NASA Administrator Jim Bridenstine speaks during the Smithsonian National Air and Space Museum's Spirit of Apollo event commemorating the 50th anniversary of Apollo 8, Tuesday, Dec. 11, 2018 at the Washington National Cathedral in Washington, DC. Apollo 8 was humanity's first journey to another world, taking astronauts Frank Borman, Jim Lovell, and William Anders to the Moon and back in December of 1968. Photo Credit: (NASA/Joel Kowsky)

Apollo 8 astronaut Jim Lovell shakes hands with NASA Administrator Jim Bridenstine after being introduced during the Smithsonian National Air and Space Museum's Spirit of Apollo event commemorating the 50th anniversary of Apollo 8, Tuesday, Dec. 11, 2018 at the Washington National Cathedral in Washington, DC. Apollo 8 was humanity's first journey to another world, taking astronauts Frank Borman, Jim Lovell, and William Anders to the Moon and back in December of 1968. Photo Credit: (NASA/Joel Kowsky)

NASA Administrator Charles Bolden delivers a tribute during a memorial service celebrating the life of Neil Armstrong, Thursday, Sept. 13, 2012, at the Washington National Cathedral. Armstrong, the first man to walk on the moon during the 1969 Apollo 11 mission, died Saturday, Aug. 25. He was 82. Photo Credit: (NASA/Bill Ingalls)

Apollo 8 astronaut Jim Lovell speaks during the Smithsonian National Air and Space Museum's Spirit of Apollo event commemorating the 50th anniversary of Apollo 8, Tuesday, Dec. 11, 2018 at the Washington National Cathedral in Washington, DC. Apollo 8 was humanity's first journey to another world, taking astronauts Frank Borman, Jim Lovell, and William Anders to the Moon and back in December of 1968. Photo Credit: (NASA/Joel Kowsky)

Apollo 8 astronaut Jim Lovell is seen during the Smithsonian National Air and Space Museum's Spirit of Apollo event commemorating the 50th anniversary of Apollo 8, Tuesday, Dec. 11, 2018 at the Washington National Cathedral in Washington, DC. Apollo 8 was humanity's first journey to another world, taking astronauts Frank Borman, Jim Lovell, and William Anders to the Moon and back in December of 1968. Photo Credit: (NASA/Joel Kowsky)

The audience is seen while a video about the Apollo 8 mission is shown on monitors during the Smithsonian National Air and Space Museum's Spirit of Apollo event commemorating the 50th anniversary of Apollo 8, Tuesday, Dec. 11, 2018 at the Washington National Cathedral in Washington, DC. Apollo 8 was humanity's first journey to another world, taking astronauts Frank Borman, Jim Lovell, and William Anders to the Moon and back in December of 1968. Photo Credit: (NASA/Joel Kowsky)

The International Space Station is seen in this twenty-second exposure as it flies over the Washington National Cathedral, Wednesday, Nov. 29, 2017. Onboard are NASA astronauts Joe Acaba, Mark Vande Hei, and Randy Bresnik; Russian cosmonauts Alexander Misurkin and Sergey Ryanzansky; and ESA astronaut Paolo Nespoli. Photo Credit: (NASA/Bill Ingalls)

NASA Administrator Jim Bridenstine speaks during the Smithsonian National Air and Space Museum's Spirit of Apollo event commemorating the 50th anniversary of Apollo 8, Tuesday, Dec. 11, 2018 at the Washington National Cathedral in Washington, DC. Apollo 8 was humanity's first journey to another world, taking astronauts Frank Borman, Jim Lovell, and William Anders to the Moon and back in December of 1968. Photo Credit: (NASA/Joel Kowsky)

NASA Deputy Administrator Lori Garver, right, shares a moment with Apollo 17 mission commander Gene Cernan, the last man to walk on the moon, left, as U.S. Sen. Kay Bailey Hutchison, R-Texas, center looks on prior to a memorial service celebrating the life of Neil Armstrong, Thursday, Sept. 13, 2012, at the Washington National Cathedral. Armstrong, the first man to walk on the moon during the 1969 Apollo 11 mission, died Saturday, Aug. 25. He was 82. Photo Credit: (NASA/Bill Ingalls)

The Washington National Cathedral Choir performs a choral performance of Apollo 8's Christmas Eve broadcast during the Smithsonian National Air and Space Museum's Spirit of Apollo event commemorating the 50th anniversary of Apollo 8, Tuesday, Dec. 11, 2018 at the Washington National Cathedral in Washington, DC. Apollo 8 was humanity's first journey to another world, taking astronauts Frank Borman, Jim Lovell, and William Anders to the Moon and back in December of 1968. Photo Credit: (NASA/Joel Kowsky)

Apollo 8 astronaut Jim Lovell speaks during the Smithsonian National Air and Space Museum's Spirit of Apollo event commemorating the 50th anniversary of Apollo 8, Tuesday, Dec. 11, 2018 at the Washington National Cathedral in Washington, DC. Apollo 8 was humanity's first journey to another world, taking astronauts Frank Borman, Jim Lovell, and William Anders to the Moon and back in December of 1968. Photo Credit: (NASA/Joel Kowsky)

Apollo 8 astronaut Jim Lovell speaks during the Smithsonian National Air and Space Museum's Spirit of Apollo event commemorating the 50th anniversary of Apollo 8, Tuesday, Dec. 11, 2018 at the Washington National Cathedral in Washington, DC. Apollo 8 was humanity's first journey to another world, taking astronauts Frank Borman, Jim Lovell, and William Anders to the Moon and back in December of 1968. Photo Credit: (NASA/Joel Kowsky)

Apollo 8 astronaut Jim Lovell points to the lines from Genesis in his flight plan that were read during a television broadcast by him, Frank Borman, and William Anders as they orbited the Moon on Christmas Eve in 1968, Tuesday, Dec. 11, 2018 at the Washington National Cathedral in Washington, DC. Lovell's flight plan, which is usually displayed at the Adler Planetarium in Chicago, was one of the artifacts from the mission that were on display during the Smithsonian National Air and Space Museum's Spirit of Apollo event commemorating the 50th anniversary of Apollo 8. Apollo 8 was humanity's first journey to another world, taking astronauts Frank Borman, Jim Lovell, and William Anders to the Moon and back in December of 1968. Photo Credit: (NASA/Joel Kowsky)

The Most Reverend Michael Curry speaks during the Smithsonian National Air and Space Museum's Spirit of Apollo event commemorating the 50th anniversary of Apollo 8, Tuesday, Dec. 11, 2018 at the Washington National Cathedral in Washington, DC. Apollo 8 was humanity's first journey to another world, taking astronauts Frank Borman, Jim Lovell, and William Anders to the Moon and back in December of 1968. Photo Credit: (NASA/Joel Kowsky)

Apollo 8 astronaut Jim Lovell speaks during the Smithsonian National Air and Space Museum's Spirit of Apollo event commemorating the 50th anniversary of Apollo 8, Tuesday, Dec. 11, 2018 at the Washington National Cathedral in Washington, DC. Apollo 8 was humanity's first journey to another world, taking astronauts Frank Borman, Jim Lovell, and William Anders to the Moon and back in December of 1968. Photo Credit: (NASA/Joel Kowsky)

NASA Administrator Jim Bridenstine speaks during the Smithsonian National Air and Space Museum's Spirit of Apollo event commemorating the 50th anniversary of Apollo 8, Tuesday, Dec. 11, 2018 at the Washington National Cathedral in Washington, DC. Apollo 8 was humanity's first journey to another world, taking astronauts Frank Borman, Jim Lovell, and William Anders to the Moon and back in December of 1968. Photo Credit: (NASA/Joel Kowsky)

An image of Neil Armstrong is projected on a television screen as attendees sit in the Nave during a memorial service celebrating the life of Neil Armstrong at the Washington National Cathedral, Thursday, Sept. 13, 2012. Armstrong, the first man to walk on the moon during the 1969 Apollo 11 mission, died Saturday, Aug. 25. He was 82. Photo Credit: (NASA/Bill Ingalls)

The Washington National Cathedral is seen lit up with space imagery prior to the Smithsonian National Air and Space Museum's Spirit of Apollo event commemorating the 50th anniversary of Apollo 8, Tuesday, Dec. 11, 2018 in Washington, DC. Apollo 8 was humanity's first journey to another world, taking astronauts Frank Borman, Jim Lovell, and William Anders to the Moon and back in December of 1968. Photo Credit: (NASA/Joel Kowsky)

Former U.S. Sen. John Glenn, left, and Buzz Aldrin shake hands prior to a memorial service celebrating the life of Neil Armstrong, Thursday, Sept. 13, 2012, at the Washington National Cathedral. Armstrong, the first man to walk on the moon during the 1969 Apollo 11 mission, died Saturday, Aug. 25. He was 82. Photo Credit: (NASA/Bill Ingalls)

The Most Reverend Michael Curry speaks during the Smithsonian National Air and Space Museum's Spirit of Apollo event commemorating the 50th anniversary of Apollo 8, Tuesday, Dec. 11, 2018 at the Washington National Cathedral in Washington, DC. Apollo 8 was humanity's first journey to another world, taking astronauts Frank Borman, Jim Lovell, and William Anders to the Moon and back in December of 1968. Photo Credit: (NASA/Joel Kowsky)

Ellen Stofan, director of the Smithsonian's National Air and Space Museum, speaks about NASA's Apollo program during the Smithsonian National Air and Space Museum's Spirit of Apollo event commemorating the 50th anniversary of Apollo 8, Tuesday, Dec. 11, 2018 at the Washington National Cathedral in Washington, DC. Apollo 8 was humanity's first journey to another world, taking astronauts Frank Borman, Jim Lovell, and William Anders to the Moon and back in December of 1968. Photo Credit: (NASA/Joel Kowsky)

John H. Dalton, former United States Secretary of the Navy, delivers the Reading during a memorial service celebrating the life of Neil Armstrong at the Washington National Cathedral, Thursday, Sept. 13, 2012. Armstrong, the first man to walk on the moon during the 1969 Apollo 11 mission, died Saturday, Aug. 25. He was 82. Photo Credit: (NASA/Bill Ingalls)

The Very Reverend Randy Hollerith, Dean of the Washington National Cathedral welcomes everyone to the Smithsonian National Air and Space Museum's Spirit of Apollo event commemorating the 50th anniversary of Apollo 8, Tuesday, Dec. 11, 2018 at the Washington National Cathedral in Washington, DC. Apollo 8 was humanity's first journey to another world, taking astronauts Frank Borman, Jim Lovell, and William Anders to the Moon and back in December of 1968. Photo Credit: (NASA/Joel Kowsky)

Apollo 8 astronaut Jim Lovell, left, NASA Administrator Jim Bridenstine, second from left, Ellen Stofan, Director of the Smithsonian's National Air and Space Museum, second from right, and the Very Reverend Randy Hollerith, Dean of the Washington National Cathedral, are seen as they watch a video on the Apollo 8 mission during the Smithsonian National Air and Space Museum's Spirit of Apollo event commemorating the 50th anniversary of Apollo 8, Tuesday, Dec. 11, 2018 at the Washington National Cathedral in Washington, DC. Apollo 8 was humanity's first journey to another world, taking astronauts Frank Borman, Jim Lovell, and William Anders to the Moon and back in December of 1968. Photo Credit: (NASA/Joel Kowsky)

Apollo 8 astronaut Jim Lovell is seen during the Smithsonian National Air and Space Museum's Spirit of Apollo event commemorating the 50th anniversary of Apollo 8, Tuesday, Dec. 11, 2018 at the Washington National Cathedral in Washington, DC. Apollo 8 was humanity's first journey to another world, taking astronauts Frank Borman, Jim Lovell, and William Anders to the Moon and back in December of 1968. Photo Credit: (NASA/Joel Kowsky)

Apollo 8 astronaut Jim Lovell acknowledges a stating ovation after being introduced during the Smithsonian National Air and Space Museum's Spirit of Apollo event commemorating the 50th anniversary of Apollo 8, Tuesday, Dec. 11, 2018 at the Washington National Cathedral in Washington, DC. Apollo 8 was humanity's first journey to another world, taking astronauts Frank Borman, Jim Lovell, and William Anders to the Moon and back in December of 1968. Photo Credit: (NASA/Joel Kowsky)

Apollo 8 astronaut Jim Lovell speaks during the Smithsonian National Air and Space Museum's Spirit of Apollo event commemorating the 50th anniversary of Apollo 8, Tuesday, Dec. 11, 2018 at the Washington National Cathedral in Washington, DC. Apollo 8 was humanity's first journey to another world, taking astronauts Frank Borman, Jim Lovell, and William Anders to the Moon and back in December of 1968. Photo Credit: (NASA/Joel Kowsky)

The Washington National Cathedral is seen illuminated during the Smithsonian National Air and Space Museum's Spirit of Apollo event commemorating the 50th anniversary of Apollo 8, Tuesday, Dec. 11, 2018 in Washington, DC. Apollo 8 was humanity's first journey to another world, taking astronauts Frank Borman, Jim Lovell, and William Anders to the Moon and back in December of 1968. Photo Credit: (NASA/Joel Kowsky)

The Space Window at the Washington National Cathedral is seen during the Smithsonian National Air and Space Museum's Spirit of Apollo event commemorating the 50th anniversary of Apollo 8, Tuesday, Dec. 11, 2018 in Washington, DC. Apollo 8 was humanity's first journey to another world, taking astronauts Frank Borman, Jim Lovell, and William Anders to the Moon and back in December of 1968. Photo Credit: (NASA/Joel Kowsky)

Ellen Stofan, director of the Smithsonian's National Air and Space Museum, speaks about NASA's Apollo program during the Smithsonian National Air and Space Museum's Spirit of Apollo event commemorating the 50th anniversary of Apollo 8, Tuesday, Dec. 11, 2018 at the Washington National Cathedral in Washington, DC. Apollo 8 was humanity's first journey to another world, taking astronauts Frank Borman, Jim Lovell, and William Anders to the Moon and back in December of 1968. Photo Credit: (NASA/Joel Kowsky)

Ellen Stofan, director of the Smithsonian's National Air and Space Museum, speaks about NASA's Apollo program during the Smithsonian National Air and Space Museum's Spirit of Apollo event commemorating the 50th anniversary of Apollo 8, Tuesday, Dec. 11, 2018 at the Washington National Cathedral in Washington, DC. Apollo 8 was humanity's first journey to another world, taking astronauts Frank Borman, Jim Lovell, and William Anders to the Moon and back in December of 1968. Photo Credit: (NASA/Joel Kowsky)

Apollo 8 astronaut Jim Lovell, left, Andrew Johnston, Vice President for Astronomy and Collections at Chicago's Adler Planetarium, center, and Ellen Stofan, Director of the Smithsonian's National Air and Space Museum, right, look at Lovell's Apollo 8 flight plan during the Smithsonian National Air and Space Museum's Spirit of Apollo event commemorating the 50th anniversary of Apollo 8, Tuesday, Dec. 11, 2018 at the Washington National Cathedral in Washington, DC. Apollo 8 was humanity's first journey to another world, taking astronauts Frank Borman, Jim Lovell, and William Anders to the Moon and back in December of 1968. Photo Credit: (NASA/Joel Kowsky)

A monitor showing a portrait of the Apollo 8 crew is seen during the Smithsonian National Air and Space Museum's Spirit of Apollo event commemorating the 50th anniversary of Apollo 8, Tuesday, Dec. 11, 2018 at the Washington National Cathedral in Washington, DC. Apollo 8 was humanity's first journey to another world, taking astronauts Frank Borman, Jim Lovell, and William Anders to the Moon and back in December of 1968. Photo Credit: (NASA/Joel Kowsky)

Apollo 17 mission commander Gene Cernan, the last man to walk on the moon, speaks during a memorial service celebrating the life of Neil Armstrong at the Washington National Cathedral, Thursday, Sept. 13, 2012. Armstrong, the first man to walk on the moon during the 1969 Apollo 11 mission, died Saturday, Aug. 25. He was 82. Photo Credit: (NASA/Bill Ingalls)

Apollo 17 mission commander Gene Cernan, the last man to walk on the moon, looks skyward during a memorial service celebrating the life of Neil Armstrong at the Washington National Cathedral, Thursday, Sept. 13, 2012. Armstrong, the first man to walk on the moon during the 1969 Apollo 11 mission, died Saturday, Aug. 25. He was 82. Photo Credit: (NASA/Bill Ingalls)

Ellen Stofan, Director of Smithsonian's National Air and Space Museum, left, and NASA Administrator Jim Bridenstine look at Jim Lovell's Apollo 8 flight plan with Andrew Johnston, Vice President for Astronomy and Collections at Chicago's Adler Planetarium, during the Smithsonian National Air and Space Museum's Spirit of Apollo event commemorating the 50th anniversary of Apollo 8, Tuesday, Dec. 11, 2018 at the Washington National Cathedral in Washington, DC. Apollo 8 was humanity's first journey to another world, taking astronauts Frank Borman, Jim Lovell, and William Anders to the Moon and back in December of 1968. Photo Credit: (NASA/Joel Kowsky)

Apollo 8 astronaut Jim Lovell poses for a picture with his flight plan from the mission during the Smithsonian National Air and Space Museum's Spirit of Apollo event commemorating the 50th anniversary of Apollo 8, Tuesday, Dec. 11, 2018 at the Washington National Cathedral in Washington, DC. Apollo 8 was humanity's first journey to another world, taking astronauts Frank Borman, Jim Lovell, and William Anders to the Moon and back in December of 1968. Photo Credit: (NASA/Joel Kowsky)

Apollo 8 astronaut Jim Lovell is seen with his flight plan from the mission that was among the artifacts on display during the Smithsonian National Air and Space Museum's Spirit of Apollo event commemorating the 50th anniversary of Apollo 8, Tuesday, Dec. 11, 2018 at the Washington National Cathedral in Washington, DC. Apollo 8 was humanity's first journey to another world, taking astronauts Frank Borman, Jim Lovell, and William Anders to the Moon and back in December of 1968. Photo Credit: (NASA/Joel Kowsky)

Carol Armstrong, center, her son Eric, right, and daughter Molly Van Wagenen hold their hands to their hearts during a memorial service celebrating the life of Neil Armstrong at the Washington National Cathedral, Thursday, Sept. 13, 2012. Armstrong, the first man to walk on the moon during the 1969 Apollo 11 mission, died Saturday, Aug. 25. He was 82. Photo Credit: (NASA/Bill Ingalls)

NASA Administrator Charles Bolden, back to camera, speaks with Carol Armstrong after presenting her with a U.S. Flag that was flown at half-mast over Mission Control at Johnson Space Center in Houston, on the day of her husband’s passing, during a memorial service celebrating the life of Neil Armstrong at the Washington National Cathedral, Thursday, Sept. 13, 2012. Armstrong, the first man to walk on the moon during the 1969 Apollo 11 mission, died Saturday, Aug. 25. He was 82. Photo Credit: (NASA/Bill Ingalls)

The interior of the Washington National Cathedral is seen illuminated prior to the Smithsonian National Air and Space Museum's Spirit of Apollo event commemorating the 50th anniversary of Apollo 8, Tuesday, Dec. 11, 2018 in Washington, DC. Apollo 8 was humanity's first journey to another world, taking astronauts Frank Borman, Jim Lovell, and William Anders to the Moon and back in December of 1968. Photo Credit: (NASA/Joel Kowsky)

Attendees to the memorial service for Neil Armstrong sing a hymnal, Thursday, Sept. 13, 2012, at the Washington National Cathedral. Armstrong, the first man to walk on the moon during the 1969 Apollo 11 mission, died Saturday, Aug. 25. He was 82. Photo Credit: (NASA/Bill Ingalls)

The Very Reverend Randy Hollerith, Dean of the Washington National Cathedral speaks at the beginning of the Smithsonian National Air and Space Museum's Spirit of Apollo event commemorating the 50th anniversary of Apollo 8, Tuesday, Dec. 11, 2018 at the Washington National Cathedral in Washington, DC. Apollo 8 was humanity's first journey to another world, taking astronauts Frank Borman, Jim Lovell, and William Anders to the Moon and back in December of 1968. Photo Credit: (NASA/Joel Kowsky)

The Washington National Cathedral Choir performs a choral performance of Apollo 8's Christmas Eve broadcast during the Smithsonian National Air and Space Museum's Spirit of Apollo event commemorating the 50th anniversary of Apollo 8, Tuesday, Dec. 11, 2018 at the Washington National Cathedral in Washington, DC. Apollo 8 was humanity's first journey to another world, taking astronauts Frank Borman, Jim Lovell, and William Anders to the Moon and back in December of 1968. Photo Credit: (NASA/Joel Kowsky)

Former Secretary of the Treasury John Snow speaks during a memorial service celebrating the life of Neil Armstrong at the Washington National Cathedral, Thursday, Sept. 13, 2012. Armstrong, the first man to walk on the moon during the 1969 Apollo 11 mission, died Saturday, Aug. 25. He was 82. Photo Credit: (NASA/Bill Ingalls)