NASA Space Station On-Orbit Update 15 October, 2021 - Soyuz Thruster Firing Problem

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The Soyuz MS-18 crew ship and the Nauka multipurpose laboratory module. (Sept. 28, 2021)

Three Russian inhabitants of the International Space Station are preparing to depart for Earth on Saturday night. Meanwhile, the rest of the Expedition 65 crew worked on a variety of life science activities as well as important orbital plumbing duties on Friday.

Russia's Soyuz MS-18 crew ship will return to Earth just after midnight Eastern time on Sunday with Soyuz Commander Oleg Novitskiy and spaceflight participants Yulia Peresild and Klim Shipenko. They will undock from the Nauka multipurpose laboratory module on Saturday at 9:14 p.m. EDT. Next, they will soar through the atmosphere in the Soyuz descent module. Finally, the Soyuz parachutes will deploy above Kazakhstan bringing the trio to a safe landing at 12:36 a.m. Sunday (10:36 a.m. Kazakh time).

Novitskiy spent Friday wrapping up packing station hardware, science experiments and personal items inside the Soyuz vehicle. The three-time station resident from Roscosmos also tested the lower body negative pressure suit that may help him more quickly adjust to gravity after returning to Earth.

Meanwhile, science and maintenance continued as usual aboard the orbital lab. The crew members had a busy schedule on their hands today working on vein scans, orbital plumbing, and microbial analysis.

Station Commander Thomas Pesquet of ESA (European Space Agency) scanned the leg, neck and heart veins of Flight Engineer Akihiko Hoshide of the Japan Aerospace Exploration during the morning using an ultrasound device. Doctors on the ground assisted the duo in real time for the Vascular Aging study that is exploring why astronaut's veins show accelerated aging characteristics after a long-term space mission.

NASA Flight Engineers Shane Kimbrough and Mark Vande Hei worked throughout the day configuring the station's new toilet located in the Tranquility module. Kimbrough also performed simulated robotic maneuvers for a cognition test, while Vande Hei worked on a CubeSat deployer before transferring cargo inside the Cygnus space freighter. NASA Flight Engineer Megan McArthur spent the afternoon inside the U.S. Quest airlock installing a deck panel.

Cosmonauts Anton Shkaplerov and Pyotr Dubrov partnered together for a microbial study in the station's Russian segment during the afternoon. The duo collected and stowed samples of microbes living on the station for further analysis.

At 5:02 a.m. EDT today, Russian flight controllers conducted a scheduled thruster firing test on the Soyuz MS-18 spacecraft that is scheduled to return to Earth Saturday night with three crew members aboard. The thruster firing unexpectedly continued after the end of the test window, resulting in a loss of attitude control for the International Space Station at 5:13 a.m. Within 30 minutes, flight controllers regained attitude control of the space station, which is now in a stable configuration. The crew was awake at the time of the event and was not in any danger.

Flight controllers are continuing to evaluate data on the station's brief attitude change due to the thruster firing. NASA and Roscosmos are collaborating to understand the root cause.

Joey Roulette of the New York Times had the following quote from Russian mission control "'Oleg, take it easy, the station was turned by 57 degrees, no big deal,' a Russian mission control official in Moscow was quoted as saying to the astronaut by Interfax, a Russian news agency. 'We had to make sure that engines are in order, this is important.'"

"'Station, Houston space-to-ground two, we see the loss of attitude control warning,' NASA mission control in Houston alerted its astronauts on the station, instructing them to begin emergency procedures in the crew's warning book. Flight controllers regained control of the station within 30 minutes, Ms. Cheshier said."

Coverage of the Soyuz MS-18 crew's farewells, undocking, and landing will air live on NASA TV, the agency's website, and the NASA app at the following times tomorrow (all EDT):

4:15 p.m. - Farewells (at about 4:35 p.m.)
9 p.m. - Soyuz undocking and a replay of hatch closure (undocking at 9:14 p.m.)
11:15 p.m. - Deorbit burn (11:42 p.m.) and landing (12:36 a.m.)

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