Hurley and Behnken are bringing back a commemorative U.S. flag that was left on the space station by the crew of the last shuttle mission (which happened to include Doug Hurley).
Their undocking from the ISS is scheduled for approximately 7:34 pm (23:34 UTC) Saturday, and the splashdown at 2:42 pm (18:42 UTC) on Sunday.
This is SpaceX's final test flight and is providing data on the performance of the Falcon 9 rocket, Crew Dragon spacecraft and ground systems, as well as in-orbit, docking, splashdown, and recovery operations.
The Crew Dragon spacecraft is certified for around 114 days in space. Eastern time. Several engine thrusters fired to further separate the spacecraft from the space station.
"Not intuitive, but Isaias may actually help make nice weather on landing a few hundred miles west, " Zebulon Scoville, NASA's flight director, wrote on Twitter Saturday morning.
Delays to the Commercial Crew Program's first crewed flight and only two crewed Soyuz missions to the Station in 2020 necessitated a crew reduction from six to three beginning in April 2020. They are trying to get as much data as they can about this return, because the goal of this mission, the demonstration 2 or demo 2 mission, is to show that this capsule is safe to take people to and from space, not just any people, but civilians.
"If the weather isn't good or the sea states aren't good, we're going to take our time bringing Bob and Doug home".
'Now is the entry, descent and splashdown phase after we undock, hopefully a little bit later today, ' Hurley said in a farewell ceremony aboard the ISS that was broadcast on NASA TV.
At 5:45 pm EDT (21:45 UTC), the two will wave goodbye to Cassidy, Anatoli Ivanishin, and Ivan Vagner before closing the hatches that separate Endeavour and the Station.
The departure on the same day has been scheduled for 4.34 pm PT.
In the return flight, the Dragon will be traveling at about 28,160kmh before re-entering the Earth's atmosphere, where it will rapidly slow and heat up.
Fortunately, SpaceX's Dragon capsule is heading for waters off Florida's other coast.
NASA and SpaceX have been keeping a close eye on Hurricane Isaias, which is expected to approach Florida's east coast this weekend.
After the spacecraft splashes down, a recovery ship with more than 40 NASA and SpaceX personnel onboard will rendezvous with the capsule and hoist it out of the water and onto the ship's main deck. There, the crew will emerge from the capsule and receive all necessary medical test and checkouts. If the weather forecast looks acceptable, the capsule will leave the space station around 7:30 pm ET and begin its 19-hour trek to a splashdown off the coast of Florida.
Dragon Endeavour will then be brought back to the Cape Canaveral Air Force Station, Florida, where engineers and technicians will thoroughly inspect the craft before refurbishing it for its next mission, Crew-2, in Spring 2021.
NASA footage showed the capsule drifting slowly away from the ISS in the darkness of space, closing out two months aboard for the first U.S. astronauts to reach the orbiting lab on an American spacecraft in almost a decade.