Astronaut Don Pettit took this photograph of a U.S. spacesuit helmet with his reflection prominent on the helmet's visor inside the International Space Station's Quest airlock.
Astronaut Don Pettit took this photograph of a U.S. spacesuit helmet with his reflection prominent on the helmet’s visor inside the International Space Station’s Quest airlock.

Most of the Expedition 72 crew was off duty on Tuesday while a pair of NASA astronauts conducted human research and studied biotechnology. Two spacewalks are now planned this month for science maintenance and station upgrades.

Flight Engineers Don Pettit and Nick Hague kept up a host of advanced space research aboard the International Space Station on Tuesday. The NASA duo explored how microgravity affects the human body and studied ways to produce fresh food and oxygen in space.

Pettit focused on human research Tuesday as he collected his saliva, blood, and urine samples. He processed and stowed those samples in a science freezers for later analysis to understand how weightlessness affects station crew members. Hague serviced samples of micro-algae exposing them to various light intensities to observe how they produce oxygen and nutrients in microgravity. Observations may promote crew health and advance life support systems on future spacecraft.

At the end of his shift, Hague refilled tanks and liquid cooling ventilation garments with water preparing a pair of spacesuits for a pair of upcoming spacewalks. He and Commander Suni Williams of NASA are scheduled to begin the first spacewalk at 7 a.m. EST on Thursday, Jan. 16. The pair will exit the orbital outpost’s Quest airlock and spend about six-and-a-half hours replacing a rate gyro assembly, servicing the NICER X-ray telescope, and preparing the Alpha Magnetic Spectrometer for future upgrades.

Mission managers will discuss that spacewalk and a second one planned for Jan. 23 on NASA+ beginning at 2 p.m. EST on Friday. NASA+ will also broadcast both spacewalks beginning at 5:30 a.m. with the Jan. 23 excursion also starting at 7 a.m.

Meanwhile, Williams and NASA Flight Engineer Butch Wilmore had the day off on Tuesday following a busy day on Monday. Cosmonauts Alexey Ovchinin, Ivan Vagner, and Aleksandr Gorbunov also relaxed Tuesday as they observed the Eastern Orthodox Christmas holiday.


Learn more about station activities by following the space station blog@space_station and @ISS_Research on X, as well as the ISS Facebook and ISS Instagram accounts.

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