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Alex
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NASA's Perseverance rover has recorded the first audio clips captured on the surface of Mars, beaming back to Earth guttural sounds of wind gusting on the red planet.

The first-of-its-kind audio was released Monday, along with extraordinary new video footage of the rover as it descended and landed last Thursday. The images are among the most sophisticated yet taken of Mars, and offer never-before-seen views of the rover approaching its landing site.

Thomas Zurbuchen, associate administrator for NASA’s Science Mission Directorate, said the new images and audio are "the closest you can get to landing on Mars without putting on a pressure suit."

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The nearest solar system to our own may actually host two potentially life-supporting planets, a new study reports.

In 2016, scientists discovered a roughly Earth-size world circling Proxima Centauri, part of the three-star Alpha Centauri system, which lies about 4.37 light-years from Earth. The planet, known as Proxima b, orbits in the "habitable zone," the range of distances from a star at which liquid water could exist on a world's surface. (A second planet, Proxima c, was later discovered circling the star as well, but it orbits farther away, beyond the habitable zone's outer limits.)

There's considerable debate about the true habitability of Proxima b, however, given that its parent star is a red dwarf. These stars, the most common in the Milky Way, are small and dim, so their habitable zones lie very close in — so close, in fact, that planets residing there tend to be tidally locked, always showing the same face to their host stars, just as the moon always shows Earth its near side. In addition, red dwarfs are prolific flarers, especially when they're young, so it's unclear if their habitable-zone worlds can hold onto their atmospheres for long.

The other two stars in the Alpha Centauri trio, however, are sunlike — a pair called Alpha Centauri A and B, which together make up a binary orbiting the same center of mass. And Alpha Centauri A may have its own habitable-zone planet, according to the new research, which was published online today (Feb. 10) in the journal Nature Communications.

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A new study found that electrons can reach ultra-relativistic energies for very special conditions in the magnetosphere when space is devoid of plasma.

Recent measurements from NASA's Van Allen Probes spacecraft showed that electrons can reach ultra-relativistic energies flying at almost the speed of light. Hayley Allison, Yuri Shprits and collaborators from the German Research Centre for Geosciences have revealed under which conditions such strong accelerations occur. They had already demonstrated in 2020 that during solar storm plasma waves play a crucial role for that. However, it was previously unclear why such high electron energies are not achieved in all solar storms. In the journal Science Advances, Allison, Shprits and colleagues now show that extreme depletions of the background plasma density are crucial.

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Before the Apollo era, the moon was thought to be dry as a desert due to the extreme temperatures and harshness of the space environment. Many studies have since discovered lunar water: ice in shadowed polar craters, water bound in volcanic rocks, and unexpected rusty iron deposits in the lunar soil. Despite these findings, there is still no true confirmation of the extent or origin of lunar surface water.

The prevailing theory is that positively charged hydrogen ions propelled by the solar wind bombard the lunar surface and spontaneously react to make water (as hydroxyl (OH-) and molecular (H2O)). However, a new multinational study published in Astrophysical Journal Letters proposes that solar wind may not be the only source of water-forming ions. The researchers show that particles from Earth can seed the moon with water, as well, implying that other planets could also contribute water to their satellites.

Water is far more prevalent in space than astronomers first thought, from the surface of Mars to Jupiter's moons and Saturn's rings, comets, asteroids and Pluto; it has even been detected in clouds far beyond our solar system. It was previously assumed that water was incorporated into these objects during the formation of the solar system, but there is growing evidence that water in space is far more dynamic. Though the solar wind is a likely source for lunar surface water, computer models predict that up to half of it should evaporate and disappear at high-latitude regions during the approximately three days of the full moon when it passes within Earth's magnetosphere.

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