Station Science Top News: May 31, 2024

by ISS Program Science Office | 2024-06-03

Researchers demonstrated that the expression of genes associated with anemia decreased during spaceflight or bedrest on the ground and then increased once flight or bedrest ended. These findings suggest the body has a mechanism to modulate space- and bedrest-induced anemia - knowledge that could lead to development of better mitigation strategies for future missions.

The Canadian Space Agency MARROW investigation looked at how microgravity affects bone marrow and identified increased hemolysis (destruction of red blood cells) during spaceflight as a major contributor to space anemia. Directly assessing blood cell production requires invasive procedures, but measuring changes in gene expression could be a better alternative for monitoring the health of astronauts.

A male astronaut helps another male astronaut take a blood sample aboard the International Space Station. — Astronaut Tim Kopra (left) performs blood draw on European Space Agency (ESA) astronaut Tim Peake in the Columbus module. **Credit: NASA**

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Thermalbright®N, a polyhedral oligomeric silsesquioxane (POSS) material, resisted erosion caused by atomic oxygen in space better than various other polymer materials tested. The finding suggests that incorporating this material into spacecraft could enhance resistance to atomic oxygen erosion and help ensure the success of future missions.

MISSE-16-Commercial tested the effects of space exposure on a variety of materials, including a fabric with imbedded sensors, 3D-printed polymers, radiation protection biomaterials, dried microbes, paraffin wax thermal protection, and thin solar cells. POSS are three-dimensional silicon-oxygen molecules with multiple uses, including in thermoplastics and electronic devices and as flame retardants.

View of the Materials ISS Experiment Flight Facility — View of the Materials International Space Station Experiment Flight Facility (MISSE-FF) taken by the External High Definition Camera. **Credit: NASA**

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Advances in instrument design and new calibration techniques have improved the accuracy of solar spectral irradiance measurements. A report on the first five years of measurements by the station’s Total and Spectral Solar Irradiance Sensor (TSIS) includes the descending phase of solar cycle 24 (the last solar minimum) and the ascending phase of cycle 25. These data are essential to interpreting how Earth responds to solar spectral variability.

TSIS measures total solar irradiance and solar spectral irradiance, which affect Earth’s atmosphere, climate, and atmospheric and oceanic circulations. Knowing the magnitude and variability of solar irradiance contributes to understanding the connection between the Sun and Earth’s climate. This knowledge could enhance space weather predictions and help protect humans and satellites in space as well as electric power transmissions and radio communications on the ground.

Photo taken of SpaceX-13 Total and Spectral Solar Irradiance Sensor (TSIS-1) during EVA tool fit-checks and sharp edge inspection. — Total and Spectral Solar Irradiance Sensor (TSIS) Thermal Pointing System (TPS) in its deployed configuration during spacewalk tool fit-checks and sharp edge inspection at NASA's Johnson Space Center. **Credit: NASA**