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What happens when your brain can't tell which way is up?

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This illustration shows the configuration for conducting neurocognitive assessments for the Neuromapping study aboard the International Space Station.
Credit: Credits: NASA
In space, there is no "up" or "down." That can mess with the human brain and affect the way people move and think in space. An investigation on the International Space Station seeks to understand how the brain changes in space and ways to deal with those changes.
Previous research and first-hand reports suggest that humans have a harder time controlling physical movement and completing mental tasks in microgravity. Astronauts have experienced problems with balance and perceptual illusions -- feeling as if, for example, they are switching back and forth between right-side-up and upside down.
The Spaceflight Effects on Neurocognitive Performance: Extent, Longevity, and Neural Bases (NeuroMapping) study is examining changes in both brain structure and function and determining how long it takes to recover after returning from space.
Researchers are using both behavioral assessments and brain imaging. Astronauts complete timed obstacle courses and tests of their spatial memory, or the ability to mentally picture and manipulate a three-dimensional shape, before and after spaceflight. The spatial memory test also is performed aboard the station, along with sensory motor adaptation tests and computerized exercises requiring them to move and think simultaneously. Astronauts are tested shortly after arriving aboard the station, mid-way through and near the end of a six-month flight.
Structural and functional magnetic resonance imaging (MRI) scans of the brain are done pre-flight and post-flight.
"We are looking at the volume of different structures in the brain and whether they change in size or shape during spaceflight," said principal investigator Rachael D. Seidler, director of the University of Michigan's Neuromotor Behavior Laboratory.
Functional MRIs involve astronauts completing a task during the imaging, which will show researchers which parts of the brain they rely on to do so.
According to Seidler, both the behavioral assessment and brain imaging are important to help identify the relationship between physical changes in the brain and those in behavior.
"On Earth, your vestibular -- or balance -- system tells you how your head moves relative to gravity, but in space, the gravity reference is gone," Seidler said. "That causes these perceptual illusions, as well as difficulty coordinating movement of the eyes and head."
These difficulties could have serious consequences for astronauts, especially when changing between gravitational environments, such as landing on Mars. In those cases, astronauts will need to be able to perform tasks such as using tools and driving a rover, and they must be capable of escape in a landing emergency.
Identifying the physical mechanisms behind changes in behavior and how much time it takes to adapt will help researchers determine how best to help space explorers compensate. The study results could also reveal whether astronauts return to "normal" post-flight because the brain changes back, or if the brain instead learns to compensate for the changes that happened in space.
Scientists know that brain changes and adaptations happen here on Earth as well. As people age, for example, they use more brain networks than a younger person does to perform the same task. Chemotherapy, injury and illness also can trigger such adaptation. Co-investigator Patricia A. Reuter-Lorenz, chair of psychology at the University of Michigan, said a major benefit of this study is that the subjects are fit, healthy astronauts. That will make it possible to apply the findings across a range of causes.
Learning more about how the human brain changes in space will help scientists better understand the ways it can recover and adapt in space, and on Earth.
At least here on Earth, people can usually tell which way is up.

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The above post is reprinted from materials provided by NASA/Johnson Space Center. Note: Materials may be edited for content and length.
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A cosmic sackful of black coal

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This image from the Wide Field Imager on the MPG/ESO 2.2-meter telescope shows part of the huge cloud of dust and gas known as the Coalsack Nebula. The dust in this nebula absorbs and scatters the light from background stars.
Credit: ESO
The Coalsack Nebula is located about 600 light-years away in the constellation of Crux. This huge, dusky object forms a conspicuous silhouette against the bright, starry band of the Milky Way and for this reason the nebula has been known to people in the southern hemisphere for as long as our species has existed.
The Spanish explorer Vicente Yáñez Pinzón first reported the existence of the Coalsack Nebula to Europe in 1499. The Coalsack later garnered the nickname of the Black Magellanic Cloud, a play on its dark appearance compared to the bright glow of the two Magellanic Clouds, which are in fact satellite galaxies of the Milky Way. These two bright galaxies are clearly visible in the southern sky and came to the attention of Europeans during Ferdinand Magellan's explorations in the 16th century. However, the Coalsack is not a galaxy. Like other dark nebulae, it is actually an interstellar cloud of dust so thick that it prevents most of the background starlight from reaching observers.
A significant number of the dust particles in dark nebulae have coats of frozen water, nitrogen, carbon monoxide and other simple organic molecules. The resulting grains largely prevent visible light from passing through the cosmic cloud. To get a sense of how truly dark the Coalsack is, back in 1970, the Finnish astronomer Kalevi Mattila published a study estimating that the Coalsack has only about 10 percent of the brightness of the encompassing Milky Way. A little bit of background starlight, however, still manages to get through the Coalsack, as is evident in the new ESO image and in other observations made by modern telescopes.
The little light that does make it through the nebula does not come out the other side unchanged. The light we see in this image looks redder than it ordinarily would. This is because the dust in dark nebulae absorbs and scatters blue light from stars more than red light, tinting the stars several shades more crimson than they would otherwise be.
Millions of years in the future the Coalsack's dark days will come to an end. Thick interstellar clouds like the Coalsack contain lots of dust and gas -- the fuel for new stars. As the stray material in the Coalsack coalesces under the mutual attraction of gravity, stars will eventually light up, and the coal "nuggets" in the Coalsack will "combust," almost as if touched by a flame.

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The above post is reprinted from materials provided by ESO. Note: Materials may be edited for content and length.
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Hubble's planetary portrait captures changes in Jupiter's Great Red Spot

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This new image from the largest planet in the Solar System, Jupiter, was made during the Outer Planet Atmospheres Legacy (OPAL) programme. The images from this programme make it possible to determine the speeds of Jupiter's winds, to identify different phenomena in its atmosphere and to track changes in its most famous features.
Credit: NASA, ESA, A. Simon (GSFC), M. Wong (UC Berkeley), and G. Orton (JPL-Caltech)
Scientists using the NASA/ESA Hubble Space Telescope have produced new maps of Jupiter that show the continuing changes in its famous Great Red Spot. The images also reveal a rare wave structure in the planet's atmosphere that has not been seen for decades. The new image is the first in a series of annual portraits of the Solar System's outer planets, which will give us new glimpses of these remote worlds, and help scientists to study how they change over time.
In this new image of Jupiter a broad range of features has been captured, including winds, clouds and storms. The scientists behind the new images took pictures of Jupiter using Hubble's Wide Field Camera 3 over a ten-hour period and have produced two maps of the entire planet from the observations. These maps make it possible to determine the speeds of Jupiter's winds, to identify different phenomena in its atmosphere and to track changes in its most famous features.
The new images confirm that the huge storm, which has raged on Jupiter's surface for at least three hundred years, continues to shrink, but that it may not go out without a fight. The storm, known as the Great Red Spot, is seen here swirling at the centre of the image of the planet. It has been decreasing in size at a noticeably faster rate from year to year for some time. But now, the rate of shrinkage seems to be slowing again, even though the spot is still about 240 kilometres smaller than it was in 2014.
The spot's size is not the only change that has been captured by Hubble. At the centre of the spot, which is less intense in colour than it once was, an unusual wispy filament can be seen spanning almost the entire width of the vortex. This filamentary streamer rotates and twists throughout the ten-hour span of the Great Red Spot image sequence, distorted by winds that are blowing at 540 kilometres per hour.
There is another feature of interest in this new view of our giant neighbour. Just north of the planet's equator, researchers have found a rare wave structure, of a type that has been spotted on the planet only once before, decades ago by the Voyager 2 mission, which was launched in 1977. In the Voyager 2 images the wave was barely visible and astronomers began to think its appearance was a fluke, as nothing like it has been seen since, until now.
The current wave was found in a region dotted with cyclones and anticyclones. Similar waves -- called baroclinic waves -- sometimes appear in Earth's atmosphere where cyclones are forming. The wave may originate in a clear layer beneath the clouds, only becoming visible when it propagates up into the cloud deck, according to the researchers.
The observations of Jupiter form part of the Outer Planet Atmospheres Legacy (OPAL) programme, which will allow Hubble to dedicate time each year to observing the outer planets. In addition to Jupiter,Neptune and Uranus have already been observed as part of the programme and maps of these planets will be placed in the public archive. Saturn will be added to the series later. The collection of maps that will be built up over time will help scientists not only to understand the atmospheres of giant planets in the Solar System, but also the atmospheres of our own planet and of the planets that are being discovered around other stars.

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The above post is reprinted from materials provided by ESA/Hubble Information Centre. Note: Materials may be edited for content and length.
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