Side close-up view of crewman in high-fidelity Extravehicular Mobility Unit (EMU) / Manned Maneuvering Unit (MMU) mockup.

Astronaut Bruce McCandless during an underwater test of the Manned Maneuvering Unit (MMU) Flight Support Station (FSS) donning and doffing in the Bldg 29 Weightless Environment Training Facility (WETF). View is of McCandless wearing the extravehicular mobility unit (EMU), stepping into the MMU.

41C-22-885 (8 April 1984) --- The 35mm camera was used to photograph this scene of Astronaut George D. Nelson, STS-41C mission specialist, as he uses the manned maneuvering unit (MMU) to make an excursion to the plagued Solar Maximum, Mission Satellite (SMMS)._Astronaut James D. van Hoften remained in the Challenger's cargo bay during the April 8 extravehicular activity (EVA).

S84-27022 (7 Feb 1984) --- A 35mm frame from the February 7, 1984, extravehicular activity (EVA) photographed with a camera affixed to the gear of astronaut Bruce McCandless II. The mission specialist was equipped with the nitrogen-propelled, hand-controlled Manned Maneuvering Unit (MMU), which took him some 90 meters away from the Space Shuttle Challenger. This scene is reminiscent of views of the Challenger during the June 1983, STS-7 flight, on which the Shuttle Pallet Satellite (SPAS - seen here in the middle of the cargo bay) provided scenes of 38-meter-long reusable vehicle over the Earth.

S84-27031 (7 Feb 1984) --- Astronaut Bruce McCandless II, 41-B mission specialist, reaches a maximum distance from the Challenger before reversing direction his manned maneuvering unit (MMU) and returning to the Challenger. A fellow crewmember inside the vehicle's cabin took this photograph with a 70mm camera. The untethered EVA marked the first such experience for astronauts.

51A-104-008 (14 Nov 1984) --- Astronaut Dale A. Gardner appears to be under the remote manipulator system (RMS) end effector as he makes a turn in space and prepared to traverse, using the manned maneuvering unit (MMU) backpack, to the nearby Westar VI to "Sting" it with the device he carries. The stringer will enter the communications satellite through the nozzle of the spent motor. Gardner achieved a hard dock at 6:32 A.M. and this picture was photographed about five minutes earlier, on Nov. 14, 1984.

S84-27023 (7 Feb 1984) --- This 70mm frame shows astronaut Bruce McCandless II moving in to conduct a test involving the Trunion Pin Attachment Device (TPAD) he carries and the Shuttle Pallet Satellite (SPAS-01A) partially visible at bottom of frame. SPAS was a stand-in for the damaged Solar Maximum Satellite (SMS) which will be visited for repairs by the STS-41C Shuttle crew in early spring. This particular Extravehicular Activity (EVA) session was a rehearsal for the SMS visit. The test and the actual visit to the SMS both involve the use of jet-powered, hand-controlled Manned Maneuvering Unit (MMU). The one McCandless uses is the second unit to be tested on this flight. Astronaut Robert L. Stewart got a chance to work with both MMU's on the two EVA's.

S84-27021 (7 Feb 1984) --- Astronaut Bruce McCandless II, 41B mission specialist tests a "cherry-picker" type device during February 7 historical Extravehicular Activity (EVA). The EVA, in which Astronauts McCandless and Robert L. Stewart, two of three STS-41B mission specialists, participated, marked two firsts--initial use of both the Mobile Foot Restraint (MFR) attached to the Remote Manipulator System (RMS) arm here, and the Manned Maneuvering Unit (MMU) backpack (not seen in this frame). The Challenger was flying with its aft end aimed toward the Earth. This photograph clearly shows where the MFR connects to the end effector of the Canadian-built RMS arm. The two spacewalkers were monitored and photographed by their fellow crewmembers, astronauts Vance D. Brand, commander; Robert L. Gibson, pilot; and Ronald E. McNair, mission specialist. The three remained in the cabin for another EVA session two days later. Photo Credit: NASA

S93-50137 (December 1993) --- This small mobility-aiding back harness, complemented in extravehicular activity (EVA) with a hand controller unit and called the Simplified Aid for EVA Rescue (SAFER) system, will get extensive in-space evaluation and testing during the STS-64 mission. In this view the SAFER is open to reveal the gas supply and thrusters. SAFER is to fly on STS-76 as well.

Portrait photographs of STS-11/41B Crewman Robert L. Stewart, wearing the Extravehicular Maneuvering Unit (EMU) with the Manned Manuevering Unit (MMU) attached, and without helmet.

S80-36848 (24 July 1980) --- Photo of the Manned Maneuvering Unit (MMU) simulator at the Martin Marietta plant in Denver, Colorado. View of simulator with test subject strapped in to it.

S82-27594 (25 Feb 1982) --- Astronaut Bruce McCandless II models NASA?s extravehicular mobility unit (EMU) spacesuit for Shuttle and the backpack unit (called a manned maneuvering unit) that will give future STS crewmembers extended mobility in space. A forerunner version of the MMU?called an astronaut maneuvering unit?was tested internally on Skylab. The MMU will allow astronauts for the first time in history to move about in the vicinity of their spacecraft without being tethered to the ship. McCandless was giving a demonstration of the EMU/MMU in JSC?s laboratory support facility.

S66-31019 (May 1966) --- Test subject Fred Spross, Crew Systems Division, wears the Gemini-9 configured extravehicular spacesuit assembly. The legs are covered with Chromel R, which is a cloth woven from stainless steel fibers, used to protect the astronaut and suit from the hot exhaust thrust of the Astronaut Maneuvering Unit (AMU). Astronaut Eugene A. Cernan will wear this spacesuit during his Gemini-9A extravehicular activity (EVA). Photo credit: NASA

Astronaut Dale A. Gardner, 51-A mission specialist, rehearses control of manned maneuvering unit (MMU) during a practice for an extravehicular activity (EVA). Gardner is in the Shuttle mockup and integration laboratory at JSC. Gardner handles a stinger device to make initial contact with one of the two satellites they will be working with.

S66-19284 (1 Feb. 1966) --- Astronaut David R. Scott practicing for Gemini-8 extravehicular activity (EVA) in building 4 of the Manned Spacecraft Center on the air bearing floor. He is wearing the Hand-Held Maneuvering Unit which he will use during the EVA. Photo credit: NASA

S80-36844 (24 July 1980) --- Manned Maneuvering Unit (MMU) development at the Martin Marietta plant in Denver, Colorado. View shows MMU prototype with astronaut AnnaL. Fisher serving as test subject strapped in to it. Photo credit: NASA

SL3-107-1215 (27 Aug. 1973) --- Astronaut Alan L. Bean, Skylab 3 commander, flies the M509 Astronaut Maneuvering Equipment in the forward dome area of the Orbital Workshop (OWS) on the space station cluster in Earth orbit. One of his fellow crewmen took this photograph with a 35mm Nikon camera. Bean is strapped into the back mounted, hand-controlled Automatically Stabilized Maneuvering Unit (ASMU). The dome area is about 22 feet in diameter and 19 feet from top to bottom. Photo credit: NASA

SL3-108-1304 (July-September 1973) --- Astronaut Alan L. Bean, Skylab 3 commander, flies the M509 Astronaut Maneuvering Equipment in the forward dome area of the Orbital Workshop (OWS) on the space station cluster in Earth orbit. Bean is strapped in to the back-mounted, hand-controlled Automatically Stabilized Maneuvering Unit (ASMU). This ASMU experiment is being done in shirt sleeves. The dome area where the experiment is conducted is about 22 feet in diameter and 19 feet from top to bottom. Photo credit: NASA

S73-34207 (28 Aug. 1973) --- Astronaut Alan L. Bean, Skylab 3 commander, flies the M509 astronaut Maneuvering Equipment, as seen in this photographic reproduction taken from a television transmission made by a color television camera in the Orbital Workshop (OWS) of the Skylab space station in Earth orbit. Bean is strapped into the back-mounted, hand-controlled Automatically Stabilized Maneuvering Unit (ASMU). The M509 exercise was in the forward dome area of the OWS. The dome area is about 22 feet in diameter and 19 feet from top to bottom. Photo credit: NASA

S93-26918 (8 Sept. 1994) --- Scott Bleisath, an extravehicular activity (EVA) engineer, demonstrates the hand control module for the Simplified Aid for EVA Rescue (SAFER) system making its first flight on the scheduled September STS-64 mission. Astronauts Mark C. Lee and Carl J. Meade are the spacewalkers assigned to test the system in space. Unidentified technicians and engineers look on. Photo credit: NASA or National Aeronautics and Space Administration

S93-26920 (8 Sept. 1994) --- Scott Bleisath, an extravehicular activity (EVA) engineer, demonstrates the hand control module for the Simplified Aid for EVA Rescue (SAFER) system making its first flight on the scheduled September STS-64 mission. Astronauts Mark C. Lee and Carl J. Meade are the spacewalkers assigned to test the system in space. Photo credit: NASA or National Aeronautics and Space Administration

S84-27232 (& Feb 1984) --- Astronaut Bruce McCandless II, 41-B mission specialist, uses his hands to control his movement above the Earth - and just few meters away from the Challenger - during the first-ever extravehicular activity (EVA) which didn?t use restrictive tethers and umbilical?s. Fellow crewmembers aboard the Challenger used a 70mm camera to expose this frame through windows on the flight deck. McCandless was joined by Robert L. Stewart, one of two other mission specialists for this flight, on two sessions of EVA.

CAPE CANAVERAL, Fla. – At the Apollo/Saturn V Center at NASA's Kennedy Space Center in Florida, Apollo astronauts (from left) Buzz Aldrin, Walt Cunningham, Edgar Mitchell, Al Worden, Charlie Duke, Vance Brand and Gerald Carr applaud the addition of Apollo astronaut Bruce McCandless on stage for NASA's 40th Anniversary of Apollo Celebration of the July 1969 launch and landing on the moon. McCandless was a member of the astronaut support crew for the Apollo 14 mission and was backup pilot for the first manned Skylab mission. Among other accomplishments, he collaborated on the development of the Manned Maneuvering Unit used during shuttle EVAs. Photo credit: NASA/Kim Shiflett

S80-36889 (24 July 1980) --- Astronaut Bruce McCandless II uses a simulator at Martin Marietta?s space center near Denver to develop flight techniques for a backpack propulsion unit that will be used on Space Shuttle flights. The manned maneuvering unit (MMU) training simulator allows astronauts to "fly missions" against a full scale mockup of a portion of the orbiter vehicle. Controls of the simulator are like those of the actual MMU. Manipulating them allows the astronaut to move in three straight-line directions and in pitch, yaw and roll. One possible application of the MMU is for an extravehicular activity chore to repair damaged tiles on the vehicle. McCandless is wearing an extravehicular mobility unit (EMU).

S84-27034A (9 Feb. 1984) --- Astronaut Robert L. Stewart appears to glide a few meters above the Earth-orbiting Space Shuttle Challenger's cargo bay during the second of two extravehicular activity (EVA) session on the Challenger's fourth flight in space. Astronauts Stewart and Bruce McCandless II, two of NASA's three mission specialists on flight STS-41B, earlier made another EVA, testing another manned maneuvering unit (MMU).

Astronaut Robert L. Stewart, Mission Specialist (MS), uses his hands to control his movement in space while using the nitrogen propelled Manned Maneuvering Unit (MMU). He is participating in a EVA, a few meters away from the cabin of the Shuttle Challenger. MS Stewart is centered in a background of clouds and Earth in this view of his EVA. He is floating without tethers attaching him to the Shuttle.

41C-37-1718 (11 April 1984) --- Astronaut James D. van Hoften and a repaired satellite are captured by a Hasselblad camera aimed through Challenger's aft cabin windows toward the cargo bay of the Earth orbiting Challenger. Dr. van Hoften is getting in his first "field" test of the manned maneuvering unit (MMU) after months of training in an underwater facility and in a simulator on Earth. The Solar Maximum Mission Satellite (SMMS), revived and almost ready for release into space once more, is docked at the flight support system (FSS).

41C-34-1380 (10-11 April 1984) --- Astronaut George D. Nelson, using the manned maneuvering unit (MMU), arrives at the ailing Solar Maximum Mission Satellite (SMMS). After the STS-41C crewmembers captured the errant satellite and temporarily cradled it in Challenger?s payload bay, astronauts Nelson and James D. van Hoften repaired it and later re-released it.

51A-39-034 (14 Nov. 1984) --- A 70mm frame of astronaut Dale A. Gardner, wearing the Manned Maneuvering Unit (MMU) approaching the spinning WESTAR VI satellite over Bahama Banks. The end effector of the Remote Manipulator System (RMS) controlled by Dr. Anna L. Fisher inside the space shuttle Discovery's cabin, awaits its duty at right. Gardner made a hard dock with the stinger at 6:32 a.m. (CST). Photo credit: NASA

Astronat Dale A. Gardner achieves a hard dock with the previously spinning Westar VI satellite. Gardner uses a "stinger" device to stabilize the communications satellite.

S83-40555 (15 October 1983) --- These five astronauts are in training for the STS-41B mission, scheduled early next year. On the front row are Vance D. Brand, commander; and Robert L. Gibson, pilot. Mission specialists (back row, left to right) are Robert L. Stewart, Dr. Ronald E. McNair and Bruce McCandless II. Stewart and McCandless are wearing Extravehicular Mobility Units (EMU) space suits. The STS program's second extravehicular activity (EVA) is to be performed on this flight, largely as a rehearsal for a scheduled repair visit to the Solar Maximum Satellite (SMS), on a later mission. The Manned Maneuvering Unit (MMU) will make its space debut on STS-41B.

S84-27018 (7 Feb 1984) --- Astronaut Bruce McCandless II approaches his maximum distance from the Earth-orbiting Space Shuttle Challenger in this 70mm frame photographed by his fellow crewmembers onboard the reusable vehicle. McCandless is in the midst of the first "field" tryout of the nitrogen-propelled, hand-controlled back-pack device called the manned maneuvering unit (MMU). Astronaut Robert L. Stewart got a chance to test the same unit a while later in the lengthy EVA session while the two spacewalkers were photographed and monitored by their fellow crewmembers in Challenger's cabin. Those inside were Astronauts Vance D. Brand, Robert L. Gibson and Dr. Ronald E. McNair.

CAPE CANAVERAL, Fla. -- At the Kennedy Space Center Visitor Complex in Florida, a display inside the "Space Shuttle Atlantis" facility features an extravehicular activity mobility unit -- the space suit worn by spacewalking astronauts during the shuttle program. Attached to the back is a Manned Maneuvering Unit jet pack worn by astronauts during untethered spacewalks on STS-41B and STS-41C. The new $100 million facility will include interactive exhibits that tell the story of the 30-year Space Shuttle Program and highlight the future of space exploration. The "Space Shuttle Atlantis" exhibit is scheduled to open June 29, 2013.Photo credit: NASA/Jim Grossmann

41C-52-2646 (11 April 1984) --- Astronaut James D. van Hoften and a repaired satellite are in a wide panorama recorded on film with a Linhof camera, making its initial flight aboard the Space Shuttle Challenger. Dr. van Hoften is getting in his first "field" test of the Manned Maneuvering Unit (MMU) after months of training in an underwater facility and in a simulator on Earth. The Solar Maximum Mission Satellite (SMMS), revived and almost ready for release into space once more, is docked at the Flight Support System (FSS). The Remote Manipulator System (RMS) is backdropped against the blue and white Earth at frame's edge. Outside of pictures made of the Earth from astronauts on the way to the Moon, this frame showing the planet from 285 nautical miles represents the highest orbital photography in the manned space program.

S66-33163 (May 1966) --- Rear view of the Astronaut Maneuvering Unit (AMU), worn by test subject Fred Spross, Crew Systems Division. The Gemini spacesuit, backpack and chest pack comprise the AMU, a system which is essentially a miniature manned spacecraft. The spacesuit legs are covered with Chromel R, which is a cloth woven from stainless steel fibers, used to protect the astronaut and suit from the hot exhaust thrust of the AMU backpack. Astronaut Eugene A. Cernan will wear the AMU during his Gemin-9A extravehicular activity (EVA). Photo credit: NASA

CAPE CANAVERAL, Fla. –– Hall of Fame astronaut Rick Hauk (right) welcomes one of the new members, astronaut George "Pinky" Nelson, into the U.S. Astronaut Hall of Fame. The ceremony was held at NASA's Kennedy Space Center Visitor Complex in Florida. Nelson was one of only six space shuttle astronauts to fly untethered in space using NASA's Manned Maneuvering Unit. The ceremony took place May 2. More than 20 hall of fame astronauts attended, including Scott Carpenter, Walt Cunningham, Jim Lovell and Bob Crippen. Photo credit: NASA/Jim Grossmann

S83-42893 (19 Oct 1983) ---- Astronauts George D. Nelson and James D. van Hoften, two of three STS-41C mission specialists, share an extravehicular activity (EVA) task in this simulation of a Solar Maximum Satellite (SMS) repair visit. The two are making use of the Johnson Space Center's (JSC) weightless environment training facility (WET-F). Dr. Nelson is equipped with the manned maneuvering unit (MMU) trainer and he handles the trunion pin attachment device (TPAD), a major tool to be used on the mission. The photograph was taken by Otis Imboden.

S66-33162 (May 1966) --- Test subject Fred Spross, Crew Systems Division, wears configured extravehicular spacesuit assembly and Extravehicular Life Support System chest pack. The spacesuit legs are covered with Chromel R, which is a cloth woven from stainless steel fibers, used to protect the suit and astronaut from the hot exhaust thrust of the Astronaut Maneuvering Unit backpack. The Gemini spacesuit, backpack and chest pack comprise the AMU, a system which is essentially a miniature manned spacecraft. Astronaut Eugene A. Cernan will wear the AMU during his Gemini-9A extravehicular activity (EVA). Photo credit: NASA

S66-33167 (May 1966) --- Test subject Fred Spross, Crew Systems Division, wears an Astronaut Maneuvering Unit (AMU). The Gemini spacesuit, AMU backpack, and the Extravehicular Life Support System chest pack comprises the AMU, a system which is essentially a miniature manned spacecraft. The spacesuit legs are covered with Chromel R, which is a cloth woven from stainless steel fibers, used to protect the suit and astronaut from the hot exhaust thrust of the AMU backpack. Astronaut Eugene A. Cernan will wear the AMU during his Gemini-9A extravehicular activity (EVA). Photo credit: NASA

51A-46-057 (14 November 1984) --- Astronaut Dale A. Gardner, getting his turn in the Manned Maneuvering Unit (MMU) like those used by five other astronauts this year, prepares to dock with the spinning WESTAR VI satellite. Gardner used a large tool called the Apogee Kick Motor Capture Device (ACD) to enter the nozzle of a spent WESTAR VI engine and stabilize the communications spacecraft sufficiently to capture it for return to Earth in the cargo bay of the Space Shuttle Discovery. This frame was used by the STS-51A crew at its Post-Flight Press Conference (PFPC) on November 28, 1984.

S84-27040 (7 Feb 1984) --- Some have called it NASA's first "cherry picker" in space. Others simply call it the mobile foot restraint (MFR) connected to the remote manipulator system (RMS). Astronaut Bruce McCandless II, pictured leaning out into space as his feet are anchored in the MFR, and moved around by the RMS, calls it a look of things to come. The aft portion of the Challenger, to which the RMS is connected, is seen in lower left corner. This photograph is one of a sequence showing McCandless in the device. On this same EVA, McCandless also initiated use of the manned maneuvering unit (MMU), not pictured here, a nitrogen-propelled back pack apparatus allowing for free movement in space.

CAPE CANAVERAL, Fla. –– New inductee astronaut George "Pinky" Nelson addresses the spectators at the U.S. Astronaut Hall of Fame ceremony held at NASA's Kennedy Space Center Visitor Complex in Florida. Nelson was one of only six space shuttle astronauts to fly untethered in space using NASA's Manned Maneuvering Unit. The ceremony took place May 2. More than 20 hall of fame astronauts attended, including Scott Carpenter, Walt Cunningham, Jim Lovell and Bob Crippen. Photo credit: NASA/Jim Grossmann

CAPE CANAVERAL, Fla. –– George "Pinky" Nelson (right) is introduced as one of the new members of the U.S. Astronaut Hall of Fame at NASA's Kennedy Space Center Visitor Complex in Florida. At left is hall of fame member Al Worden. Nelson was one of only four space shuttle astronauts to fly untethered in space using NASA's Manned Maneuvering Unit. The ceremony took place May 2. More than 20 hall of fame astronauts attended, including Scott Carpenter, Walt Cunningham, Jim Lovell and Bob Crippen. Photo credit: NASA/Jim Grossmann

S84-27562 (7 Feb. 1984) --- Astronaut Bruce McCandless II, one of two 41B mission specialists participating in a historical Extravehicular Activity (EVA), is a few meters away from the cabin of the Earth-orbiting space shuttle Challenger in this 70mm frame. This Extravehicular Activity (EVA) represented the first use of a nitrogen-propelled, hand-controlled device called the Manned Maneuvering Unit (MMU), which allows for much greater mobility than that afforded previous spacewalkers who had to use restrictive tethers. Robert L. Stewart later tried out the MMU McCandless is using here, and the two of them tested another similar unit two days later. Inside the spacecraft were astronauts Vance D. Brand, commander; Robert L. Gibson, pilot; and Ronald E. McNair, mission specialist. Photo credit: NASA

S84-27017 (7 Feb. 1984) --- Astronaut Bruce McCandless II, one of two 41-B mission specialist, participating in a historical Extravehicular Activity (EVA), is a few meters away from the cabin of the Earth-orbiting space shuttle Challenger in this 70mm frame. This EVA represented the first use of a nitrogen-propelled, hand-controlled device called the Manned Maneuvering Unit (MMU), which allows for much greater mobility than that afforded previous spacewalkers who had to use restrictive tethers. Robert L. Stewart, mission specialist, later tried out the MMU McCandless is using here. The two of them tested another similar unit two days later. Inside the spacecraft were astronauts Vance D. Brand, commander; Robert L. Gibson, pilot; and Ronald E. McNair, mission specialist. Photo credit: NASA

S65-19504 (28 May 1965) --- Astronaut Edward H. White II, pilot for the Gemini-Titan 4 prime crew, is pictured during an extravehicular exercise in the Building 4 laboratory at the Manned Spacecraft Center in Houston, Texas. White is controlling about the yaw (vertical) axis while translating. He stands on a Balance Extravehicular Training Aircraft which is separated from the level steel floor by a .001th-inch cushion of air. In his right hand White holds a zero-gravity integral propulsion unit which is a self-maneuvering device used by an astronaut in a zero-gravity environment. This condition is simulated in this training exercise. White's spacesuit is pressurized to create a realistic training condition. The simulated umbilical line is floated on air with the aid of eleven small air pads.

S65-19505 (28 May 1965) --- Astronaut Edward H. White II, pilot for the Gemini-Titan 4 prime crew, is pictured during an extravehicular exercise in the Building 4 laboratory at the Manned Spacecraft Center in Houston, Texas. White is controlling about the yaw (vertical) axis while translating. He stands on a Balance Extravehicular Training Aircraft which is separated from the level steel floor by a .001th-inch cushion of air. In his right hand White holds a zero-gravity integral propulsion unit which is a self-maneuvering device used by an astronaut in a zero-gravity environment. This condition is simulated in this training exercise. White's spacesuit is pressurized to create a realistic training condition. The simulated umbilical line is floated on air with the aid of eleven small air pads.

S84-27020 (7 Feb 1984) --- A fixed camera on astronaut Bruce McCandless II's helmet recorded this rare scene of the Space Shuttle Challenger some 50 to 60 meters away during a history-making extravehicular activity (EVA), February 7, 1984. The Shuttle Pallet Satellite (SPAS-01A) is configured mid-cargo bay. Astronaut Robert L. Stewart, standing beneath the Remote Manipulator System (RMS) arm, later donned the same Manned Maneuvering Unit (MMU) which afforded McCandless the freedom of movement to record this image. Also visible in the cargo bay are the support stations for the two MMU back-packs, the sunshields for the Palapa B and Westar VI Satellites, KU-Band antenna and a number of Getaway Special (GAS) canisters.

CAPE CANAVERAL, Fla. –– The three newest inductees into the U.S. Astronaut Hall of Fame proudly join current members after the induction ceremony held at NASA's Kennedy Space Center Visitor Complex in Florida. In front, from left, are George "Pinky" Nelson, who was one of only six space shuttle astronauts to fly untethered in space using NASA's Manned Maneuvering Unit; William Shepherd, who was commander of the first crew to live aboard the International Space Station; and James Wetherbee, who was commander of the longest-docked shuttle-Mir mission. The ceremony was held at NASA's Kennedy Space Center Visitor Complex in Florida. The ceremony took place May 2. More than 20 hall of fame astronauts attended, including Scott Carpenter, Walt Cunningham, Jim Lovell and Bob Crippen. Photo credit: NASA/Jim Grossmann

CAPE CANAVERAL, Fla. –– The three newest inductees into the U.S. Astronaut Hall of Fame congratulate each other after receiving their medals. From left are George "Pinky" Nelson, who was one of only six space shuttle astronauts to fly untethered in space using NASA's Manned Maneuvering Unit; William Shepherd, who was commander of the first crew to live aboard the International Space Station; and James Wetherbee, who was commander of the longest-docked shuttle-Mir mission. The ceremony was held at NASA's Kennedy Space Center Visitor Complex in Florida. The ceremony took place May 2. More than 20 hall of fame astronauts attended, including Scott Carpenter, Walt Cunningham, Jim Lovell and Bob Crippen. Photo credit: NASA/Jim Grossmann

CAPE CANAVERAL, Fla. –– The three newest inductees into the U.S. Astronaut Hall of Fame share the stage after receiving their medals. From left are George "Pinky" Nelson, who was one of only six space shuttle astronauts to fly untethered in space using NASA's Manned Maneuvering Unit; William Shepherd, who was commander of the first crew to live aboard the International Space Station; and James Wetherbee, who was commander of the longest-docked shuttle-Mir mission. The ceremony was held at NASA's Kennedy Space Center Visitor Complex in Florida. The ceremony took place May 2. More than 20 hall of fame astronauts attended, including Scott Carpenter, Walt Cunningham, Jim Lovell and Bob Crippen. Photo credit: NASA/Jim Grossmann

Test subject wearing jet-shoe apparatus and resting in sling support. The cables are not attached. From A.W. Vogeley, "Piloted Space-Flight Simulation at Langley Research Center," Paper presented at the American Society of Mechanical Engineers, 1966 Winter Meeting, New York, NY, November 27 - December 1, 1966. "As mentioned previously, Langley is conducting in-house and contract studies of extra-vehicular activities wherein zero gravity is simulated by the water-immersion technique. ... Water immersion is a very useful technique where motions are slow. When more rapid motion is required, as in studying one-man propulsion systems, other approaches are required. For these studies Langley has been using the RDS [Rendezvous Docking Simulator] in a manner similar to the LLRF [Lunar Landing Research Facility] technique. The test subjects are suspended in a sling support from a single RDS cable. As they translate about, the RDS tracks them, keeping the cable vertical. The test subjects operate in an effectively zero g environment in the horizontal plane. Tracking was originally done visually using closed-circuit TV, but recently a fast-response servo system using cable angle sensors has provided better operation. Some results of tests where subjects moved about merely by jumping and also where propulsion in the form of simple "jet-shoes" was provided are given in reference 20. Both methods, within limits, appear feasible. Full six-degree-of-freedom equipment for studies of more sophisticated one-man propulsion systems is now being procured. Called OMPRA (One-Man Propulsion Research Apparatus), the device will provide a gimbal system for rotational freedom, a quick response vertical servo for this translational freedom that is not now feasible with the RDS, and a versatile maneuvering unit."

In February 1980, a satellite called Solar Maximum Mission Spacecraft, or Solar Max, was launched into Earth's orbit. Its primary objective was to provide a detailed study of solar flares, active regions on the Sun's surface, sunspots, and other solar activities. Additionally, it was to measure the total output of radiation from the Sun. Not much was known about solar activity at that time except for a slight knowledge of solar flares. After its launch, Solar Max fulfilled everyone's expectations. However, after a year in orbit, Solar Max's Altitude Control System malfunctioned, preventing the precise pointing of instruments at the Sun. NASA scientists were disappointed at the lost data, but not altogether dismayed because Solar Max had been designed for Space Shuttle retrievability enabling repair of the satellite. On April 6, 1984, Space Shuttle Challenger (STS-41C), Commanded by astronaut Robert L. Crippen and piloted by Francis R. Scobee, launched on a historic voyage. This voyage initiated a series of firsts for NASA; the first satellite retrieval, the first service use of a new space system called the Marned Maneuvering Unit (MMU), the first in-orbit repair, the first use of the Remote Manipulator System (RMS), and the Space Shuttle Challenger's first space flight. The mission was successful in retrieving Solar Max. Mission Specialist Dr. George D. Nelson, using the MMU, left the orbiter's cargo bay and rendezvoused with Solar Max. After attaching himself to the satellite, he awaited the orbiter to maneuver itself nearby. Using the RMS, Solar Max was captured and docked in the cargo bay while Dr. Nelson replaced the altitude control system and the coronagraph/polarimeter electronics box. After the repairs were completed, Solar Max was redeposited in orbit with the assistance of the RMS. Prior to the April 1984 launch, countless man-hours were spent preparing for this mission. The crew of Challenger spent months at Marshall Space Flight Center's (MSFC) Neutral Buoyancy Simulator (NBS) practicing retrieval maneuvers, piloting the MMU, and training on equipment so they could make the needed repairs to Solar Max. Pictured is Dr. Nelson performing a replacement task on the Solar Max mock-up in the NBS.

In February 1980, a satellite called Solar Maximum Mission Spacecraft, or Solar Max, was launched into Earth's orbit. Its primary objective was to provide a detailed study of solar flares,active regions on the Sun's surface, sunspots, and other solar activities. Additionally, it was to measure the total output of radiation from the Sun. Not much was known about solar activity at that time except for a slight knowledge of solar flares. After its launch, Solar Max fulfilled everyone's expectations. However, after a year in orbit, Solar Max's Altitude Control System malfunctioned, preventing the precise pointing of instruments at the Sun. NASA scientists were disappointed at the lost data, but not altogether dismayed because Solar Max had been designed for Space Shuttle retrievability enabling the repair of the satellite. On April 6, 1984, Space Shuttle Challenger (STS-41C), Commanded by astronaut Robert L. Crippen and piloted by Francis R. Scobee, launched on a historic voyage. This voyage initiated a series of firsts for NASA; the first satellite retrieval, the first service use of a new space system called the Marned Maneuvering Unit (MMU), the first in-orbit repair, the first use of the Remote Manipulator System (RMS), and the Space Shuttle Challenger's first space flight. The mission was successful in retrieving Solar Max. Mission Specialist Dr. George D. Nelson, using the MMU, left the orbiter's cargo bay and rendezvoused with Solar Max. After attaching himself to the satellite, he awaited the orbiter to maneuver itself nearby. Using the RMS, Solar Max was captured and docked in the cargo bay while Dr. Nelson replaced the altitude control system and the coronagraph/polarimeter electronics box. After the repairs were completed, Solar Max was redeposited in orbit with the assistance of the RMS. Prior to the April 1984 launch, countless man-hours were spent preparing for this mission. The crew of Challenger spent months at Marshall Space Flight Center's (MSFC) Neutral Buoyancy Simulator (NBS) practicing retrieval maneuvers, piloting the MMU, and training on equipment so they could make the needed repairs to Solar Max. Pictured is Dr. Nelson performing a replacement task on the Solar Max mock-up in the NBS.

In February 1980, a satellite called Solar Maximum Mission Spacecraft, or Solar Max, was launched into Earth's orbit. Its primary objective was to provide a detailed study of solar flares, active regions on the Sun's surface, sunspots, and other solar activities. Additionally, it was to measure the total output of radiation from the Sun. Not much was known about solar activity at that time except for a slight knowledge of solar flares. After its launch, Solar Max fulfilled everyone's expectations. However, after a year in orbit, Solar Max's Altitude Control System malfunctioned, preventing the precise pointing of instruments at the Sun. NASA scientists were disappointed at the lost data, but not altogether dismayed because Solar Max had been designed for Space Shuttle retrievability enabling the repair of the satellite. On April 6, 1984, Space Shuttle Challenger (STS-41C), Commanded by astronaut Robert L. Crippen and piloted by Francis R. Scobee, launched on a historic voyage. This voyage initiated a series of firsts for NASA; the first satellite retrieval, the first service use of a new space system called the Marned Maneuvering Unit (MMU), the first in-orbit repair, the first use of the Remote Manipulator System (RMS), and the Space Shuttle Challenger's first space flight. The mission was successful in retrieving Solar Max. Mission Specialist Dr. George D. Nelson, using the MMU, left the orbiter's cargo bay and rendezvoused with Solar Max. After attaching himself to the satellite, he awaited the orbiter to maneuver itself nearby. Using the RMS, Solar Max was captured and docked in the cargo bay while Dr. Nelson replaced the altitude control system and the coronagraph/polarimeter electronics box. After the repairs were completed, Solar Max was redeposited in orbit with the assistance of the RMS. Prior to the April 1984 launch, countless man-hours were spent preparing for this mission. The crew of Challenger spent months at Marshall Space Flight Center's (MSFC) Neutral Buoyancy Simulator (NBS) practicing retrieval maneuvers, piloting the MMU, and training on equipment so they could make the needed repairs to Solar Max. Pictured are crew members training for repair tasks.

In February 1980, a satellite called Solar Maximum Mission Spacecraft, or Solar Max, was launched into Earth's orbit. Its primary objective was to provide a detailed study of solar flares, active regions on the Sun's surface, sunspots, and other solar activities. Additionally, it was to measure the total output of radiation from the Sun. Not much was known about solar activity at that time except for a slight knowledge of solar flares. After its launch, Solar Max fulfilled everyone's expectations. However, after a year in orbit, Solar Max's Altitude Control System malfunctioned, preventing the precise pointing of instruments at the Sun. NASA scientists were disappointed at the lost data, but not altogether dismayed because Solar Max had been designed for Space Shuttle retrievability enabling the repair of the satellite. On April 6, 1984, Space Shuttle Challenger (STS-41C), Commanded by astronaut Robert L. Crippen and piloted by Francis R. Scobee, launched on a historic voyage. This voyage initiated a series of firsts for NASA; the first satellite retrieval, the first service use of a new space system called the Marned Maneuvering Unit (MMU), the first in-orbit repair, the first use of the Remote Manipulator System (RMS), and the Space Shuttle Challenger's first space flight. The mission was successful in retrieving Solar Max. Mission Specialist Dr. George D. Nelson, using the MMU, left the orbiter's cargo bay and rendezvoused with Solar Max. After attaching himself to the satellite, he awaited the orbiter to maneuver itself nearby. Using the RMS, Solar Max was captured and docked in the cargo bay while Dr. Nelson replaced the altitude control system and the coronagraph/polarimeter electronics box. After the repairs were completed, Solar Max was redeposited in orbit with the assistance of the RMS. Prior to the April 1984 launch, countless man-hours were spent preparing for this mission. The crew of Challenger spent months at Marshall Space Flight Center's (MSFC) Neutral Buoyancy Simulator (NBS) practicing retrieval maneuvers, piloting the MMU, and training on equipment so they could make the needed repairs to Solar Max. Pictured are crew members training on repair tasks.

In February 1980, a satellite called Solar Maximum Mission Spacecraft, or Solar Max, was launched into Earth's orbit. Its primary objective was to provide a detailed study of solar flares, active regions on the Sun's surface, sunspots, and other solar activities. Additionally, it was to measure the total output of radiation from the Sun. Not much was known about solar activity at that time except for a slight knowledge of solar flares. After its launch, Solar Max fulfilled everyone's expectations. However, after a year in orbit, Solar Max's Altitude Control System malfunctioned, preventing the precise pointing of instruments at the Sun. NASA scientists were disappointed at the lost data, but not altogether dismayed because Solar Max had been designed for Space Shuttle retrievability enabling the repair of the satellite. On April 6, 1984, Space Shuttle Challenger (STS-41C), Commanded by astronaut Robert L. Crippen and piloted by Francis R. Scobee, launched on a historic voyage. This voyage initiated a series of firsts for NASA; the first satellite retrieval, the first service use of a new space system called the Marned Maneuvering Unit (MMU), the first in-orbit repair, the first use of the Remote Manipulator System (RMS), and the Space Shuttle Challenger's first space flight. The mission was successful in retrieving Solar Max. Mission Specialist Dr. George D. Nelson, using the MMU, left the orbiter's cargo bay and rendezvoused with Solar Max. After attaching himself to the satellite, he awaited the orbiter to maneuver itself nearby. Using the RMS, Solar Max was captured and docked in the cargo bay while Dr. Nelson replaced the altitude control system and the coronagraph/polarimeter electronics box. After the repairs were completed, Solar Max was redeposited in orbit with the assistance of the RMS. Prior to the April 1984 launch, countless man-hours were spent preparing for this mission. The crew of Challenger spent months at Marshall Space Flight Center's (MSFC) Neutral Buoyancy Simulator (NBS) practicing retrieval maneuvers, piloting the MMU, and training on equipment so they could make the needed repairs to Solar Max. Pictured is Dr. Nelson performing a replacement task on the Solar Max mock-up in the NBS.

In February 1980, a satellite called Solar Maximum Mission Spacecraft, or Solar Max, was launched into Earth's orbit. Its primary objective was to provide a detailed study of solar flares,active regions on the Sun's surface, sunspots, and other solar activities. Additionally, it was to measure the total output of radiation from the Sun. Not much was known about solar activity at that time except for a slight knowledge of solar flares. After its launch, Solar Max fulfilled everyone's expectations. However, after a year in orbit, Solar Max's Altitude Control System malfunctioned, preventing the precise pointing of instruments at the Sun. NASA scientists were disappointed at the lost data, but not altogether dismayed because Solar Max had been designed for Space Shuttle retrievability, enabling repair to the satellite. On April 6, 1984, Space Shuttle Challenger (STS-41C), Commanded by astronaut Robert L. Crippen and piloted by Francis R. Scobee, launched on a historic voyage. This voyage initiated a series of firsts for NASA; the first satellite retrieval, the first service use of a new space system called the Marned Maneuvering Unit (MMU), the first in-orbit repair, the first use of the Remote Manipulator System (RMS), and the Space Shuttle Challenger's first space flight. The mission was successful in retrieving Solar Max. Mission Specialist Dr. George D. Nelson, using the MMU, left the orbiter's cargo bay and rendezvoused with Solar Max. After attaching himself to the satellite, he awaited the orbiter to maneuver itself nearby. Using the RMS, Solar Max was captured and docked in the cargo bay while Dr. Nelson replaced the altitude control system and the coronagraph/polarimeter electronics box. After the repairs were completed, Solar Max was redeposited in orbit with the assistance of the RMS. Prior to the April 1984 launch, countless man-hours were spent preparing for this mission. The crew of Challenger spent months at Marshall Space Flight Center's (MSFC) Neutral Buoyancy Simulator (NBS) practicing retrieval maneuvers, piloting the MMU, and training on equipment so they could make the needed repairs to Solar Max. Pictured is Dr. Nelson performing a replacement task on the Solar Max mock-up in the NBS.

S83-45520 (December 1983) --- The space shuttle Challenger, making its fourth spaceflight, highlights the 41B insignia. The reusable vehicle is flanked in the oval by an illustration of another PAM-D assisted satellite deployment; and astronaut making the first non-tethered extravehicular activity (EVA); and eleven stars. The crew member at right is equipped with the manned maneuvering unit (MMU), a debuting backpack/motor apparatus allowing for much greater freedom of movement than that experienced by any previous space travelers performing EVA. Surnames of the five astronaut crew members balance the Robert McCall artwork. They are Vance D. Brand, Robert L. Stewart, Bruce McCandless II, Ronald E. McNair, Robert L. Gibson. The flight is scheduled for a launch in early 1984. The NASA insignia design for space shuttle flights is reserved for use by the astronauts and for other official use as the NASA Administrator may authorize. Public availability has been approved only in the forms of illustrations by the various news media. When and if there is any change in this policy, which is not anticipated, the change will be publicly announced. Photo credit: NASA