Dr. Laurie Leshin, NASA Deputy Associate Administrator Exploration Systems Mission Directortorate, second from right, speaks as Dr. Waleed Abdalati, NASA Chief Scientist, right, Dr. Robert Braun, NASA Chief Technologist, and Leland Melvin, Assoicate Administrator for NASA Education, far left, at the NASA Future Forum held at the Riggs Alumni Center on the campus of the University of Maryland, Thursday, Aug. 11, 2011 in College Park, Md. Photo Credit: (NASA/Paul E. Alers)

William Bo-Ricki, Kepler principal investigator at NASA's Ames Research Center, speaks during a press conference, Thursday, Aug. 6, 2009, at NASA Headquarters in Washington about the scientific observations coming from the Kepler spacecraft that was launched this past March. Kepler is NASA's first mission that is capable of discovering earth-sized planets in the habitable zones of stars like our Sun. Photo Credit: (NASA/Paul E. Alers)

NASA astronaut Mike Massimino, left, and Sesame Street's Elmo speak at the STS-135 Tweetup, Thursday, July 7, 2011, at Kennedy Space Center in Cape Canaveral, Fla. Elmo asked the astronauts questions about living and working in space. About 150 NASA Twitter followers attended the event. The STS-135 mission will be NASA's last space shuttle launch. Photo Credit: (NASA/Paul E. Alers)

Madhulika Guhathakurta, SDO Program Scientist, speaks during a briefing to discuss the upcoming launch of NASA's Solar Dynamic Observatory, or SDO, Thursday, Jan. 21, 2010, at NASA Headquarters in Washington. The mission is to study the Sun and its dynamic behavior. Photo Credit: (NASA/Paul E. Alers)

Dr. Elizabeth M. Robinson, nominee for Chief Financial Officer for NASA, center, answers questions during her confirmation hearing in front of the Senate Committee on Commerce, Science and Transportation, Thursday, Oct. 15, 2009, on Capitol Hill in Washington. Robinson is flanked by Dr. Patrick Gallagher, nominee to be Assistant Secretary of the Transportation Security Administration at the U.S. Department of Commerce, far left, and Paul K. Martin, nominee to be Inspector General at NASA. Photo Credit: (NASA/Paul E. Alers)

A Shorty Award is seen Wednesday, March 30, 2011 at NASA Headquarters in Washington. The award was presented to NASA astronaut Doug Wheelock for an image of the moon he took and posted to his Twitter account, @Astro_Wheels, while living aboard the International Space Station last year. The awards ceremony was held at the TimesCenter in New York City on Monday, March 28. Photo Credit: (NASA/Paul E. Alers)

NASA chief historian Steven Dick, seated left, shares a laugh with panelists John Logsdon, Roger Launius, Michael Neufeld, Cristina Guidi and Craig Nelson, at an Apollo History and Legacy roundtable discussion, Thursday, July 16, 2009, at NASA Headquarters in Washington. Photo Credit: (NASA/Paul E. Alers)

NASA Administrator Charles F. Bolden appears in front of the U.S. House of Representatives Committee on Science and Technology to discuss the President's FY 2011 budget request, Thursday, Feb. 25, 2010, on Capitol Hill in Washington. Photo Credit: (NASA/Paul E. Alers)

A student from the Maryland School For the Blind explores an object while learning about Meteorites, Asteroids and Comets during NASA's Disability Mentoring Day, Thursday, April 7, 2011, at NASA Headquarters in Washignton. Photo Credit: (NASA/Paul E. Alers)

STS-125 astronaut John Grunsfeld speaks during a press briefing at the new "Moving Beyond Earth," a new exhibition at the National Air and Space Museum in Washingon, Wednesday, Nov. 18, 2009. Moving Beyond Earth is an immersive exhibition that places visitors “in orbit” in the shuttle and space-station era to explore recent human spaceflight and future possibilities. Photo Credit: (NASA/Paul E. Alers)

Dr. Steve Squyres, from Cornell University, talks during a Mars Program Update where prominent scientists discussed evidence of water on Mars, current Program status, including the 7th Anniversary of the Mars rovers and the upcoming Mars Science Laboratory mission and previewing exciting discoveries to come, Thursday, Jan. 13, 2011, at the Smithsonian National Air and Space Museum in Washington. Photo Credit: (NASA/Paul E. Alers)

NASA Administrator Charles Bolden, foreground, speaks with Howard University students after he and and U.S. Environmental Protection Agency (EPA) Administrator Lisa P. Jackson, right, signed a Memorandum of Agreement (MOA) to promote collaboration between the two agencies for cooperation in environmental and Earth sciences and environmental management applications at the Howard University Middle School of Mathematics and Science, Monday, April 26, 2010, in Washington. Photo Credit: (NASA/Paul E. Alers)

Guests view space shuttle Endeavour (STS-134) as it launches skyward from the balcony of the Operations Support Building II (OSB-II), Monday, May 16, 2011, at Kennedy Space Center in Cape Canaveral, Fla. During the 16-day mission, Endeavour, with Commander Mark Kelly, Pilot Gregory H. Johnson, Mission Specialists Michael Fincke, Greg Chamitoff, Andrew Feustel and European Space Agency astronaut Robert Vittori will deliver the Alpha Magnetic Spectrometer (AMS) and spare parts including two S-band communications antennas, a high-pressure gas tank and additional spare parts for Dextre. Photo Credit: (NASA/Paul E. Alers)

Simone Tanelli, a researcher from the Jet Propulsion Laboratory, talks about the Airbrorne Precipitation Radar (APR-2) aboard the NASA DC-8 aircraft, Monday, Aug.16, 2010, at Fort Lauderdale Hollywood International Airport in Fort Lauderdale, Fla. The APR-2, a dual frequency weather radar, is just one of the experiments supporting the Genesis and Rapid Intensification Processes (GRIP) mission, a NASA Earth science field experiment that is being conducted to better understand how tropical storms form and develop into major hurricanes. Photo Credit: (NASA/Paul E. Alers)

Asher Gendelman, a director of technology at Zephyr Technology, holds up chest belt as he speaks about technology investments and their benefits during a panel discussion at the 2011 NASA Future Forum held at the Riggs Alumni Center on the campus of the University of Maryland, Thursday, Aug. 11, 2011, in College Park, Md. Photo Credit: (NASA/Paul E. Alers)

Paul K. Martin, nominee for Inspector General for NASA, answers questions during his confirmation hearing in front of the Senate Committee on Commerce, Science and Transportation, Thursday, Oct. 15, 2009, on Capitol Hill in Washington. Photo Credit: (NASA/Paul E. Alers)

John Logsdon, Charles A. Lindbergh chair in aerospace history at the Smithsonianan, left, speaks as other panelists look on during an Apollo History and Legacy roundtable discussion, Thursday, July 16, 2009, at NASA Headquarters in Washington. Photo Credit: (NASA/Paul E. Alers)

NASA Adminiistrator Charles F. Bolden, left, and Jean-Jacques Dordain, Director General of the European Space Agency (ESA), shake hands, Friday, Sept. 11, 2009, after signing a Space Transportation Memorandum of Understanding (MOU) at NASA Headquarters in Washington. Photo Credit: (NASA/Paul E. Alers)

Dr. Anita Cochran, Assistant Director, McDonald Observatory at the University of Texas-Austin, speaks during a symposium commemorating a quarter-century of comet discoveries, Friday, Sept. 10, 2010, in the Knight studio at the Newseum in Washington. The International Sun-Earth Explorer-3 (ISEE-3) spacecraft flew past the comet Giacobini-Zinner on Sept. 11, 1985 which established a foundation of discoveries that continue today. Photo Credit: (NASA/Paul E. Alers)

NASA Administrator Charles Boldenl left, speaks as Deputy Administrator Lori Garver looks on at the 2009 NASA Executive Summit, Tuesday, Oct. 6, 2009, at the Ronald Reagan Building in Washington. (Photo Credit: (NASA/Paul E. Alers)

Michael A'Hearn, EPOXI Principal Investigator, University of Maryland, holds a plastic bottle containing ice to illustrate a point during a press conference, Thursday, Nov. 18, 2010, at NASA Headquarters in Washington. The press conference was held to discuss the Nov. 4 successful flyby of Comet Hartley 2 by NASA's EPOXI Mission Spacecraft. Images from the flyby provided scientists the most extensive observations of a comet in history. Photo Credit: (NASA/Paul E. Alers)

Cloud formations are seen through the window of NASA DC-8 aircraft during a flight, Tuesday, Aug. 17, 2010, over the Gulf of Mexico where researchers were studying weather patterns as part of trhe Genesis and Rapid Intensification Processes (GRIP) experiment, a NASA Earth science field experiment in 2010 that is being conducted to better understand how tropical storms form and develop into major hurricanes. Photo Credit: (NASA/Paul E. Alers)

Jon Cowart @Rocky_Sci, orbiter engineering manager, Space Shuttle Program, interacts with Tweetup participant, Jen Vargas, @jenvargus, as he speaks to participants at the two-day STS-132 Launch Tweetup at Kennedy Space Center, Thursday, May 13, 2010, in Cape Canaveral, Fla. NASA Twitter followers in attendance will have the opportunity to take a tour of NASA's Kennedy Space Center, view the space shuttle launch and speak with shuttle technicians, engineers, astronauts and managers. Photo Credit: (NASA/Paul E. Alers)

Alan Boss, an astrophyscist at the Carnegie Institution at the Department of Terrestrial Magnetism speaks during a press conference, Thursday, Aug. 6, 2009, at NASA Headquarters in Washington about the scientific observations coming from the Kepler spacecraft that was launched this past March. Kepler is NASA's first mission that is capable of discovering earth-sized planets in the habitable zones of stars like our Sun. Photo Credit: (NASA/Paul E. Alers)

Retired Navy Captain and commander of Apollo 17 Eugene Cernan, center, is flanked by Apollo 11 Commander Neil Armstrong, left, and A. Thomas Young, as he testifies during a hearing before the House Science and Technology Committee, Tuesday, May 26, 2010, at the Rayburn House office building on Capitol Hill in Washington. The hearing was to review proposed human spaceflight plan by NASA. Photo Credit: (NASA/Paul E. Alers)

STS-127 Commander Mark Polansky speaks to White House interns at the Eisenhower Executiive Office Building in Washington, Thursday, Sept. 24, 2009. Photo Credit: (NASA/Paul E. Alers)

NASA Administrator Charles Bolden, left, holds a box of spiders as MathScience Innovation Center Instructor Rhonda Hawley describes them during a visit to the "Spider Room" at the center, Friday, Jan. 28. 2011, at the center in Richmond, Va. Earlier, Bolden spoke to students from Albert Hill Middle School, where he highlighted the importance of science, technology, engineering and math, or STEM, as he shared his life experiences with the students. (Photo Credit:NASA/Paul E. Alers)

Dr. James L. Green, Director of Planetary Science at NASA, right, speaks with Dr. Robert Farquar, an executive for space exploration at KinetX Inc., during a symposium commemorating a quarter-century of comet discoveries, Friday, Sept. 10, 2010, in the Knight studio at the Newseum in Washington. The International Sun-Earth Explorer-3 (ISEE-3) spacecraft flew past the comet Giacobini-Zinner on Sept. 11, 1985 which established a foundation of discoveries that continue today. Photo Credit: (NASA/Paul E. Alers)

NASA Administrator Charles F. Bolden speaks to students during a visit to Davis Elementary School, Friday, Sept. 11, 2009, in Washington. Bolden spent time with approximately 120 students in third, fourth and fifth grade talking about science, technology, mathematics and engineering as part of the National Day of Service and Remembrance. Photo Credit: (NASA/Paul E. Alers)

Dr. Edward Crawley, Ford Professor of Engineering at MIT and co-chair, NASA Exploration Technology Development Program Review Committee speaks during the final meeting of the Human Space Flight Review Committee, Wednesday, Aug. 12, 2009, in Washington. Photo Credit: (NASA/Paul E. Alers)

STS-128 mission specialist Jose Hernandez, left, makes a point while talking to students during an event at the U.S. Department of Education, Thursday, Nov. 5, 2009, in Washington as fellow STS-128 crew members, Patrick Forrester and Christer Fuglesang, of the European Space Agency, right, look on. NASA Administrator Charles Bolden and Secretary of Education Arne Duncan hosted Washington area middle and high school students Thursday for a live discussion with astronauts aboard the International Space Station. The event was part of the 10th annual celebration of International Education Week. Photo Credit: (NASA/Paul E. Alers)

STS-129 Mission Specialist Leland Melvin speaks to a class room of students at the Howard University Middle School of Math and Science, Tuesday, Jan. 12, 2010, on the campus of Howard University in Washington. Photo Credit: (NASA/Paul E. Alers)

Charles Miller talks during a media briefing to discuss the upcoming Orbiting Carbon Observatory mission, the first NASA spacecraft dedicated to studying carbon dioxide, Thursday, Jan. 29, 2009, at NASA Headquarters in Washington. Photo Credit: (NASA/Paul E. Alers)

Astronauts Tracy Caldwell Dyson, flight engineer on Expeditions 23 and 24, left, and Doug Wheelock, Expedition 24 flight engineer and commander of Expedition 25, discuss their mission to the International Space Station during a visit to NASA Headquarters in Washington, Wednesday, March 16, 2011. (NASA/Paul E. Alers)

Dr. Stephen Hawking, a professor of mathematics at the University of Cambridge, left, and his daughter Lucy Hawking talk about their co-authored children's book "George's Secret Key to the Universe" Monday, April 21, 2008, at George Washington University's Morton Auditorium in Washington. Stephen Hawking also delivered a speech entitled "Why we should go into space" during a lecture that is part of a series honoring NASA's 50th Anniversary, Photo Credit: (NASA/Paul. E. Alers)

Jessica Sunshine, EPOXI Deputy Principal Investigator, University of Maryland, far right, discusses imagery sent back from the EPOXI Mission spacecraft during a press conference, Thursday, Nov. 18, 2010, at NASA Headquarters in Washington. The press conference was held to discuss the Nov. 4 successful flyby of Comet Hartley 2 by NASA's EPOXI Mission Spacecraft. Images from the flyby provided scientists the most extensive observations of a comet in history. Photo Credit: (NASA/Paul E. Alers)

Members of the Human Space Flight Review Committee from left, Jeffrey Greason, Dr. Christopher Chyba, Dr. Leroy Chiao, Dr. Sally Ride, Norman Augustine (chair), Philip McAllister, Dr. Edward Crawley, Dr. Wanda Austin, and Bhodan Bejmuk review their notes prior to the start of a public meeting, Wednesday, Aug. 12, 2009, in Washington. Photo Credit: (NASA/Paul E. Alers)

NASA Deputy Administrator Lori Garver, right, along with Assistant Administrator for Legislative and Intergovernmental Affairs L. Seth Statler, meets with STS-128 astronauts Patrick Forrester, left, Jose Hernandez and Christer Fugelsang, of the European Space Agency, at NASA Headquarters, Tuesday, Nov. 3, 2009, in Washington. Photo Credit: (NASA/Paul E. Alers)

STS-129 Mission Specialist Leland Melvin speaks to students at the Howard University Middle School of Math and Science, Tuesday, Jan. 12, 2010, on the campus of Howard University in Washington. Photo Credit: (NASA/Paul E. Alers)

Astronaut James Lovell (Apollo 8 Apollo 13) gestures during the 40th anniversary of the Apollo 11 mission and the walk on the moon press conference, Monday, July 20, 2009, at NASA Headquarters in Washington. Photo Credit: (NASA/Paul E. Alers)

NASA Social participants are reflected in the sunglasses of former NASA astronaut Garrett Reisman, now a senior engineer working on astronaut safety and mission assurance for Space Exploration Technologies, or SpaceX, as he speaks with them, Friday, May 18, 2012, at the launch complex where the company's Falcon 9 rocket is set to launch early Friday morning at Cape Canaveral Air Force Station in Cape Canaveral, Fla. Photo Credit: (NASA/Paul E. Alers)

Canadian Space Agency astronaut Julie Payette, a mission specialist on STS-127, at podium, speaks to White House interns at the Eisenhower Executiive Office Building in Washington, Thursday, Sept. 24, 2009. Seated from left are crew members Christopher Cassidy, David Wolf, Mark Polansky, Douglas Hurley and Thomas Marshburn. Photo Credit: (NASA/Paul E. Alers)

Dr. Stephen Hawking, a professor of mathematics at the University of Cambridge, delivers a speech entitled "Why we should go into space" during a lecture that is part of a series honoring NASA's 50th Anniversary, Monday, April 21, 2008, at George Washington University's Morton Auditorium in Washington. Photo Credit: (NASA/Paul. E. Alers)

Colin Dundas, a research geologist with the U.S. Geological Survey, speaks during a briefing, Thursday, Aug. 4, 2011, at NASA Headquarters in Washington. Observations from NASA's Mars Reconnaissance Orbiter (MRO) have revealed possible flowing water during the warmest months on Mars. Dark, finger-like features appear and extend down some Martian slopes during late spring through summer, fade in winter, and return during the next spring. Repeated observations have tracked the seasonal changes in these recurring features on several steep slopes in the middle latitudes of Mars' southern hemisphere. Photo Credit: (NASA/Paul E. Alers)

NASA astronaut TJ Creamer talks about his experience in space during a "Tweetup" at NASA Headquarters, Thursday, July 29, 2010, in Washington. Creamer, who spent 161 days living aboard the International Space Station as part of the Expedition 22/23 crew, set up the orbiting outpost's live Internet connection and posted updates about the mission to his Twitter account, sending the first live tweet from orbit. Photo Credit: (NASA/Paul E. Alers)

Dr. Stephen Hawking, a professor of mathematics at the University of Cambridge, delivers a speech entitled "Why we should go into space" during a lecture that is part of a series honoring NASA's 50th Anniversary, Monday, April 21, 2008, at George Washington University's Morton Auditorium in Washington. Photo Credit: (NASA/Paul. E. Alers)

President Barack Obama, center, back to camera, shakes hands with NASA Administrator Charles Bolden, right, as U.S. Sen. Bill Nelson, D-Fla., looks on prior to Obama's speech outlining the bold new course the administration is charting to maintain U.S. leadership in human space flight at the NASA Kennedy Space Center in Cape Canaveral, Fla. on Thursday, April 15, 2010. Photo Credit: (NASA/Paul E. Alers)

Pete Schultz, EPOXI scientist from Brown University, makes a point during a press conference, Thursday, Nov. 18, 2010, at NASA Headquarters in Washington. The press conference was held to discuss the Nov. 4 successful flyby of Comet Hartley 2 by NASA's EPOXI Mission Spacecraft. Images from the flyby provided scientists the most extensive observations of a comet in history. Photo Credit: (NASA/Paul E. Alers)

STS-129 crew members from left, Robert Satcher, Randy Bresnik, Mike Foreman, Barry Wilmore, Commander Charles Hobaugh and Leland Melvin pose with a group of White House Fellows at NASA Headquarters in Washington, Monday, Jan. 11, 2010. Photo Credit: (NASA/Paul E. Alers)

NASA Administrator Charles Bolden, left, speaks with U.S. Sens. Barbara Mikulski, D-Md., center, and Kay Bailey Hutchison, R-Texas, right, prior to his testimony in front of the Senate Appropriations Committee, Monday, April 11, 2011, at the Dirksen Senate Office Building on Capitol Hill in Washington. Photo Credit: (NASA/Paul E. Alers)

Students from the Maryland School for the Blind participate in Disability Mentoring Day, Thursday, April 7, 2011, at NASA Headquarters in Washington. Photo Credit (NASA/Paul E. Alers)

STS-129 Mission Specialist Randy Bresnick, second from right, answers a question from the audience as fellow crew members look on, Monday, Jan. 11, 2010, during a presentation to staff and middle school students from the Congressional Schools of Virginia at NASA Headquarters in Washington. Photo Credit: (NASA/Paul E. Alers)

Maryland School for the Blind students Andrea Washington, right, reacts to fellow student Nino Jacobs, left, after he donned a Space suit during a visit to NASA Headquarters in Washington, Thursday, Oct. 29, 2009. Seven students from the Maryland School for the Blind visited NASA and participated in activities to learn about NASA'smission, functions, and careers. Student Kuassi Kouhiko is in the background. Photo Credit: (NASA/Paul E. Alers)

Debra Fischer, a professor of Astronomy at Yale University, speaks during a news conference, Wednesday, Feb. 2, 2010, at NASA Headquarters in Washington. Scientists using NASA's Kepler, a space telescope, recently discovered six planets made of a mix of rock and gases orbiting a single sun-like star, known as Kepler-11, which is located approximately 2,000 light years from Earth. Photo Credit: (NASA/Paul E. Alers)

Tim Larson, EPOXI Project Manager from the Jet Propulsion Laboratory in Pasadena, Calif., speaks during a press conference, Thursday, Nov. 18, 2010, at NASA Headquarters in Washington. The press conference was held to discuss the Nov. 4 successful flyby of Comet Hartley 2 by NASA's EPOXI Mission Spacecraft. Images from the flyby provided scientists the most extensive observations of a comet in history. Photo Credit: (NASA/Paul E. Alers)

Astronauts Tracy Caldwell Dyson, flight engineer on Expeditions 23 and 24, left, and Doug Wheelock, Expedition 24 flight engineer and commander of Expedition 25, discuss their mission to the International Space Station during a visit to NASA Headquarters in Washington, Wednesday, March 16, 2011. (NASA/Paul E. Alers)

NASA Headquarters Center Director Chris Jedrey, right, welcomes students from the Maryland School for the Blind to a visit to NASA Headquarters in Washington, Thursday, Oct. 29, 2009. Seven students from the Maryland School for the Blind visited NASA and participated in activities to learn about NASA'smission, functions, and careers. Photo Credit: (NASA/Paul E. Alers)

Barbie Dolls stand by during the STS-134 Tweetup, Thursday, April 28, 2011, at Kennedy Space Center in Cape Canaveral, Fla. About 150 NASA Twitter followers attended the event. Photo Credit: (NASA/Paul E. Alers)

Guests look on from the terrace of Operations Support Building II as space shuttle Endeavour launches from pad 39A on the STS-130 mission early Monday, Feb. 8, 2010, at Kennedy Space Center in Cape Canaveral, Fla. Endeavour and its crew will deliver to the International Space Station a third connecting module, the Italian-built Tranquility node and the seven-windowed cupola, which will be used as a control room for robotics. The mission will feature three spacewalks. Photo Credit: (NASA/Paul E. Alers)

A researcher with the Genesis and Rapid Intensification Processes (GRIP) experiment works aboard the NASA DC-8 during a flight over the Gulf of Mexico, Tuesday, Aug. 17, 2010. GRIP is a NASA Earth science field experiment in 2010 that is being conducted to better understand how tropical storms form and develop into major hurricanes. Photo Credit: (NASA/Paul E. Alers)

Retired Marine Corps Gen. Anthony Zinni, Chairman of the Board at BAE Systems, speaks to those gathered at the 2009 NASA Executive Summit, Tuesday, Oct. 6, 2009, at the Ronald Reagan Building in Washington. (Photo Credit: (NASA/Paul E. Alers)

Producer/Director Toni Myers, left, speaks to a reporter as Deputy Administrator for NASA Lori Garver, second from left, is interviewed by another on the red carpet prior to the World Premiere of "Hubble 3D", screened at the Smithsonian's Air and Space Museum Tuesday evening, March 9, 2010, in Washington. Photo Credit: (NASA/Paul E. Alers)

An unidentified student speaks with astronauts aboard the Internatiional Space Station (ISS) via downlink during an event at the U.S. Department of Education, Thursday, Nov. 5, 2009, in Washington. NASA Administrator Charles Bolden and Secretary of Education Arne Duncan hosted Washington area middle and high school students Thursday for a live discussion with astronauts aboard the International Space Station. The event was part of the 10th annual celebration of International Education Week. Photo Credit: (NASA/Paul E. Alers)

Actress June Lockhart speaks at a program entitled Human Spaceflight: The Kennedy Legacy, Wednesday, May 25, 2011, in the concert hall at the John F. Kennedy Center for the Performing Arts in Washington. The event marked the 50th Anniversary of President John F. Kennedy's Special Message to the Congress on Urgent National Needs in which he stated "landing a man on the moon and returning him safely to earth". Photo Credit: (NASA/Paul E. Alers)

NASA Administrator Charles Bolden visits with students from Albert Hill Middle School during a visit to the MathScience Innovation Center, Friday, Jan. 28, 2011, in Richmond, Va. During his visit, Bolden highlighted the importance of science, technology, engineering and math, or STEM, as he shared his life experiences with the students. Photo Credit:(NASA/Paul E. Alers)

Dr. Robert Braun, NASA Chief Technologist, second from left, makes a point, as panelists Leland Melvin, Assoicate Administrator for NASA Education, left, Dr. Laurie Leshin, NASA Deputy Associate Administrator Exploration Systems Mission Directortorate, and Dr. Waleed Abdalati, NASA Chief Scientist, right, look on during a panel discussion at the NASA Future Forum held at the Riggs Alumni Center on the campus of the University of Maryland, Thursday, Aug. 11, 2011 in College Park, Md. Photo Credit: (NASA/Paul E. Alers)

NASA astronaut Mike Massimino, far left, Sesame Street's Elmo and NASA astronaut Doug Wheelock, far right, speak at the STS-135 Tweetup, Thursday, July 7, 2011, at Kennedy Space Center in Cape Canaveral, Fla. Elmo asked the astronauts questions about living and working in space. About 150 NASA Twitter followers attended the event. The STS-135 mission will be NASA's last space shuttle launch. Photo Credit: (NASA/Paul E. Alers)

STS-127 Commander Mark Polansky, standing left, talks about the recent mission to White House interns at the Eisenhower Executiive Office Building in Washington, Thursday, Sept. 24, 2009. Seated from left are crew members Julie Payette, Christopher Cassidy, David Wolf, Douglas Hurley and Thomas Marshburn. Photo Credit: (NASA/Paul E. Alers)

Students from the Maryland School for the Blind learn about astronauts during NASA's Disability Mentoring Day, Thursday, April 7, 2011, at NASA Headquarters in Washignton. Photo Credit: (NASA/Paul E. Alers)

Actor and Producer Levar Burton tweets with two devices during the STS-134 Tweetup, Thursday, April 28, 2011, at Kennedy Space Center in Cape Canaveral, Fla. About 150 NASA Twitter followers attended the event. Photo Credit: (NASA/Paul E. Alers)

Errol Korn, seated left, deploys a dropsonde experiment over the Gulf of Mexico during a flight aboard the NASA DC-8 as Janel Thomas, a University of Maryland Baltimore County (UMBC) graduate student, and Bob Pasken, look on , Tuesday, Aug. 17, 2010. The Genesis and Rapid Intensification Processes (GRIP) experiment is a NASA Earth science field experiment in 2010 that is being conducted to better understand how tropical storms form and develop into major hurricanes. Photo Credit: (NASA/Paul E. Alers)

Dr. Henry Hertzfeld, from George Washington University, speaks about technology investments and their benefits during a panel discussion at the 2011 NASA Future Forum held at the Riggs Alumni Center on the campus of the University of Maryland, Thursday, Aug. 11, 2011, in College Park, Md. Photo Credit: (NASA/Paul E. Alers)

Apollo astronaut Alan Bean, center, laughs at a comment made by Apollo astronaut Charles Duke, right, as Apollo astronaut Buzz Aldrin, left, looks on during a live television interview on Monday, July 20, 2009, at NASA Headquarters in Washington. Monday marked the 40th Anniversary of the historic landing of Apollo 11 on the Moon. Photo Credit: (NASA/Paul E. Alers)

Actress June Lockhart livens up the audience after donning a NASA cap during a program entitled Human Spaceflight: The Kennedy Legacy, Wednesday, May 25, 2011, in the concert hall at the John F. Kennedy Center for the Performing Arts in Washington. The event marked the 50th Anniversary of President John F. Kennedy's Special Message to the Congress on Urgent National Needs in which he stated "landing a man on the moon and returning him safely to earth". Photo Credit: (NASA/Paul E. Alers)

NASA Administrator Charles Bolden, left, speaks to members of the Congressional Black Caucus during their weekly meeting at the U.S. Capitol in Washington, Wednesday, Jan. 13, 2010. Photo Credit: (NASA/Paul E. Alers)

Michael Neufeld, chair of the division of space history at the National Air and Space Museum, speaks during an Apollo History and Legacy roundtable discussion, Thursday, July 16, 2009, at NASA Headquarters in Washington. Photo Credit: (NASA/Paul E. Alers)

USAID Administrator Rajiv Shah speaks prior to signing a five-year memorandum of understanding with NASA, Monday, April 25, 2011, at NASA Headquarters in Washington. The agreement formalizes ongoing agency collaborations that use Earth science data to address developmental challenges, and to assist in disaster mitigation and humanitarian responses. The agreement also encourages NASA and USAID to apply geospatial technologies to solve development challenges affecting the United States and developing countries. Photo Credit: (NASA/Paul E. Alers)

Cristina Guidi, deputy director, Constellation Systems Division, Exploration Systems Mission Directorate, NASA Headquarters, speaks during an Apollo History and Legacy roundtable discussion, Thursday, July 16, 2009, at NASA Headquarters in Washington. Photo Credit: (NASA/Paul E. Alers)

Ken Wheeler and his daughter Kayla listen intently to President Barack Obama's speech following his swearing in as they stand along Pennsylvania Avenue in Washington, Monday, Jan. 21, 2013. The Wheeler's traveled from Cincinnati, Ohio to attend the event. Photo Credit: (NASA/Paul E. Alers)

Richard Hay, @WinObs, looks at an astronaut boot, during the two-day STS-132 Launch Tweetup at Kennedy Space Center, Thursday, May 13, 2010, in Cape Canaveral, Fla. NASA Twitter followers in attendance will have the opportunity to take a tour of NASA's Kennedy Space Center, view the space shuttle launch and speak with shuttle technicians, engineers, astronauts and managers. Photo Credit: (NASA/Paul E. Alers)

Seated from left, Bill Danchi, Senior Astrophysicist and Program Scientist at NASA Headquarters, Francis Everitt, Principal Investigator for the Gravity Probe B Mission at Stanford University, Rex Geveden, President of Teledyne Brown Engineering, Colleen Hartman, a research professor at George Washington University, and Clifford Will, Professor of Physics at Washington University in St. Louis, Mo., conduct a press conference, Wednesday, May 4, 2011, to discuss NASA's Gravity Probe B (GP-B) mission which has confirmed two key predictions derived from Albert Einstein's general theory of relativity, which the spacecraft was designed to test. at NASA Headquarters in Washington. Photo Credit: (NASA/Paul E. Alers)

Visitors to the USA Science and Engineering Festival look over the many exhibits, Saturday, Oct. 23, 2010, at Freedom Plaza in Washington. NASA, joined with more than 500 science organizations this weekend to inspire the next generation of scientists and engineers during the first national science and engineering festival held in the nation's capital. Photo Credit: (NASA/Paul E. Alers)

Doug McCuiston, Director, Mars Exploration Program, talks during a Mars Program Update where prominent scientists discussed evidence of water on Mars, current Program status, including the 7th Anniversary of the Mars rovers and the upcoming Mars Science Laboratory mission and previewing exciting discoveries to come, Thursday, Jan. 13, 2011, at the Smithsonian National Air and Space Museum in Washington. Photo Credit: (NASA/Paul E. Alers)

NASA STS-129 mission specialist Leland Melvin, standing, speaks to students assembled as fellow crew members Barry Wilmore, seated left, Mike Foreman and Randy Bresnick, seated right, look on during a presentation about their recent mission, Thursday, Jan. 14, 2010, at the Smithsonian National Air and Space Museum in Washington. Photo Credit: (NASA/Paul E. Alers)

NASA Deputy Administrator Lori Garver, right, along with Assistant Administrator for Legislative and Intergovernmental Affairs L. Seth Statler, meets with STS-128 astronauts Patrick Forrester, left, Jose Hernandez and Christer Fugelsang, of the European Space Agency, at NASA Headquarters, Tuesday, Nov. 3, 2009, in Washington. Photo Credit: (NASA/Paul E. Alers)

NASA Administrator Charles Bolden, left, and U.S. Environmental Protection Agency (EPA) Administrator Lisa P. Jackson, right, sign a Memorandum of Agreement (MOA) to promote collaboration between the two agencies for cooperation in environmental and Earth sciences and environmental management applications as students from the Howard University Middle School of Mathematics and Science look on, Monday, April 26, 2010, at the school in Washington. Photo Credit: (NASA/Paul E. Alers)

A student from the Maryland School For the Blind asks a question while learning about Meteorites, Asteroids and Comets during NASA's Disability Mentoring Day, Thursday, April 7, 2011, at NASA Headquarters in Washignton. Photo Credit: (NASA/Paul E. Alers)

Dr. James L. Green, Director of Planetary Science at NASA, right, speaks with Dr. Robert Farquar, an executive for space exploration at KinetX Inc., during a symposium commemorating a quarter-century of comet discoveries, Friday, Sept. 10, 2010, in the Knight studio at the Newseum in Washington. The International Sun-Earth Explorer-3 (ISEE-3) spacecraft flew past the comet Giacobini-Zinner on Sept. 11, 1985 which established a foundation of discoveries that continue today. Photo Credit: (NASA/Paul E. Alers)

Actor Seth Green, a NASA Twitter follower, holds up his mobile device bearing the NASA emblem during the STS-134 Tweetup, Thursday, April 28, 2011, at Kennedy Space Center in Cape Canaveral, Fla. About 150 NASA Twitter followers attended the event. Photo Credit: (NASA/Paul E. Alers)

NASA astronaut TJ Creamer talks about his experience in space during a "Tweetup" at NASA Headquarters, Thursday, July 29, 2010, in Washington. Creamer, who spent 161 days living aboard the International Space Station as part of the Expedition 22/23 crew, set up the orbiting outpost's live Internet connection and posted updates about the mission to his Twitter account, sending the first live tweet from orbit. Photo Credit: (NASA/Paul E. Alers)

NASA chief historian Steven Dick, seated left, along with John Logsdon, Roger Launius, Michael Neufeld, Cristina Guidi and Craig Nelson, are seen at an Apollo History and Legacy roundtable discussion, Thursday, July 16, 2009, at NASA Headquarters in Washington. Photo Credit: (NASA/Paul E. Alers)

Students from the Maryland School for the Blind learn about space food from NASA Public Affairs specialist Nora Normandy, right, during Disability Mentoring Day, Thursday, April 7, 2011, at NASA Headquarters in Washington. Photo Credit (NASA/Paul E. Alers)

Paul K. Martin, nominee for Inspector General at NASA, right, answers questions during his confirmation hearing in front of the Senate Committee on Commerce, Science and Transportation, Thursday, Oct. 15, 2009, on Capitol Hill in Washington. At left is Dr. Elizabeth M. Robinson, nominee for Chief Financial Officer for NASA. Photo Credit: (NASA/Paul E. Alers)

Scott Altman, who commanded the STS-125 mission to the Hubble Space Telescope, far left on stage, speaks during a press conference, Wednesday, Sept. 9, 2009, after astronomers declared the telescope a fully rejuvenated observatory with the release Wednesday of observations from four of its six operating science instruments at NASA Headquarters in Washington. Photo Credit: (NASA/Paul E. Alers)

Astronauts Tracy Caldwell Dyson, flight engineer on Expeditions 23 and 24, left, and Doug Wheelock, Expedition 24 flight engineer and commander of Expedition 25, discuss their mission to the International Space Station during a visit to NASA Headquarters in Washington, Wednesday, March 16, 2011.

NASA Administrator Charles F. Bolden appears in front of the U.S. House of Representatives Committee on Science and Technology to discuss the President’s FY 2011 budget request, Thursday, Feb. 25, 2010, on Capitol Hill in Washington. Photo Credit: (NASA/Paul E. Alers)

Lori Garver, NASA Deputy Administrator, second from left, stands with members of the STS-125 crew and IMAX officials including Producer/Director Toni Myers, fifth from right, prior to the World Premiere of "Hubble 3D", screened at the Smithsonian's Air and Space Museum Tuesday evening, March 9, 2010, in Washington. Members of the STS-125 crew, dressed in their blue flight suits from left are; Mike Massimino, John Grunsfeld, Megan McArthur, Greg Johnson and Scott Altman. Photo Credit: (NASA/Paul E. Alers)

NASA Astronaut Clay Anderson speaks to NASA Twitter followers during the STS-134 Tweetup, Thursday, April 28, 2011, at Kennedy Space Center in Cape Canaveral, Fla. About 150 NASA Twitter followers attended the event. Photo Credit: (NASA/Paul E. Alers)

The full moon is seen as it rises near the National Mall, Saturday, March 19, 2011, in Washington. The full moon tonight is called a "Super Moon" since it is at its closest to Earth. Photo Credit: (NASA/Paul E. Alers)

The NASA DC-8 airplane sits on the tarmac, Monday, Aug. 16, 2010, at Fort Lauderdale Hollywood International Airport in Fort Lauderdale, Fla. , as preparations continue for its part in the GRIP experiment. The Genesis and Rapid Intensification Processes (GRIP) experiment is a NASA Earth science field experiment in 2010 that is being conducted to better understand how tropical storms form and develop into major hurricanes. Photo Credit: (NASA/Paul E. Alers)