A 2nd Planet has been Confirmed for Proxima Centauri

An artist's illustration of the Proxima Centauri system. Proxima b is on the left, while Proxima C is on the right. Image Credit: Lorenzo Santinelli

Our closest stellar neighbour is Proxima Centauri, a small red dwarf star about 4.2 light years away from us. It’s the third member of the Alpha Centauri group, and even though it’s so close, it can’t be seen with the naked eye. In 2016 astronomers discovered a planet orbiting Proxima Centuari, named Proxima Centauri b. That planet was confirmed only a few days ago.

Now, astronomers have confirmed the existence of a second planet, Proxima Centauri c.

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InSight has been Sensing Dust Devils Sweep Past its Landing Site

The InSight lander has been on the surface of Mars for about a year, and a half dozen papers were just published outlining some results from the mission. Though InSight’s primary mission is to gather evidence on the interior of Mars—InSight stands for Interior Exploration using Seismic Investigations, Geodesy, and Heat Transport—the lander also keeps track of Martian Meteorology. A new paper reports that InSight has found gravity waves, swirling dust devils, and a steady background rumble of infrasound.

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After a Challenging First Year on Mars, InSight Shows Us that Mars is Seismically Active

In this artist's concept of NASA's InSight lander on Mars, layers of the planet's subsurface can be seen below and dust devils can be seen in the background. Image Credit: IPGP/Nicolas Sarter

The NASA and DLR InSight lander has been on Mars for over a year now. The mission has faced significant challenges getting its HP3 (Heat Flow and Physical Properties Package) into the subsurface, but the spacecraft’s other instruments are working as intended. Now, researchers have published six papers outlining some of the mission’s scientific results.

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There Are Winds Blowing On Pluto, Driven by Frozen Nitrogen

NASA's New Horizons spacecraft captured this image of Sputnik Planitia — a glacial expanse rich in nitrogen, carbon monoxide and methane ices — that forms the left lobe of a heart-shaped feature on Pluto’s surface. SwRI scientists studied the dwarf planet’s nitrogen and carbon monoxide composition to develop a new theory for its formation. Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute

Earth and Pluto don’t have much in common. Earth is a vibrant, living world, whereas Pluto is cold, distant and lifeless. But one thing they do have in common is nitrogen. Earth’s atmosphere is about 78% nitrogen, and Pluto’s primary atmospheric constituent is also nitrogen, although the exact percentage is unclear.

On Pluto, where the surface temperature is about 42 Kelvin (-231 Celsius) most of that nitrogen is frozen. A new study says that Pluto’s frozen nitrogen drives the planet’s winds, and shapes its feature surfaces.

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A Second Planet May Have been Found Orbiting Proxima Centauri! And it’s a Super Earth.

An artist's illustration of the Proxima Centauri system. Proxima b is on the left, while Proxima C is on the right. Image Credit: Lorenzo Santinelli

Astronomers have discovered another candidate exoplanet orbiting our neighbor, Proxima Centauri. A paper announcing these results was just published in the journal Science Advances. If confirmed, it will be the second exoplanet orbiting the star.

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How Long is a Day on Venus? Astronomers Make Their Best Measurement Yet

A radar image of the surface of Venus showing one of the surface features used to measure a revised value for the length of the Venusian day. Image Credit: Campbell et al., 2019

There’s a problem with Venus. We don’t know how fast it rotates. For a space-faring civilization like ours, that’s a problem.

Measuring the length of day, or rotation rate, of most bodies is pretty straightforward. Mark a prominent surface feature and time how long it takes to rotate 360 degrees. But Venus is blanketed in thick clouds. Those clouds give it its reflectivity, and make it bright and noticeable in the sky, but they make it hard to measure Venus’ day length.

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This Dried Up Riverbed Shows that Water Once Flowed on the Surface of Mars

This image from ESA’s Mars Express shows a dried-up river valley on Mars named Nirgal Vallis. Copyright ESA/DLR/FU Berlin, CC BY-SA 3.0 IGO

From some viewpoints, Mars is kind of like a skeleton of Earth. We can see that it had volcanoes, oceans, and rivers, but the volcanoes no longer fume and the water is all gone. A new image from the ESA’s Mars Express drives the point home.

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Io’s Largest Volcano, Loki, Erupts Every 500 Days. Any Day Now, It’ll Erupt Again.

This picture from Voyager 1 shows the volcano Loki on Jupiter’s moon Io. When this picture was taken, the main eruptive activity came from the lower left of the dark linear feature (perhaps a rift) in the center. Below is the "lava lake," a U-shaped dark area about 200 kilometers across. Credit: NASA/JPL

Jupiter’s moon Io is in stark contrast to the other three Galilean moons. While Callisto, Ganymede, and Europa all appear to have subsurface oceans, Io is a volcanic world, covered with more than 400 active volcanoes. In fact, Io is the most volcanically active body in the Solar System.

Io’s largest volcano is named Loki, after a God in Norse mythology. It’s the most active and most powerful volcano in the Solar System. Since 1979, we’ve known that it’s active and that it’s both continuous and variable. And since 2002, thanks to a research paper in the Geophysical Research Letters, we’ve known that it erupts regularly.

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Whoa. Lakes on Titan Might be the Craters from Massive Underground Explosions

This artist's concept of a lake at the north pole of Saturn's moon Titan illustrates raised rims and rampartlike features such as those seen by NASA's Cassini spacecraft around the moon's Winnipeg Lacus. Credit: NASA/JPL-Caltech

The Cassini spacecraft ended its mission to Saturn and its moons two years ago when it was sent plunging into Saturn to be destroyed. But after two years, scientists are still studying the data from the Cassini mission. A new paper based on Cassini data proposes a new explanation for how some lakes on Titan may have formed.

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