Station Science Top News: March 10, 2022
Results of the International Space Station Brain DTI study found changes in the brain’s white matter tracts during spaceflight. Microstructural changes that couldn’t be explained by aging were observed seven months after returning to Earth. Increased understanding of how spaceflight affects the human brain is necessary to ensure safer long-duration missions.
Researchers used diffusion MRI, an advanced imaging analysis technique that identifies microstructural changes in the brain’s white matter. White matter contains nerve fibers and passes messages through the nervous system. Results indicate pre- to postflight changes in various white matter tracts connecting the two brain hemispheres, outer cortical regions with inner parts of the brain, and regions associated with language processing. The scientists argue more research on the topic is needed because “current countermeasures exist for muscle and bone loss, but if future research provides evidence that countermeasures are necessary for the brain, then we must begin to answer this challenging question.”
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The station-mounted Neutron star Interior Composition Explorer, or NICER, telescope has observed the merging of multimillion-degree X-ray spots on the surface of a magnetar, a super-magnetized stellar core, for the first time. This unique set of observations will help guide scientists to a more complete understanding of the interplay between the crust and magnetic field of these extreme objects.
A magnetar is a type of isolated neutron star — the crushed core left behind when a massive star explodes. Magnetars sport the strongest magnetic fields known, up to 10 trillion times more intense than a refrigerator magnet. The field represents an enormous storehouse of energy that, when disturbed, can power an outburst of enhanced X-ray activity lasting from months to years. As was recently published, on Oct. 10, 2020, NASA’s Neil Gehrels Swift Observatory discovered an outburst from a new magnetar, which astronomers estimate to be about 13,000 lightyears away. NICER measurements from that day show that the X-ray emission exhibited three close hot spots with every rotation. NICER tracked how bright spots slowly wandered across the object’s surface while decreasing in size. The largest spot merged with a smaller one — something that hadn’t been seen before.
In this extreme ultraviolet view from NASA’s Solar Dynamics Observatory, loops of ionized gas trace magnetic fields emerging from the solar surface. Credits: NASA/SDO