior Laboratory (GRAIL) mission off Space Launch Complex 17B on Cape Canaveral Air Force Station in Florida. At right is the pad’s mobile service tower. The spacecraft launched at 9:08:52 a.m. EDT Sept. 10. GRAIL-A will separate from the second stage of the rocket at about one hour, 21 minutes after liftoff, followed by GRAIL-B at 90 minutes after launch. The spacecraft are embarking on a three-month journey to reach the moon. GRAIL will fly twin spacecraft in tandem around the moon to precisely measure and map variations in the moon's gravitational field. The mission will provide the most accurate global gravity field to date for any planet, including Earth. This detailed information will reveal differences in the density of the moon's crust and mantle and will help answer fundamental questions about the moon's internal structure, thermal evolution, and history of collisions with asteroids. The aim is to map the moon's gravity field so completely that future moon vehicles can safely navigate anywhere on the moon’s surface. For more information, visit http://www.nasa.gov/grail. Photo credit: NASA/Tom Farrar and Tony Gray

CAPE CANAVERAL, Fla. – At ignition, flames and smoke from the engines begin liftoff of the United Launch Alliance Delta II Heavy rocket carrying NASA’s twin Gravity Recovery and Interior Laboratory (GRAIL) mission off Space Launch Complex 17B on Cape Canaveral Air Force Station in Florida. The spacecraft launched at 9:08:52 a.m. EDT Sept. 10. GRAIL-A will separate from the second stage of the rocket at about one hour, 21 minutes after liftoff, followed by GRAIL-B at 90 minutes after launch. The spacecraft are embarking on a three-month journey to reach the moon. GRAIL will fly twin spacecraft in tandem around the moon to precisely measure and map variations in the moon's gravitational field. The mission will provide the most accurate global gravity field to date for any planet, including Earth. This detailed information will reveal differences in the density of the moon's crust and mantle and will help answer fundamental questions about the moon's internal structure, thermal evolution, and history of collisions with asteroids. The aim is to map the moon's gravity field so completely that future moon vehicles can safely navigate anywhere on the moon’s surface. For more information, visit http://www.nasa.gov/grail. Photo credit: NASA/ Tony Gray and Tim Powers

CAPE CANAVERAL, Fla. – At ignition, flames and smoke from the engines begin liftoff of the United Launch Alliance Delta II Heavy rocket carrying NASA’s twin Gravity Recovery and Interior Laboratory (GRAIL) mission off Space Launch Complex 17B on Cape Canaveral Air Force Station in Florida. The spacecraft launched at 9:08:52 a.m. EDT Sept. 10. GRAIL-A will separate from the second stage of the rocket at about one hour, 21 minutes after liftoff, followed by GRAIL-B at 90 minutes after launch. The spacecraft are embarking on a three-month journey to reach the moon. GRAIL will fly twin spacecraft in tandem around the moon to precisely measure and map variations in the moon's gravitational field. The mission will provide the most accurate global gravity field to date for any planet, including Earth. This detailed information will reveal differences in the density of the moon's crust and mantle and will help answer fundamental questions about the moon's internal structure, thermal evolution, and history of collisions with asteroids. The aim is to map the moon's gravity field so completely that future moon vehicles can safely navigate anywhere on the moon’s surface. For more information, visit http://www.nasa.gov/grail. Photo credit: NASA/Sandra Joseph and Don Kight

CAPE CANAVERAL, Fla. – Flames and smoke from the engines surround the United Launch Alliance Delta II rocket at liftoff carrying NASA’s twin Gravity Recovery and Interior Laboratory (GRAIL) mission off Space Launch Complex 17B on Cape Canaveral Air Force Station in Florida. The spacecraft launched at 9:08:52 a.m. EDT Sept. 10. GRAIL-A will separate from the second stage of the rocket at about one hour, 21 minutes after liftoff, followed by GRAIL-B at 90 minutes after launch. The spacecraft are embarking on a three-month journey to reach the moon. GRAIL will fly twin spacecraft in tandem around the moon to precisely measure and map variations in the moon's gravitational field. The mission will provide the most accurate global gravity field to date for any planet, including Earth. This detailed information will reveal differences in the density of the moon's crust and mantle and will help answer fundamental questions about the moon's internal structure, thermal evolution, and history of collisions with asteroids. The aim is to map the moon's gravity field so completely that future moon vehicles can safely navigate anywhere on the moon’s surface. For more information, visit http://www.nasa.gov/grail. Photo credit: NASA/Sandra Joseph and Don Kight

CAPE CANAVERAL, Fla. – Rising from fire and smoke after liftoff, NASA’s twin Gravity Recovery and Interior Laboratory (GRAIL) mission launches atop a United Launch Alliance Delta II Heavy rocket leaving from Space Launch Complex 17B on Cape Canaveral Air Force Station in Florida. Liftoff was at 9:08:52 a.m. EDT Sept. 10. GRAIL-A will separate from the second stage of the rocket at about one hour, 21 minutes after liftoff, followed by GRAIL-B at 90 minutes after launch. The spacecraft are embarking on a three-month journey to reach the moon. GRAIL will fly twin spacecraft in tandem around the moon to precisely measure and map variations in the moon's gravitational field. The mission will provide the most accurate global gravity field to date for any planet, including Earth. This detailed information will reveal differences in the density of the moon's crust and mantle and will help answer fundamental questions about the moon's internal structure, thermal evolution, and history of collisions with asteroids. The aim is to map the moon's gravity field so completely that future moon vehicles can safely navigate anywhere on the moon’s surface. For more information, visit http://www.nasa.gov/grail. Photo credit: NASA/ Tony Gray and Tim Powers

CAPE CANAVERAL, Fla. – The United Launch Alliance Delta II Heavy rocket propels NASA’s twin Gravity Recovery and Interior Laboratory (GRAIL) mission into the clouds over Space Launch Complex 17B on Cape Canaveral Air Force Station in Florida. The spacecraft launched at 9:08:52 a.m. EDT Sept. 10. GRAIL-A will separate from the second stage of the rocket at about one hour, 21 minutes after liftoff, followed by GRAIL-B at 90 minutes after launch. The spacecraft are embarking on a three-month journey to reach the moon. GRAIL will fly twin spacecraft in tandem around the moon to precisely measure and map variations in the moon's gravitational field. The mission will provide the most accurate global gravity field to date for any planet, including Earth. This detailed information will reveal differences in the density of the moon's crust and mantle and will help answer fundamental questions about the moon's internal structure, thermal evolution, and history of collisions with asteroids. The aim is to map the moon's gravity field so completely that future moon vehicles can safely navigate anywhere on the moon’s surface. For more information, visit http://www.nasa.gov/grail. Photo credit: NASA/Kenny Allen

CAPE CANAVERAL, Fla. – Plumes of smoke trail the United Launch Alliance Delta II Heavy rocket launching NASA’s Gravity Recovery and Interior Laboratory (GRAIL) mission into space as media representatives at Press Site 1 near Space Launch Complex 17B on Cape Canaveral Air Force Station in Florida photograph it. Liftoff was at 9:08:52 a.m. EDT Sept.10. GRAIL-A will separate from the second stage of the rocket at about one hour, 21 minutes after liftoff, followed by GRAIL-B at 90 minutes after launch. The spacecraft are embarking on a three-month journey to reach the moon. GRAIL will fly twin spacecraft in tandem around the moon to precisely measure and map variations in the moon's gravitational field. The mission will provide the most accurate global gravity field to date for any planet, including Earth. This detailed information will reveal differences in the density of the moon's crust and mantle and will help answer fundamental questions about the moon's internal structure, thermal evolution, and history of collisions with asteroids. The aim is to map the moon's gravity field so completely that future moon vehicles can safely navigate anywhere on the moon’s surface. For more information, visit http://www.nasa.gov/grail. Photo credit: NASA/ Kim Shiflett

CAPE CANAVERAL, Fla. – At ignition, flames from the engines begin liftoff of the United Launch Alliance Delta II Heavy rocket carrying NASA’s twin Gravity Recovery and Interior Laboratory (GRAIL) mission off Space Launch Complex 17B on Cape Canaveral Air Force Station. The spacecraft launched at 9:08:52 a.m. EDT Sept. 10. GRAIL-A will separate from the second stage of the rocket at about one hour, 21 minutes after liftoff, followed by GRAIL-B at 90 minutes after launch. The spacecraft are embarking on a three-month journey to reach the moon. GRAIL will fly twin spacecraft in tandem around the moon to precisely measure and map variations in the moon's gravitational field. The mission will provide the most accurate global gravity field to date for any planet, including Earth. This detailed information will reveal differences in the density of the moon's crust and mantle and will help answer fundamental questions about the moon's internal structure, thermal evolution, and history of collisions with asteroids. The aim is to map the moon's gravity field so completely that future moon vehicles can safely navigate anywhere on the moon’s surface. For more information, visit http://www.nasa.gov/grail. Photo credit: NASA/Sandra Joseph and Don Kight

CAPE CANAVERAL, Fla. – Backdropped by a beautiful blue sky, at ignition, flames and smoke from the engines begin liftoff of the United Launch Alliance Delta II Heavy rocket carrying NASA’s twin Gravity Recovery and Interior Laboratory (GRAIL) mission off Space Launch Complex 17B on Cape Canaveral Air Force Station in Florida. At right is the pad’s mobile service tower. The spacecraft launched at 9:08:52 a.m. EDT Sept. 10. GRAIL-A will separate from the second stage of the rocket at about one hour, 21 minutes after liftoff, followed by GRAIL-B at 90 minutes after launch. The spacecraft are embarking on a three-month journey to reach the moon. GRAIL will fly twin spacecraft in tandem around the moon to precisely measure and map variations in the moon's gravitational field. The mission will provide the most accurate global gravity field to date for any planet, including Earth. This detailed information will reveal differences in the density of the moon's crust and mantle and will help answer fundamental questions about the moon's internal structure, thermal evolution, and history of collisions with asteroids. The aim is to map the moon's gravity field so completely that future moon vehicles can safely navigate anywhere on the moon’s surface. For more information, visit http://www.nasa.gov/grail. Photo credit: NASA/Sandra Joseph and Don Kight

CAPE CANAVERAL, Fla. – Under a blue sky, engine ignition begins liftoff of the United Launch Alliance Delta II Heavy rocket carrying NASA’s twin Gravity Recovery and Interior Laboratory (GRAIL) mission off Space Launch Complex 17B on Cape Canaveral Air Force Station in Florida. The spacecraft launched at 9:08:52 a.m. EDT Sept. 10. GRAIL-A will separate from the second stage of the rocket at about one hour, 21 minutes after liftoff, followed by GRAIL-B at 90 minutes after launch. The spacecraft are embarking on a three-month journey to reach the moon. GRAIL will fly twin spacecraft in tandem around the moon to precisely measure and map variations in the moon's gravitational field. The mission will provide the most accurate global gravity field to date for any planet, including Earth. This detailed information will reveal differences in the density of the moon's crust and mantle and will help answer fundamental questions about the moon's internal structure, thermal evolution, and history of collisions with asteroids. The aim is to map the moon's gravity field so completely that future moon vehicles can safely navigate anywhere on the moon’s surface. For more information, visit http://www.nasa.gov/grail. Photo credit: NASA/Sandra Joseph and Don Kight

CAPE CANAVERAL, Fla. – Overlooking the Central Florida coast, engine ignition begins liftoff of the United Launch Alliance Delta II Heavy rocket carrying NASA’s twin Gravity Recovery and Interior Laboratory (GRAIL) mission off Space Launch Complex 17B on Cape Canaveral Air Force Station. The spacecraft launched at 9:08:52 a.m. EDT Sept. 10. GRAIL-A will separate from the second stage of the rocket at about one hour, 21 minutes after liftoff, followed by GRAIL-B at 90 minutes after launch. The spacecraft are embarking on a three-month journey to reach the moon. GRAIL will fly twin spacecraft in tandem around the moon to precisely measure and map variations in the moon's gravitational field. The mission will provide the most accurate global gravity field to date for any planet, including Earth. This detailed information will reveal differences in the density of the moon's crust and mantle and will help answer fundamental questions about the moon's internal structure, thermal evolution, and history of collisions with asteroids. The aim is to map the moon's gravity field so completely that future moon vehicles can safely navigate anywhere on the moon’s surface. For more information, visit http://www.nasa.gov/grail. Photo credit: NASA/Sandra Joseph and Don Kight

CAPE CANAVERAL, Fla. – Backdropped by a beautiful blue sky, flames and smoke from the engines surround the United Launch Alliance Delta II rocket at liftoff carrying NASA’s twin Gravity Recovery and Interior Laboratory (GRAIL) mission off Space Launch Complex 17B on Cape Canaveral Air Force Station in Florida. The spacecraft launched at 9:08:52 a.m. EDT Sept. 10. GRAIL-A will separate from the second stage of the rocket at about one hour, 21 minutes after liftoff, followed by GRAIL-B at 90 minutes after launch. The spacecraft are embarking on a three-month journey to reach the moon. GRAIL will fly twin spacecraft in tandem around the moon to precisely measure and map variations in the moon's gravitational field. The mission will provide the most accurate global gravity field to date for any planet, including Earth. This detailed information will reveal differences in the density of the moon's crust and mantle and will help answer fundamental questions about the moon's internal structure, thermal evolution, and history of collisions with asteroids. The aim is to map the moon's gravity field so completely that future moon vehicles can safely navigate anywhere on the moon’s surface. For more information, visit http://www.nasa.gov/grail. Photo credit: NASA/Sandra Joseph and Don Kight

CAPE CANAVERAL, Fla. – Overlooking the Central Florida coast, engine ignition begins liftoff of the United Launch Alliance Delta II Heavy rocket carrying NASA’s twin Gravity Recovery and Interior Laboratory (GRAIL) mission off Space Launch Complex 17B on Cape Canaveral Air Force Station. The spacecraft launched at 9:08:52 a.m. EDT Sept. 10. GRAIL-A will separate from the second stage of the rocket at about one hour, 21 minutes after liftoff, followed by GRAIL-B at 90 minutes after launch. The spacecraft are embarking on a three-month journey to reach the moon. GRAIL will fly twin spacecraft in tandem around the moon to precisely measure and map variations in the moon's gravitational field. The mission will provide the most accurate global gravity field to date for any planet, including Earth. This detailed information will reveal differences in the density of the moon's crust and mantle and will help answer fundamental questions about the moon's internal structure, thermal evolution, and history of collisions with asteroids. The aim is to map the moon's gravity field so completely that future moon vehicles can safely navigate anywhere on the moon’s surface. For more information, visit http://www.nasa.gov/grail. Photo credit: NASA/Sandra Joseph and Don Kight

CAPE CANAVERAL, Fla. – At ignition, flames and smoke from the engines begin liftoff of the United Launch Alliance Delta II Heavy rocket carrying NASA’s twin Gravity Recovery and Interior Laboratory (GRAIL) mission off Space Launch Complex 17B on Cape Canaveral Air Force Station in Florida. At left is the pad’s mobile service tower. The spacecraft launched at 9:08:52 a.m. EDT Sept. 10. GRAIL-A will separate from the second stage of the rocket at about one hour, 21 minutes after liftoff, followed by GRAIL-B at 90 minutes after launch. The spacecraft are embarking on a three-month journey to reach the moon. GRAIL will fly twin spacecraft in tandem around the moon to precisely measure and map variations in the moon's gravitational field. The mission will provide the most accurate global gravity field to date for any planet, including Earth. This detailed information will reveal differences in the density of the moon's crust and mantle and will help answer fundamental questions about the moon's internal structure, thermal evolution, and history of collisions with asteroids. The aim is to map the moon's gravity field so completely that future moon vehicles can safely navigate anywhere on the moon’s surface. For more information, visit http://www.nasa.gov/grail. Photo credit: NASA/Kenny Allen

CAPE CANAVERAL, Fla. – Sun reflects off the United Launch Alliance Delta II Heavy rocket launching NASA’s Gravity Recovery and Interior Laboratory (GRAIL) mission into space as media representatives at Press Site 1 near Space Launch Complex 17B on Cape Canaveral Air Force Station in Florida capture the moment. Liftoff was at 9:08:52 a.m. EDT Sept.10. GRAIL-A will separate from the second stage of the rocket at about one hour, 21 minutes after liftoff, followed by GRAIL-B at 90 minutes after launch. The spacecraft are embarking on a three-month journey to reach the moon. GRAIL will fly twin spacecraft in tandem around the moon to precisely measure and map variations in the moon's gravitational field. The mission will provide the most accurate global gravity field to date for any planet, including Earth. This detailed information will reveal differences in the density of the moon's crust and mantle and will help answer fundamental questions about the moon's internal structure, thermal evolution, and history of collisions with asteroids. The aim is to map the moon's gravity field so completely that future moon vehicles can safely navigate anywhere on the moon’s surface. For more information, visit http://www.nasa.gov/grail. Photo credit: NASA/ Kim Shiflett

CAPE CANAVERAL, Fla. – At ignition, flames and smoke from the engines begin liftoff of the United Launch Alliance Delta II Heavy rocket carrying NASA’s twin Gravity Recovery and Interior Laboratory (GRAIL) mission off Space Launch Complex 17B on Cape Canaveral Air Force Station in Florida. The spacecraft launched at 9:08:52 a.m. EDT Sept. 10. GRAIL-A will separate from the second stage of the rocket at about one hour, 21 minutes after liftoff, followed by GRAIL-B at 90 minutes after launch. The spacecraft are embarking on a three-month journey to reach the moon. GRAIL will fly twin spacecraft in tandem around the moon to precisely measure and map variations in the moon's gravitational field. The mission will provide the most accurate global gravity field to date for any planet, including Earth. This detailed information will reveal differences in the density of the moon's crust and mantle and will help answer fundamental questions about the moon's internal structure, thermal evolution, and history of collisions with asteroids. The aim is to map the moon's gravity field so completely that future moon vehicles can safely navigate anywhere on the moon’s surface. For more information, visit http://www.nasa.gov/grail. Photo credit: NASA/Sandra Joseph and Don Kight

CAPE CANAVERAL, Fla. – Overlooking the Central Florida coast, engine ignition begins liftoff of the United Launch Alliance Delta II Heavy rocket carrying NASA’s twin Gravity Recovery and Interior Laboratory (GRAIL) mission off Space Launch Complex 17B on Cape Canaveral Air Force Station. The spacecraft launched at 9:08:52 a.m. EDT Sept. 10. GRAIL-A will separate from the second stage of the rocket at about one hour, 21 minutes after liftoff, followed by GRAIL-B at 90 minutes after launch. The spacecraft are embarking on a three-month journey to reach the moon. GRAIL will fly twin spacecraft in tandem around the moon to precisely measure and map variations in the moon's gravitational field. The mission will provide the most accurate global gravity field to date for any planet, including Earth. This detailed information will reveal differences in the density of the moon's crust and mantle and will help answer fundamental questions about the moon's internal structure, thermal evolution, and history of collisions with asteroids. The aim is to map the moon's gravity field so completely that future moon vehicles can safely navigate anywhere on the moon’s surface. For more information, visit http://www.nasa.gov/grail. Photo credit: NASA/Sandra Joseph and Don Kight

CAPE CANAVERAL, Fla. – At liftoff, plumes of smoke surround the United Launch Alliance Delta II Heavy rocket carrying NASA’s twin Gravity Recovery and Interior Laboratory (GRAIL) mission off Space Launch Complex 17B on Cape Canaveral Air Force Station in Florida. The spacecraft launched at 9:08:52 a.m. EDT Sept. 10. GRAIL-A will separate from the second stage of the rocket at about one hour, 21 minutes after liftoff, followed by GRAIL-B at 90 minutes after launch. The spacecraft are embarking on a three-month journey to reach the moon. GRAIL will fly twin spacecraft in tandem around the moon to precisely measure and map variations in the moon's gravitational field. The mission will provide the most accurate global gravity field to date for any planet, including Earth. This detailed information will reveal differences in the density of the moon's crust and mantle and will help answer fundamental questions about the moon's internal structure, thermal evolution, and history of collisions with asteroids. The aim is to map the moon's gravity field so completely that future moon vehicles can safely navigate anywhere on the moon’s surface. For more information, visit http://www.nasa.gov/grail. Photo credit: NASA/ Tony Gray and Tim Powers

CAPE CANAVERAL, Fla. – Backdropped by a beautiful blue sky, the United Launch Alliance Delta II Heavy rocket propels NASA’s twin Gravity Recovery and Interior Laboratory (GRAIL) mission off Space Launch Complex 17B on Cape Canaveral Air Force Station in Florida. The spacecraft launched at 9:08:52 a.m. EDT Sept. 10. GRAIL-A will separate from the second stage of the rocket at about one hour, 21 minutes after liftoff, followed by GRAIL-B at 90 minutes after launch. The spacecraft are embarking on a three-month journey to reach the moon. GRAIL will fly twin spacecraft in tandem around the moon to precisely measure and map variations in the moon's gravitational field. The mission will provide the most accurate global gravity field to date for any planet, including Earth. This detailed information will reveal differences in the density of the moon's crust and mantle and will help answer fundamental questions about the moon's internal structure, thermal evolution, and history of collisions with asteroids. The aim is to map the moon's gravity field so completely that future moon vehicles can safely navigate anywhere on the moon’s surface. For more information, visit http://www.nasa.gov/grail. Photo credit: NASA/George Roberts

CAPE CANAVERAL, Fla. – Engine ignition begins liftoff of the United Launch Alliance Delta II Heavy rocket carrying NASA’s twin Gravity Recovery and Interior Laboratory (GRAIL) mission off Space Launch Complex 17B on Cape Canaveral Air Force Station in Florida. At right is the pad’s mobile service tower. The spacecraft launched at 9:08:52 a.m. EDT Sept. 10. GRAIL-A will separate from the second stage of the rocket at about one hour, 21 minutes after liftoff, followed by GRAIL-B at 90 minutes after launch. The spacecraft are embarking on a three-month journey to reach the moon. GRAIL will fly twin spacecraft in tandem around the moon to precisely measure and map variations in the moon's gravitational field. The mission will provide the most accurate global gravity field to date for any planet, including Earth. This detailed information will reveal differences in the density of the moon's crust and mantle and will help answer fundamental questions about the moon's internal structure, thermal evolution, and history of collisions with asteroids. The aim is to map the moon's gravity field so completely that future moon vehicles can safely navigate anywhere on the moon’s surface. For more information, visit http://www.nasa.gov/grail. Photo credit: NASA/Tom Farrar and Tony Gray

CAPE CANAVERAL, Fla. – NASA’s twin Gravity Recovery and Interior Laboratory (GRAIL) mission is moments away from liftoff atop a United Launch Alliance Delta II Heavy rocket. Leaving from Space Launch Complex 17B on Cape Canaveral Air Force Station in Florida, the spacecraft is scheduled to launch at 9:08:52 a.m. EDT Sept.10. GRAIL-A will separate from the second stage of the rocket at about one hour, 21 minutes after liftoff, followed by GRAIL-B at 90 minutes after launch. The spacecraft are embarking on a three-month journey to reach the moon. GRAIL will fly twin spacecraft in tandem around the moon to precisely measure and map variations in the moon's gravitational field. The mission will provide the most accurate global gravity field to date for any planet, including Earth. This detailed information will reveal differences in the density of the moon's crust and mantle and will help answer fundamental questions about the moon's internal structure, thermal evolution, and history of collisions with asteroids. The aim is to map the moon's gravity field so completely that future moon vehicles can safely navigate anywhere on the moon’s surface. For more information, visit http://www.nasa.gov/grail. Photo credit: NASA/Darrell McCall

CAPE CANAVERAL, Fla. – Overlooking the Central Florida coast, engine ignition begins liftoff of the United Launch Alliance Delta II Heavy rocket carrying NASA’s twin Gravity Recovery and Interior Laboratory (GRAIL) mission off Space Launch Complex 17B on Cape Canaveral Air Force Station. The spacecraft launched at 9:08:52 a.m. EDT Sept. 10. GRAIL-A will separate from the second stage of the rocket at about one hour, 21 minutes after liftoff, followed by GRAIL-B at 90 minutes after launch. The spacecraft are embarking on a three-month journey to reach the moon. GRAIL will fly twin spacecraft in tandem around the moon to precisely measure and map variations in the moon's gravitational field. The mission will provide the most accurate global gravity field to date for any planet, including Earth. This detailed information will reveal differences in the density of the moon's crust and mantle and will help answer fundamental questions about the moon's internal structure, thermal evolution, and history of collisions with asteroids. The aim is to map the moon's gravity field so completely that future moon vehicles can safely navigate anywhere on the moon’s surface. For more information, visit http://www.nasa.gov/grail. Photo credit: NASA/Sandra Joseph and Don Kight

CAPE CANAVERAL, Fla. – Plumes of smoke surround of the United Launch Alliance Delta II Heavy rocket carrying NASA’s twin Gravity Recovery and Interior Laboratory (GRAIL) mission off Space Launch Complex 17B on Cape Canaveral Air Force Station in Florida. At right is the pad’s mobile service tower. The spacecraft launched at 9:08:52 a.m. EDT Sept. 10. GRAIL-A will separate from the second stage of the rocket at about one hour, 21 minutes after liftoff, followed by GRAIL-B at 90 minutes after launch. The spacecraft are embarking on a three-month journey to reach the moon. GRAIL will fly twin spacecraft in tandem around the moon to precisely measure and map variations in the moon's gravitational field. The mission will provide the most accurate global gravity field to date for any planet, including Earth. This detailed information will reveal differences in the density of the moon's crust and mantle and will help answer fundamental questions about the moon's internal structure, thermal evolution, and history of collisions with asteroids. The aim is to map the moon's gravity field so completely that future moon vehicles can safely navigate anywhere on the moon’s surface. For more information, visit http://www.nasa.gov/grail. Photo credit: NASA/Tom Farrar and Tony Gray

CAPE CANAVERAL, Fla. – Backdropped by a beautiful blue sky, plumes of smoke surround the United Launch Alliance Delta II Heavy rocket carrying NASA’s twin Gravity Recovery and Interior Laboratory (GRAIL) mission off Space Launch Complex 17B on Cape Canaveral Air Force Station in Florida. The spacecraft launched at 9:08:52 a.m. EDT Sept. 10. GRAIL-A will separate from the second stage of the rocket at about one hour, 21 minutes after liftoff, followed by GRAIL-B at 90 minutes after launch. The spacecraft are embarking on a three-month journey to reach the moon. GRAIL will fly twin spacecraft in tandem around the moon to precisely measure and map variations in the moon's gravitational field. The mission will provide the most accurate global gravity field to date for any planet, including Earth. This detailed information will reveal differences in the density of the moon's crust and mantle and will help answer fundamental questions about the moon's internal structure, thermal evolution, and history of collisions with asteroids. The aim is to map the moon's gravity field so completely that future moon vehicles can safely navigate anywhere on the moon’s surface. For more information, visit http://www.nasa.gov/grail. Photo credit: NASA/Sandra Joseph and Don Kight

CAPE CANAVERAL, Fla. – Engine ignition begins liftoff of the United Launch Alliance Delta II Heavy rocket carrying NASA’s twin Gravity Recovery and Interior Laboratory (GRAIL) mission off Space Launch Complex 17B on Cape Canaveral Air Force Station in Florida. The spacecraft launched at 9:08:52 a.m. EDT Sept. 10. GRAIL-A will separate from the second stage of the rocket at about one hour, 21 minutes after liftoff, followed by GRAIL-B at 90 minutes after launch. The spacecraft are embarking on a three-month journey to reach the moon. GRAIL will fly twin spacecraft in tandem around the moon to precisely measure and map variations in the moon's gravitational field. The mission will provide the most accurate global gravity field to date for any planet, including Earth. This detailed information will reveal differences in the density of the moon's crust and mantle and will help answer fundamental questions about the moon's internal structure, thermal evolution, and history of collisions with asteroids. The aim is to map the moon's gravity field so completely that future moon vehicles can safely navigate anywhere on the moon’s surface. For more information, visit http://www.nasa.gov/grail. Photo credit: NASA/ Tony Gray and Tim Powers

CAPE CANAVERAL, Fla. – Under a blue sky, engine ignition begins liftoff of the United Launch Alliance Delta II Heavy rocket carrying NASA’s twin Gravity Recovery and Interior Laboratory (GRAIL) mission off Space Launch Complex 17B on Cape Canaveral Air Force Station in Florida. The spacecraft launched at 9:08:52 a.m. EDT Sept. 10. GRAIL-A will separate from the second stage of the rocket at about one hour, 21 minutes after liftoff, followed by GRAIL-B at 90 minutes after launch. The spacecraft are embarking on a three-month journey to reach the moon. GRAIL will fly twin spacecraft in tandem around the moon to precisely measure and map variations in the moon's gravitational field. The mission will provide the most accurate global gravity field to date for any planet, including Earth. This detailed information will reveal differences in the density of the moon's crust and mantle and will help answer fundamental questions about the moon's internal structure, thermal evolution, and history of collisions with asteroids. The aim is to map the moon's gravity field so completely that future moon vehicles can safely navigate anywhere on the moon’s surface. For more information, visit http://www.nasa.gov/grail. Photo credit: NASA/Sandra Joseph and Don Kight

CAPE CANAVERAL, Fla. – At liftoff, plumes of smoke surround the United Launch Alliance Delta II Heavy rocket carrying NASA’s twin Gravity Recovery and Interior Laboratory (GRAIL) mission off Space Launch Complex 17B on Cape Canaveral Air Force Station in Florida. The spacecraft launched at 9:08:52 a.m. EDT Sept. 10. GRAIL-A will separate from the second stage of the rocket at about one hour, 21 minutes after liftoff, followed by GRAIL-B at 90 minutes after launch. The spacecraft are embarking on a three-month journey to reach the moon. GRAIL will fly twin spacecraft in tandem around the moon to precisely measure and map variations in the moon's gravitational field. The mission will provide the most accurate global gravity field to date for any planet, including Earth. This detailed information will reveal differences in the density of the moon's crust and mantle and will help answer fundamental questions about the moon's internal structure, thermal evolution, and history of collisions with asteroids. The aim is to map the moon's gravity field so completely that future moon vehicles can safely navigate anywhere on the moon’s surface. For more information, visit http://www.nasa.gov/grail. Photo credit: NASA/ Tony Gray and Tim Powers

CAPE CANAVERAL, Fla. – Backdropped by a beautiful blue sky, the United Launch Alliance Delta II Heavy rocket propels NASA’s twin Gravity Recovery and Interior Laboratory (GRAIL) mission off Space Launch Complex 17B on Cape Canaveral Air Force Station in Florida. The spacecraft launched at 9:08:52 a.m. EDT Sept. 10. GRAIL-A will separate from the second stage of the rocket at about one hour, 21 minutes after liftoff, followed by GRAIL-B at 90 minutes after launch. The spacecraft are embarking on a three-month journey to reach the moon. GRAIL will fly twin spacecraft in tandem around the moon to precisely measure and map variations in the moon's gravitational field. The mission will provide the most accurate global gravity field to date for any planet, including Earth. This detailed information will reveal differences in the density of the moon's crust and mantle and will help answer fundamental questions about the moon's internal structure, thermal evolution, and history of collisions with asteroids. The aim is to map the moon's gravity field so completely that future moon vehicles can safely navigate anywhere on the moon’s surface. For more information, visit http://www.nasa.gov/grail. Photo credit: NASA/Kenny Allen

CAPE CANAVERAL, Fla. – Under a blue sky, engine ignition begins liftoff of the United Launch Alliance Delta II Heavy rocket carrying NASA’s twin Gravity Recovery and Interior Laboratory (GRAIL) mission off Space Launch Complex 17B on Cape Canaveral Air Force Station in Florida. The spacecraft launched at 9:08:52 a.m. EDT Sept. 10. GRAIL-A will separate from the second stage of the rocket at about one hour, 21 minutes after liftoff, followed by GRAIL-B at 90 minutes after launch. The spacecraft are embarking on a three-month journey to reach the moon. GRAIL will fly twin spacecraft in tandem around the moon to precisely measure and map variations in the moon's gravitational field. The mission will provide the most accurate global gravity field to date for any planet, including Earth. This detailed information will reveal differences in the density of the moon's crust and mantle and will help answer fundamental questions about the moon's internal structure, thermal evolution, and history of collisions with asteroids. The aim is to map the moon's gravity field so completely that future moon vehicles can safely navigate anywhere on the moon’s surface. For more information, visit http://www.nasa.gov/grail. Photo credit: NASA/Sandra Joseph and Don Kight

CAPE CANAVERAL, Fla. – At liftoff, plumes of smoke surround the United Launch Alliance Delta II Heavy rocket carrying NASA’s twin Gravity Recovery and Interior Laboratory (GRAIL) mission off Space Launch Complex 17B on Cape Canaveral Air Force Station in Florida. The spacecraft launched at 9:08:52 a.m. EDT Sept. 10. GRAIL-A will separate from the second stage of the rocket at about one hour, 21 minutes after liftoff, followed by GRAIL-B at 90 minutes after launch. The spacecraft are embarking on a three-month journey to reach the moon. GRAIL will fly twin spacecraft in tandem around the moon to precisely measure and map variations in the moon's gravitational field. The mission will provide the most accurate global gravity field to date for any planet, including Earth. This detailed information will reveal differences in the density of the moon's crust and mantle and will help answer fundamental questions about the moon's internal structure, thermal evolution, and history of collisions with asteroids. The aim is to map the moon's gravity field so completely that future moon vehicles can safely navigate anywhere on the moon’s surface. For more information, visit http://www.nasa.gov/grail. Photo credit: NASA/ Tony Gray and Tim Powers

CAPE CANAVERAL, Fla. – At liftoff, flames and smoke from the engines surround the United Launch Alliance Delta II rocket carrying NASA’s twin Gravity Recovery and Interior Laboratory (GRAIL) mission off Space Launch Complex 17B on Cape Canaveral Air Force Station in Florida. The spacecraft launched at 9:08:52 a.m. EDT Sept. 10. GRAIL-A will separate from the second stage of the rocket at about one hour, 21 minutes after liftoff, followed by GRAIL-B at 90 minutes after launch. The spacecraft are embarking on a three-month journey to reach the moon. GRAIL will fly twin spacecraft in tandem around the moon to precisely measure and map variations in the moon's gravitational field. The mission will provide the most accurate global gravity field to date for any planet, including Earth. This detailed information will reveal differences in the density of the moon's crust and mantle and will help answer fundamental questions about the moon's internal structure, thermal evolution, and history of collisions with asteroids. The aim is to map the moon's gravity field so completely that future moon vehicles can safely navigate anywhere on the moon’s surface. For more information, visit http://www.nasa.gov/grail. Photo credit: NASA/ Tony Gray and Tim Powers

CAPE CANAVERAL, Fla. – Rising from fire and smoke under a blue sky, NASA’s twin Gravity Recovery and Interior Laboratory (GRAIL) mission launches atop a United Launch Alliance Delta II Heavy rocket leaving from Space Launch Complex 17B on Cape Canaveral Air Force Station in Florida. Liftoff was at 9:08:52 a.m. EDT Sept. 10. GRAIL-A will separate from the second stage of the rocket at about one hour, 21 minutes after liftoff, followed by GRAIL-B at 90 minutes after launch. The spacecraft are embarking on a three-month journey to reach the moon. GRAIL will fly twin spacecraft in tandem around the moon to precisely measure and map variations in the moon's gravitational field. The mission will provide the most accurate global gravity field to date for any planet, including Earth. This detailed information will reveal differences in the density of the moon's crust and mantle and will help answer fundamental questions about the moon's internal structure, thermal evolution, and history of collisions with asteroids. The aim is to map the moon's gravity field so completely that future moon vehicles can safely navigate anywhere on the moon’s surface. For more information, visit http://www.nasa.gov/grail. Photo credit: NASA/Sandra Joseph and Don Kight

CAPE CANAVERAL, Fla. – The United Launch Alliance Delta II Heavy rocket propels NASA’s twin Gravity Recovery and Interior Laboratory (GRAIL) mission into the clouds over Space Launch Complex 17B on Cape Canaveral Air Force Station in Florida. The spacecraft launched at 9:08:52 a.m. EDT Sept. 10. GRAIL-A will separate from the second stage of the rocket at about one hour, 21 minutes after liftoff, followed by GRAIL-B at 90 minutes after launch. The spacecraft are embarking on a three-month journey to reach the moon. GRAIL will fly twin spacecraft in tandem around the moon to precisely measure and map variations in the moon's gravitational field. The mission will provide the most accurate global gravity field to date for any planet, including Earth. This detailed information will reveal differences in the density of the moon's crust and mantle and will help answer fundamental questions about the moon's internal structure, thermal evolution, and history of collisions with asteroids. The aim is to map the moon's gravity field so completely that future moon vehicles can safely navigate anywhere on the moon’s surface. For more information, visit http://www.nasa.gov/grail. Photo credit: NASA/Kenny Allen

CAPE CANAVERAL, Fla. – Backdropped by a beautiful blue sky, the United Launch Alliance Delta II Heavy rocket propels NASA’s twin Gravity Recovery and Interior Laboratory (GRAIL) mission off Space Launch Complex 17B on Cape Canaveral Air Force Station in Florida. The spacecraft launched at 9:08:52 a.m. EDT Sept. 10. GRAIL-A will separate from the second stage of the rocket at about one hour, 21 minutes after liftoff, followed by GRAIL-B at 90 minutes after launch. The spacecraft are embarking on a three-month journey to reach the moon. GRAIL will fly twin spacecraft in tandem around the moon to precisely measure and map variations in the moon's gravitational field. The mission will provide the most accurate global gravity field to date for any planet, including Earth. This detailed information will reveal differences in the density of the moon's crust and mantle and will help answer fundamental questions about the moon's internal structure, thermal evolution, and history of collisions with asteroids. The aim is to map the moon's gravity field so completely that future moon vehicles can safely navigate anywhere on the moon’s surface. For more information, visit http://www.nasa.gov/grail. Photo credit: NASA/Kenny Allen

CAPE CANAVERAL, Fla. – Plumes of smoke surround of the United Launch Alliance Delta II Heavy rocket carrying NASA’s twin Gravity Recovery and Interior Laboratory (GRAIL) mission off Space Launch Complex 17B on Cape Canaveral Air Force Station In Florida. The spacecraft launched at 9:08:52 a.m. EDT Sept. 10. GRAIL-A will separate from the second stage of the rocket at about one hour, 21 minutes after liftoff, followed by GRAIL-B at 90 minutes after launch. The spacecraft are embarking on a three-month journey to reach the moon. GRAIL will fly twin spacecraft in tandem around the moon to precisely measure and map variations in the moon's gravitational field. The mission will provide the most accurate global gravity field to date for any planet, including Earth. This detailed information will reveal differences in the density of the moon's crust and mantle and will help answer fundamental questions about the moon's internal structure, thermal evolution, and history of collisions with asteroids. The aim is to map the moon's gravity field so completely that future moon vehicles can safely navigate anywhere on the moon’s surface. For more information, visit http://www.nasa.gov/grail. Photo credit: NASA/Sandra Joseph and Don Kight

CAPE CANAVERAL, Fla. – Engine ignition begins liftoff of the United Launch Alliance Delta II Heavy rocket carrying NASA’s twin Gravity Recovery and Interior Laboratory (GRAIL) mission off Space Launch Complex 17B on Cape Canaveral Air Force Station in Florida. The spacecraft launched at 9:08:52 a.m. EDT Sept. 10. GRAIL-A will separate from the second stage of the rocket at about one hour, 21 minutes after liftoff, followed by GRAIL-B at 90 minutes after launch. The spacecraft are embarking on a three-month journey to reach the moon. GRAIL will fly twin spacecraft in tandem around the moon to precisely measure and map variations in the moon's gravitational field. The mission will provide the most accurate global gravity field to date for any planet, including Earth. This detailed information will reveal differences in the density of the moon's crust and mantle and will help answer fundamental questions about the moon's internal structure, thermal evolution, and history of collisions with asteroids. The aim is to map the moon's gravity field so completely that future moon vehicles can safely navigate anywhere on the moon’s surface. For more information, visit http://www.nasa.gov/grail. Photo credit: NASA/ Tony Gray and Tim Powers

CAPE CANAVERAL, Fla. – Flames and smoke from the engines surround the United Launch Alliance Delta II rocket at liftoff carrying NASA’s twin Gravity Recovery and Interior Laboratory (GRAIL) mission off Space Launch Complex 17B on Cape Canaveral Air Force Station in Florida. The spacecraft launched at 9:08:52 a.m. EDT Sept. 10. GRAIL-A will separate from the second stage of the rocket at about one hour, 21 minutes after liftoff, followed by GRAIL-B at 90 minutes after launch. The spacecraft are embarking on a three-month journey to reach the moon. GRAIL will fly twin spacecraft in tandem around the moon to precisely measure and map variations in the moon's gravitational field. The mission will provide the most accurate global gravity field to date for any planet, including Earth. This detailed information will reveal differences in the density of the moon's crust and mantle and will help answer fundamental questions about the moon's internal structure, thermal evolution, and history of collisions with asteroids. The aim is to map the moon's gravity field so completely that future moon vehicles can safely navigate anywhere on the moon’s surface. For more information, visit http://www.nasa.gov/grail. Photo credit: NASA/Sandra Joseph and Don Kight

CAPE CANAVERAL, Fla. – Fire lights up a blue sky on Space Launch Complex 17B on Cape Canaveral Air Force Station in Florida as a United Launch Alliance Delta II Heavy rocket lofts the Gravity Recovery and Interior Laboratory (GRAIL) mission into space. Liftoff was at 9:08:52 a.m. EDT Sept.10. GRAIL-A will separate from the second stage of the rocket at about one hour, 21 minutes after liftoff, followed by GRAIL-B at 90 minutes after launch. The spacecraft are embarking on a three-month journey to reach the moon. GRAIL will fly twin spacecraft in tandem around the moon to precisely measure and map variations in the moon's gravitational field. The mission will provide the most accurate global gravity field to date for any planet, including Earth. This detailed information will reveal differences in the density of the moon's crust and mantle and will help answer fundamental questions about the moon's internal structure, thermal evolution, and history of collisions with asteroids. The aim is to map the moon's gravity field so completely that future moon vehicles can safely navigate anywhere on the moon’s surface. For more information, visit http://www.nasa.gov/grail. Photo credit: NASA/Fletcher Hildreth

CAPE CANAVERAL, Fla. – Fire and smoke light up the sky as a United Launch Alliance Delta II Heavy rocket propels NASA’s Gravity Recovery and Interior Laboratory (GRAIL) mission into space. Liftoff from Space Launch Complex 17B on Cape Canaveral Air Force Station in Florida was at 9:08:52 a.m. EDT Sept.10. GRAIL-A will separate from the second stage of the rocket at about one hour, 21 minutes after liftoff, followed by GRAIL-B at 90 minutes after launch. The spacecraft are embarking on a three-month journey to reach the moon. GRAIL will fly twin spacecraft in tandem around the moon to precisely measure and map variations in the moon's gravitational field. The mission will provide the most accurate global gravity field to date for any planet, including Earth. This detailed information will reveal differences in the density of the moon's crust and mantle and will help answer fundamental questions about the moon's internal structure, thermal evolution, and history of collisions with asteroids. The aim is to map the moon's gravity field so completely that future moon vehicles can safely navigate anywhere on the moon’s surface. For more information, visit http://www.nasa.gov/grail. Photo credit: NASA/Darrell McCall

CAPE CANAVERAL, Fla. – The United Launch Alliance Delta II Heavy rocket propels NASA’s twin Gravity Recovery and Interior Laboratory (GRAIL) mission into the clouds over Space Launch Complex 17B on Cape Canaveral Air Force Station in Florida. Liftoff was at 9:08:52 a.m. EDT Sept.10. GRAIL-A will separate from the second stage of the rocket at about one hour 21 minutes after liftoff, followed by GRAIL-B at 90-minutes after launch. The spacecraft are embarking on a three-month journey to reach the moon. GRAIL will fly twin spacecraft in tandem around the moon to precisely measure and map variations in the moon's gravitational field. The mission will provide the most accurate global gravity field to date for any planet, including Earth. This detailed information will reveal differences in the density of the moon's crust and mantle and will help answer fundamental questions about the moon's internal structure, thermal evolution, and history of collisions with asteroids. The aim is to map the moon's gravity field so completely that future moon vehicles can safely navigate anywhere on the moon’s surface. For more information, visit http://www.nasa.gov/grail. Photo credit: NASA/Darrell McCall

CAPE CANAVERAL, Fla. –The United Launch Alliance Delta II Heavy rocket propels NASA’s twin Gravity Recovery and Interior Laboratory (GRAIL) mission into the clouds over Space Launch Complex 17B on Cape Canaveral Air Force Station in Florida. Liftoff was at 9:08:52 a.m. EDT Sept.10. GRAIL-A will separate from the second stage of the rocket at about one hour, 21 minutes after liftoff, followed by GRAIL-B at 90 minutes after launch. The spacecraft are embarking on a three-month journey to reach the moon. GRAIL will fly twin spacecraft in tandem around the moon to precisely measure and map variations in the moon's gravitational field. The mission will provide the most accurate global gravity field to date for any planet, including Earth. This detailed information will reveal differences in the density of the moon's crust and mantle and will help answer fundamental questions about the moon's internal structure, thermal evolution, and history of collisions with asteroids. The aim is to map the moon's gravity field so completely that future moon vehicles can safely navigate anywhere on the moon’s surface. For more information, visit http://www.nasa.gov/grail. Photo credit: NASA/Fletcher Hildreth

CAPE CANAVERAL, Fla. – Fire and smoke light up a blue sky as a United Launch Alliance Delta II Heavy rocket propels NASA’s Gravity Recovery and Interior Laboratory (GRAIL) mission into space. Liftoff from Space Launch Complex 17B on Cape Canaveral Air Force Station in Florida was at 9:08:52 a.m. EDT Sept.10. GRAIL-A will separate from the second stage of the rocket at about one hour, 21 minutes after liftoff, followed by GRAIL-B at 90 minutes after launch. The spacecraft are embarking on a three-month journey to reach the moon. GRAIL will fly twin spacecraft in tandem around the moon to precisely measure and map variations in the moon's gravitational field. The mission will provide the most accurate global gravity field to date for any planet, including Earth. This detailed information will reveal differences in the density of the moon's crust and mantle and will help answer fundamental questions about the moon's internal structure, thermal evolution, and history of collisions with asteroids. The aim is to map the moon's gravity field so completely that future moon vehicles can safely navigate anywhere on the moon’s surface. For more information, visit http://www.nasa.gov/grail. Photo credit: NASA/Darrell McCall

CAPE CANAVERAL, Fla. –The United Launch Alliance Delta II Heavy rocket propels NASA’s twin Gravity Recovery and Interior Laboratory (GRAIL) mission into the clouds over Space Launch Complex 17B on Cape Canaveral Air Force Station in Florida. Liftoff was at 9:08:52 a.m. EDT Sept.10. GRAIL-A will separate from the second stage of the rocket at about one hour, 21 minutes after liftoff, followed by GRAIL-B at 90 minutes after launch. The spacecraft are embarking on a three-month journey to reach the moon. GRAIL will fly twin spacecraft in tandem around the moon to precisely measure and map variations in the moon's gravitational field. The mission will provide the most accurate global gravity field to date for any planet, including Earth. This detailed information will reveal differences in the density of the moon's crust and mantle and will help answer fundamental questions about the moon's internal structure, thermal evolution, and history of collisions with asteroids. The aim is to map the moon's gravity field so completely that future moon vehicles can safely navigate anywhere on the moon’s surface. For more information, visit http://www.nasa.gov/grail. Photo credit: NASA/Fletcher Hildreth

CAPE CANAVERAL, Fla. – Plumes of smoke surround Space Launch Complex 17B on Cape Canaveral Air Force Station in Florida as a United Launch Alliance Delta II Heavy rocket lofts NASA’s Gravity Recovery and Interior Laboratory (GRAIL) mission into space. Liftoff was at 9:08:52 a.m. EDT Sept.10. GRAIL-A will separate from the second stage of the rocket at about one hour, 21 minutes after liftoff, followed by GRAIL-B at 90 minutes after launch. The spacecraft are embarking on a three-month journey to reach the moon. GRAIL will fly twin spacecraft in tandem around the moon to precisely measure and map variations in the moon's gravitational field. The mission will provide the most accurate global gravity field to date for any planet, including Earth. This detailed information will reveal differences in the density of the moon's crust and mantle and will help answer fundamental questions about the moon's internal structure, thermal evolution, and history of collisions with asteroids. The aim is to map the moon's gravity field so completely that future moon vehicles can safely navigate anywhere on the moon’s surface. For more information, visit http://www.nasa.gov/grail. Photo credit: NASA/Darrell McCall

CAPE CANAVERAL, Fla. – Fire lights up the sky as a United Launch Alliance Delta II Heavy rocket lofts NASA’s Gravity Recovery and Interior Laboratory (GRAIL) mission into space. Liftoff from Space Launch Complex 17B on Cape Canaveral Air Force Station in Florida was at 9:08:52 a.m. EDT Sept.10. GRAIL-A will separate from the second stage of the rocket at about one hour, 21 minutes after liftoff, followed by GRAIL-B at 90 minutes after launch. The spacecraft are embarking on a three-month journey to reach the moon. GRAIL will fly twin spacecraft in tandem around the moon to precisely measure and map variations in the moon's gravitational field. The mission will provide the most accurate global gravity field to date for any planet, including Earth. This detailed information will reveal differences in the density of the moon's crust and mantle and will help answer fundamental questions about the moon's internal structure, thermal evolution, and history of collisions with asteroids. The aim is to map the moon's gravity field so completely that future moon vehicles can safely navigate anywhere on the moon’s surface. For more information, visit http://www.nasa.gov/grail. Photo credit: NASA/Darrell McCall

KENNEDY SPACE CENTER, FLA. - The Delta II launch vehicle carrying the STEREO spacecraft hurtles through the smoke and steam after liftoff from Launch Pad 17-B at Cape Canaveral Air Force Station. Liftoff was at 8:52 p.m. EDT. STEREO (Solar Terrestrial Relations Observatory) is a two-year mission using two nearly identical observatories, one ahead of Earth in its orbit and the other trailing behind. The duo will provide 3-D measurements of the sun and its flow of energy, enabling scientists to study the nature of coronal mass ejections and why they happen. The ejections are a major source of the magnetic disruptions on Earth and are a key component of space weather. The disruptions can greatly effect satellite operations, communications, power systems, humans in space and global climate. Designed and built by the Johns Hopkins University Applied Physics Laboratory (APL) , the STEREO mission is being managed by NASA Goddard Space Flight Center. APL will maintain command and control of the observatories throughout the mission, while NASA tracks and receives the data, determines the orbit of the satellites, and coordinates the science results.

KENNEDY SPACE CENTER, FLA. - The Banana River reflects the brilliant launch of the Delta II carrying the STEREO spacecraft. Liftoff from Launch Pad 17-B at Cape Canaveral Air Force Station was at 8:52 p.m. EDT. STEREO (Solar Terrestrial Relations Observatory) is a two-year mission using two nearly identical observatories, one ahead of Earth in its orbit and the other trailing behind. The duo will provide 3-D measurements of the sun and its flow of energy, enabling scientists to study the nature of coronal mass ejections and why they happen. The ejections are a major source of the magnetic disruptions on Earth and are a key component of space weather. The disruptions can greatly effect satellite operations, communications, power systems, humans in space and global climate. Designed and built by the Johns Hopkins University Applied Physics Laboratory (APL) , the STEREO mission is being managed by NASA Goddard Space Flight Center. APL will maintain command and control of the observatories throughout the mission, while NASA tracks and receives the data, determines the orbit of the satellites, and coordinates the science results. Photo credit: NASA/Jim Grossmann

KENNEDY SPACE CENTER, FLA. - Just after liftoff, clouds of smoke billow up and around the Delta II rocket carrying the STEREO spacecraft on top. Liftoff from Launch Pad 17-B at Cape Canaveral Air Force Station was at 8:52 p.m. EDT. STEREO (Solar Terrestrial Relations Observatory) is a two-year mission using two nearly identical observatories, one ahead of Earth in its orbit and the other trailing behind. The duo will provide 3-D measurements of the sun and its flow of energy, enabling scientists to study the nature of coronal mass ejections and why they happen. The ejections are a major source of the magnetic disruptions on Earth and are a key component of space weather. The disruptions can greatly effect satellite operations, communications, power systems, humans in space and global climate. Designed and built by the Johns Hopkins University Applied Physics Laboratory (APL) , the STEREO mission is being managed by NASA Goddard Space Flight Center. APL will maintain command and control of the observatories throughout the mission, while NASA tracks and receives the data, determines the orbit of the satellites, and coordinates the science results.

KENNEDY SPACE CENTER, FLA. - At liftoff, clouds of smoke spread beneath the Delta II rocket carrying the STEREO spacecraft on top. Liftoff from Launch Pad 17-B at Cape Canaveral Air Force Station was at 8:52 p.m. EDT. STEREO (Solar Terrestrial Relations Observatory) is a two-year mission using two nearly identical observatories, one ahead of Earth in its orbit and the other trailing behind. The duo will provide 3-D measurements of the sun and its flow of energy, enabling scientists to study the nature of coronal mass ejections and why they happen. The ejections are a major source of the magnetic disruptions on Earth and are a key component of space weather. The disruptions can greatly effect satellite operations, communications, power systems, humans in space and global climate. Designed and built by the Johns Hopkins University Applied Physics Laboratory (APL) , the STEREO mission is being managed by NASA Goddard Space Flight Center. APL will maintain command and control of the observatories throughout the mission, while NASA tracks and receives the data, determines the orbit of the satellites, and coordinates the science results.

KENNEDY SPACE CENTER, FLA. - Captured in the water of the Banana River, the brilliant light from the Delta II carrying the STEREO spacecraft lights up the night sky. Liftoff from Launch Pad 17-B at Cape Canaveral Air Force Station was at 8:52 p.m. EDT. STEREO (Solar Terrestrial Relations Observatory) is a two-year mission using two nearly identical observatories, one ahead of Earth in its orbit and the other trailing behind. The duo will provide 3-D measurements of the sun and its flow of energy, enabling scientists to study the nature of coronal mass ejections and why they happen. The ejections are a major source of the magnetic disruptions on Earth and are a key component of space weather. The disruptions can greatly effect satellite operations, communications, power systems, humans in space and global climate. Designed and built by the Johns Hopkins University Applied Physics Laboratory (APL) , the STEREO mission is being managed by NASA Goddard Space Flight Center. APL will maintain command and control of the observatories throughout the mission, while NASA tracks and receives the data, determines the orbit of the satellites, and coordinates the science results. Photo credit: NASA/Jim Grossmann

KENNEDY SPACE CENTER, FLA. - The Delta II rocket carrying the STEREO spacecraft on top streaks through the smoke as it climbs to orbit. Liftoff from Launch Pad 17-B at Cape Canaveral Air Force Station was at 8:52 p.m. EDT. STEREO (Solar Terrestrial Relations Observatory) is a two-year mission using two nearly identical observatories, one ahead of Earth in its orbit and the other trailing behind. The duo will provide 3-D measurements of the sun and its flow of energy, enabling scientists to study the nature of coronal mass ejections and why they happen. The ejections are a major source of the magnetic disruptions on Earth and are a key component of space weather. The disruptions can greatly effect satellite operations, communications, power systems, humans in space and global climate. Designed and built by the Johns Hopkins University Applied Physics Laboratory (APL) , the STEREO mission is being managed by NASA Goddard Space Flight Center. APL will maintain command and control of the observatories throughout the mission, while NASA tracks and receives the data, determines the orbit of the satellites, and coordinates the science results.

KENNEDY SPACE CENTER, FLA. - Just after liftoff, clouds of smoke billow up and around the Delta II rocket carrying the STEREO spacecraft on top. Liftoff from Launch Pad 17-B at Cape Canaveral Air Force Station was at 8:52 p.m. EDT. STEREO (Solar Terrestrial Relations Observatory) is a two-year mission using two nearly identical observatories, one ahead of Earth in its orbit and the other trailing behind. The duo will provide 3-D measurements of the sun and its flow of energy, enabling scientists to study the nature of coronal mass ejections and why they happen. The ejections are a major source of the magnetic disruptions on Earth and are a key component of space weather. The disruptions can greatly effect satellite operations, communications, power systems, humans in space and global climate. Designed and built by the Johns Hopkins University Applied Physics Laboratory (APL) , the STEREO mission is being managed by NASA Goddard Space Flight Center. APL will maintain command and control of the observatories throughout the mission, while NASA tracks and receives the data, determines the orbit of the satellites, and coordinates the science results.

KENNEDY SPACE CENTER, FLA. - Just at liftoff, clouds of smoke and steam rise around the Delta II rocket carrying the STEREO spacecraft on top. Liftoff from Launch Pad 17-B at Cape Canaveral Air Force Station was at 8:52 p.m. EDT. STEREO (Solar Terrestrial Relations Observatory) is a two-year mission using two nearly identical observatories, one ahead of Earth in its orbit and the other trailing behind. The duo will provide 3-D measurements of the sun and its flow of energy, enabling scientists to study the nature of coronal mass ejections and why they happen. The ejections are a major source of the magnetic disruptions on Earth and are a key component of space weather. The disruptions can greatly effect satellite operations, communications, power systems, humans in space and global climate. Designed and built by the Johns Hopkins University Applied Physics Laboratory (APL) , the STEREO mission is being managed by NASA Goddard Space Flight Center. APL will maintain command and control of the observatories throughout the mission, while NASA tracks and receives the data, determines the orbit of the satellites, and coordinates the science results.

Former NASA astronaut C. Gordon Fullerton, seated in the cockpit of an F/A-18, is a research pilot at NASA's Dryden Flight Research Center, Edwards, Calif. Since transferring to Dryden in 1986, his assignments have included a variety of flight research and support activities piloting NASA's B-52 launch aircraft, the 747 Shuttle Carrier Aircraft (SCA), and other multi-engine and high performance aircraft. He flew a series of development air launches of the X-38 prototype Crew Return Vehicle and in the launches for the X-43A Hyper-X project. Fullerton also flies Dryden's DC-8 Airborne Science aircraft in support a variety of atmospheric physics, ground mapping and meteorology studies. Fullerton also was project pilot on the Propulsion Controlled Aircraft program, during which he successfully landed both a modified F-15 and an MD-11 transport with all control surfaces neutralized, using only engine thrust modulation for control. Fullerton also evaluated the flying qualities of the Russian Tu-144 supersonic transport during two flights in 1998, one of only two non-Russian pilots to fly that aircraft. With more than 15,000 hours of flying time, Fullerton has piloted 135 different types of aircraft in his career. As an astronaut, Fullerton served on the support crews for the Apollo 14, 15, 16, and 17 lunar missions. In 1977, Fullerton was on one of the two flight crews that piloted the Space Shuttle prototype Enterprise during the Approach and Landing Test Program at Dryden. Fullerton was the pilot on the STS-3 Space Shuttle orbital flight test mission in 1982, and commanded the STS-51F Spacelab 2 mission in 1985. He has logged 382 hours in space flight. In July 1988, he completed a 30-year career with the U.S. Air Force and retired as a colonel.

The HL-10 was one of five heavyweight lifting-body designs flown at NASA's Flight Research Center (FRC--later Dryden Flight Research Center), Edwards, California, from July 1966 to November 1975 to study and validate the concept of safely maneuvering and landing a low lift-over-drag vehicle designed for reentry from space. Northrop Corporation built the HL-10 and M2-F2, the first two of the fleet of "heavy" lifting bodies flown by the NASA Flight Research Center. The contract for construction of the HL-10 and the M2-F2 was $1.8 million. "HL" stands for horizontal landing, and "10" refers to the tenth design studied by engineers at NASA's Langley Research Center, Hampton, Va. After delivery to NASA in January 1966, the HL-10 made its first flight on Dec. 22, 1966, with research pilot Bruce Peterson in the cockpit. Although an XLR-11 rocket engine was installed in the vehicle, the first 11 drop flights from the B-52 launch aircraft were powerless glide flights to assess handling qualities, stability, and control. In the end, the HL-10 was judged to be the best handling of the three original heavy-weight lifting bodies (M2-F2/F3, HL-10, X-24A). The HL-10 was flown 37 times during the lifting body research program and logged the highest altitude and fastest speed in the Lifting Body program. On Feb. 18, 1970, Air Force test pilot Peter Hoag piloted the HL-10 to Mach 1.86 (1,228 mph). Nine days later, NASA pilot Bill Dana flew the vehicle to 90,030 feet, which became the highest altitude reached in the program. Some new and different lessons were learned through the successful flight testing of the HL-10. These lessons, when combined with information from it's sister ship, the M2-F2/F3, provided an excellent starting point for designers of future entry vehicles, including the Space Shuttle.