SpaceX’s Dragon cargo capsule is leaving the International Space Station today after a month-long stay at the orbiting lab. This particular spacecraft is carrying extra special cargo back to Earth: biological samples from former NASA astronaut Scott Kelly. Kelly recently stayed on the ISS for 340 days to help researchers better understand what happens to the human body during long-term spaceflight. His samples, collected during his stay on the ISS, will provide a snapshot of the body changes Kelly went through — but the fluids have to make it back to our planet in one piece first.
This particular spacecraft is carrying extra special cargo
On Monday and Tuesday, astronauts onboard the ISS packed up the Dragon with more than 3,700 pounds of supplies, including Kelly’s bodily fluids and other samples that will be used for biotechnology research, physical science research, and more. NASA then started the Dragon’s undocking process earlier this morning; the station’s Canadian robotic arm detached the spacecraft from the ISS, in order to move the capsule far enough away from the station. Today at 9:18AM ET, ESA astronaut Tim Peake will release the Dragon from the arm, and the capsule will fire its onboard thrusters three times to take it farther away from the station. NASA’s coverage of the release begins at 9AM ET.
Afterward, the Dragon will take itself out of orbit around 2PM ET and then plummet back down to Earth. Unlike Orbital ATK’s expendable Cygnus capsule, the Dragon is designed to survive the descent through Earth’s atmosphere. Parachutes will help to slow the capsule during its fall, allowing it to touch down gently in the Pacific Ocean. Eventually, SpaceX hopes to land the crewed version of its Dragon by reigniting engines onboard the capsule, to perform a controlled landing on solid ground. It’s how SpaceX intends to land Dragons on Mars in 2018. But the company has yet to land a capsule this way.
Splash down of the Dragon is scheduled for 2:55PM ET, though NASA won’t provide coverage of the event. However, the space agency will provide an update shortly after the Dragon is recovered, letting people know how the spacecraft handled its fall to Earth.