Nobel Laureate and James Webb Space Telescope project scientist Dr. John Mather takes a selfie with the telescope. May 4, 2016 was a rare day for JWST, as it briefly faced the cleanroom observation window. The telescope was eventually rotated face-down in prep for the installation of the flight instruments. Credit: Meredith Gibb

Dr. Nancy Grace Roman visits James Webb Space Telescope (JWST) and the Hubble Project Team. Dr. John Mather.

John Mather, Project Scientist for JWST, faces the James Webb Space Telescope primary mirror, taking a selfie, NASA/Goddard Space Flight Center, Greenbelt, MD, May 4, 2016

John Mather, Project Scientist for JWST, faces the James Webb Space Telescope primary mirror, NASA/Goddard Space Flight Center, Greenbelt, MD, May 4, 2016

John Mather, Project Scientist for JWST, faces the James Webb Space Telescope primary mirror, taking a selfie, NASA/Goddard Space Flight Center, Greenbelt, MD, May 4, 2016

NASA Astrophycist Dr. John Mather speaks, Tuesday, July 27, 2010, at the Smithsonian National Air and Space Museum in Washington. Mather was speaking as part of a ceremony with STS-132 astronaut Piers Sellers who returned a replica of the Nobel Prize that is in the museum's collection and was flown aboard STS-132 Atlantis. The prize was won by Mather and University of California, Berkeley researcher George Smoot in 2006 for their work using the Cosmic Background Explorer Satellite to understand the big-bang theory of the universe.Photo Credit: (NASA/Paul E. Alers)

James Webb Space Telescope (JWST) Town Hall - Panel question and answer - Bill Ochs; Dr. John Mather; Dr. Eric Smith; Thomas Zurbuchen; Center Director Chris Scolese; NASA Administrator Charlie Bolden.

James Webb Space Telescope (JWST) Town Hall - Panel question and answer - Bill Ochs; Dr. John Mather; Dr. Eric Smith; Thomas Zurbuchen; Center Director Chris Scolese; NASA Administrator Charlie Bolden.

STS-132 astronaut Piers Sellers, left, and Dr. John Mather are seen with a replica of Mather's Nobel Prize, Tuesday, July 27, 2010, at the Smithsonian National Air and Space Museum in Washington. Sellers returned the replica that is in the museum's collection and was flown aboard STS-132 Atlantis. The prize was won by Mather and University of California, Berkeley researcher George Smoot in 2006 for their work using the Cosmic Background Explorer Satellite to understand the big-bang theory of the universe. Photo Credit: (NASA/Paul E. Alers)

Dr. John Mather, NASA Goddard Space Flight Center scientist and Nobel Laureate, center, presents Gen. John R. “Jack” Dailey, director of the Smithsonian National Air and Space Museum, left, with a a replica of Mather’s Nobel Prize medal that flew in space aboard STS-132, as astronaut Piers Sellers looks on, during a ceremony at the museum, Tuesday, July 27, 2010, in Washington. Photo Credit: (NASA/Paul E. Alers)

NASA Astrophycist Dr. John Mather, at podium, speaks Tuesday, July 27, 2010, at the Smithsonian National Air and Space Museum in Washington as museum director Gen. John R. "Jack" Dailey, U.S. Marine Corps ret. and STS-132 astronaut Piers Sellers look on. Sellers returned a replica of the Nobel Prize that is in the museum's collection and was flown aboard STS-132 Atlantis. The prize was won by Mather and University of California, Berkeley researcher George Smoot in 2006 for their work using the Cosmic Background Explorer Satellite to understand the big-bang theory of the universe.Photo Credit: (NASA/Paul E. Alers)

STS-132 astronaut Piers Sellers, at podium, acknowleges museum director Ret. Gen. John R. "Jack" Dailey, seated left, and NASA astrophycisist Dr. John Mather, center, during a presentation, Tuesday, July 27, 2010, at the Smithsonian National Air and Space Museum in Washington. Sellers returned a replica of the Nobel Prize that is in the museum's collection and was flown aboard STS-132 Atlantis. The prize was won by Mather and University of California, Berkeley researcher George Smoot in 2006 for their work using the Cosmic Background Explorer Satellite to understand the big-bang theory of the universe.Photo Credit: (NASA/Paul E. Alers)

Dr. Nancy Grace Roman visits James Webb Space Telescope (JWST) and the Hubble Project Team. Dr. John Mather.

AIAA American Institute for Aeronautics and Astronautics science fair winners visited Goddard on July 17, 2017. Dr. John Mather, Nobel Prize winner, poses with group near JWST clean room.