The Soyuz MS-13 spacecraft will undock at approximately 05:49am UTC from the International Space Station. It will return to Earth with astronauts Aleksandr Skvortsov, Christina Koch and Luca Parmitano onboard. Landing will be at approximately 09:14am UTC.
The core stage of the 'Space Launch System' will undergo a 'Green Run' test, where the stage and major components will be tested as a full stack to ensure safety of the vehicle. Part of the testing will involve a 8 minute 'Hot Fire' of the core stage, demonstrating performance similar to an actual launch.
The OSIRIS-REx is a NASA asteroid study and sample-return mission. The mission's main goal is to obtain a sample of at least 60 grams from 101955 Bennu, a carbonaceous near-Earth asteroid, and return the sample to Earth for a detailed analysis. Rehearsals will be performed before the sampling event, during which the solar arrays will be raised into a Y-shaped configuration to minimize the chance of dust accumulation during contact and provide more ground clearance in case the spacecraft tips over (up to 45°) during contact. The descent will be very slow to minimize thruster firings prior to contact in order to reduce the likelihood of asteroid surface contamination by unreacted hydrazine propellant. Contact with the surface of Bennu will be detected using accelerometers, and the impact force will be dissipated by a spring in the TAGSAM arm. Upon surface contact by the TAGSAM instrument, a burst of nitrogen gas will be released, which will blow regolith particles smaller than 2 cm (0.8 in) into the sampler head at the end of the robotic arm. A five-second timer will limit collection time to mitigate the chance of a collision. After the timer expires, the back-away maneuver will initiate a safe departure from the asteroid.
When Hayabusa-2 flies past Earth in December 2020, it will release the capsule spinning at one revolution per three seconds. The capsule will re-enter the Earth's atmosphere at 12 km/s and it will deploy a radar-reflective parachute at an altitude of about 10 km, and eject its heat-shield, while transmitting a position beacon signal. The sample capsule will land at the Woomera Test Range in Australia.