NASA astronauts Bob Behnken and Doug Hurley pose after they arrived at the Kennedy Space Center to prepare for the launch of SpaceX's Crew Dragon capsule, at Cape Canaveral, Florida, U.S. May 20, 2020.

A business near NASA's Kennedy Space Center shows support for SpaceX on the day of the company's first launch carrying humans to space in Titusville, Florida, U.S. May 27, 2020.

A pelican takes flight as the SpaceX Crew Dragon sits atop a Falcon 9 booster rocket on Pad 39A at Kennedy Space Center in Cape Canaveral, Florida, U.S. May 26, 2020.

Crews work on the SpaceX Crew Dragon, attached to a Falcon 9 booster rocket, as it sits horizontal on Pad39A at the Kennedy Space Center in Cape Canaveral, Florida, U.S. May 26, 2020.

U.S. President Donald Trump signs his name as he tours the Neil Armstrong Operations and Checkout Facility at the Kennedy Space Center in Cape Canaveral, Florida, U.S., May 27, 2020.

NASA astronauts Bob Behnken and Doug Hurley arrive at the Kennedy Space Center to prepare for the launch of SpaceX's Crew Dragon capsule, at Cape Canaveral, Florida, U.S. May 20, 2020.

NASA astronauts Douglas Hurley (L) and Robert Behnken walk out of the Neil A. Armstrong Operations and Checkout Building at NASA’s Kennedy Space Center during a dress rehearsal ahead of NASA’s SpaceX Demo-2 mission to the International Space Station in Cape Canaveral, Florida, U.S. May 23, 2020. Picture taken May 23, 2020. NASA/Brandon Garner/Handout via REUTERS.

Crews work on the SpaceX Crew Dragon, attached to a Falcon 9 booster rocket, as it sits horizontal on Pad39A at the Kennedy Space Center in Cape Canaveral, Florida, U.S. May 26, 2020.

Photographers set up remote cameras for NASA's first manned flight since 2011 aboard the SpaceX Crew Dragon on a Falcon 9 booster rocket on Pad39A at the Kennedy Space Center in Cape Canaveral, Florida, U.S. May 26, 2020.

NASA astronauts Bob Behnken and Doug Hurley gesture after they arrive at the Kennedy Space Center to prepare for the launch of SpaceX's Crew Dragon capsule, at Cape Canaveral, Florida, U.S. May 20, 2020.

NASA astronauts Douglas Hurley (L) and Robert Behnken pose while participating in a dress rehearsal for launch at the agency’s Kennedy Space Center ahead of NASA’s SpaceX Demo-2 mission to the International Space Station in Cape Canaveral, Florida, U.S. May 23, 2020. Picture taken May 23, 2020. NASA/Kim Shiflett/Handout via REUTERS.

People wait to watch the launch of a SpaceX Falcon 9 rocket and Crew Dragon spacecraft carrying NASA astronauts Douglas Hurley and Robert Behnken during the NASA's SpaceX Demo-2 mission to the International Space Station from NASA's Kennedy Space Center before the launched was called off due to threatening weather conditions in Cape Canaveral, Florida, U.S. May 27, 2020.

Crews work on the SpaceX Crew Dragon, attached to a Falcon 9 booster rocket, as it sits horizontal on Pad39A at the Kennedy Space Center in Cape Canaveral, Florida, U.S. May 26, 2020.

NASA astronaut Douglas Hurley waves from his Tesla as they pass the VAB heading to Pad39A for the launch of the SpaceX Crew Dragon on a Falcon 9 booster rocket from the Kennedy Space Center in Cape Canaveral, Florida, U.S. May 27, 2020.

Crews work on the SpaceX Crew Dragon, attached to a Falcon 9 booster rocket, as it sits horizontal on Pad39A at the Kennedy Space Center in Cape Canaveral, Florida, U.S. May 26, 2020.

U.S. President Donald Trump signs his name as he, Vice President Mike Pence, second lady Karen Pence and first lady Melania Trump tour the Neil Armstrong Operations and Checkout Facility at the Kennedy Space Center in Cape Canaveral, Florida, U.S., May 27, 2020.

NASA astronaut Douglas Hurley steps into a Tesla X as he and fellow astronaut Robert Behnken are taken to Pad39A before the launch of a SpaceX Falcon 9 rocket and Crew Dragon spacecraft at the Kennedy Space Center, in Cape Canaveral, Florida, U.S., May 27, 2020.

NASA astronauts Douglas Hurley and Robert Behnken head to launch Pad39A to board a SpaceX Falcon 9 rocket during NASA's SpaceX Demo-2 mission to the International Space Station from NASA's Kennedy Space Center in Cape Canaveral, Florida, U.S., May 27, 2020.

The sun sets behind the Vehicle Assembly Building as preparations continue for the NASA’s SpaceX Demo-2 mission to the International Space Station at NASA’s Kennedy Space Center in Cape Canaveral in Florida May 25, 2020. Picture taken May 25, 2020. NASA/Joel Kowsky/Handout via REUTERS.

Crews work on the SpaceX Crew Dragon, attached to a Falcon 9 booster rocket, as it sits horizontal on Pad39A at the Kennedy Space Center in Cape Canaveral, Florida, U.S. May 26, 2020.

U.S. President Donald Trump tours the Neil Armstrong Operations and Checkout Facility with Vice President Mike Pence, second lady Karen Pence and first lady Melania Trump prior to witnessing the launch of a SpaceX Falcon 9 rocket carrying two NASA astronauts to the International Space Station at the Kennedy Space Center in Cape Canaveral, Florida, U.S., May 27, 2020.

NASA astronauts Bob Behnken and Doug Hurley arrive at the Kennedy Space Center to prepare for the launch of SpaceX's Crew Dragon capsule, at Cape Canaveral, Florida, U.S. May 20, 2020.

NASA astronauts Bob Behnken and Doug Hurley pose with NASA Administrator Jim Bridenstine
 and Kennedy Space Center Director Bob Cabana after they arrived at the Kennedy Space Center to prepare for the launch of SpaceX's Crew Dragon capsule, at Cape Canaveral, Florida, U.S. May 20, 2020.

Crews work on the SpaceX Crew Dragon, attached to a Falcon 9 booster rocket, as it sits horizontal on Pad39A at the Kennedy Space Center in Cape Canaveral, Florida, U.S. May 26, 2020.

U.S. President Donald Trump signs his name as he and first lady Melania Trump tour the Neil Armstrong Operations and Checkout Facility at the Kennedy Space Center in Cape Canaveral, Florida, U.S., May 27, 2020.

NASA astronauts Bob Behnken and Doug Hurley are met by NASA Administrator Jim Bridenstine
 and Kennedy Space Center Director Bob Cabana after they arrived at the Kennedy Space Center to prepare for the launch of SpaceX's Crew Dragon capsule, at Cape Canaveral, Florida, U.S. May 20, 2020.

NASA astronaut Douglas Hurley rehearses putting on his SpaceX spacesuit in the Astronaut Crew Quarters inside the Neil A. Armstrong Operations and Checkout Building at the Kennedy Space Center ahead of NASA’s SpaceX Demo-2 mission to the International Space Station in Cape Canaveral, Florida, U.S. May 23, 2020. Picture taken May 23, 2020. NASA/Kim Shiflett/Handout via REUTERS.

SpaceX founder Elon Musk and NASA Administrator Jim Bridenstine attend the walkout of NASA astronauts Douglas Hurley and Robert Behnken before the launch of a SpaceX Falcon 9 rocket and Crew Dragon spacecraft at the Kennedy Space Center, in Cape Canaveral, Florida, U.S., May 27, 2020.

A screen showing the countdown clock is seen with SpaceX Falcon 9 rocket and Crew Dragon spacecraft in the background as launch from NASA's Kennedy Space Center was scrubbed, in Cape Canaveral, Florida, U.S. May 27, 2020.

The crew access arm is swung into position to a SpaceX Falcon 9 rocket with the company's Crew Dragon spacecraft onboard on the launch pad at Launch Complex 39A at NASA’s Kennedy Space Center as preparations continue for the Demo-2 mission to the International Space Station, in Cape Canaveral, Florida, U.S. May 21, 2020. NASA/Bill Ingalls/Handout via REUTERS.