Brown dwarfs are relatively cool, dim objects that are too massive to be planets, yet they are too small to sustain hydrogen fusion reactions. By observing a brown dwarf 20 light-years away, researchers have found another feature that makes these so-called failed stars more like supersized planets — they host powerful aurorae near their magnetic poles.
Like graffiti sprayed by an unknown artist, unexplained narrow, arc-shaped, reddish streaks are visible on the surface of Saturn’s icy moon Tethys in new, enhanced-colour images from NASA’s Cassini spacecraft. The red arcs are among the most unusual colour features on Saturn’s moons to be revealed by Cassini’s cameras.
Colourful new maps of Ceres, based on data from NASA’s Dawn spacecraft, showcase a diverse topography, with height differences between crater bottoms and mountain peaks as great as 9 miles (15 kilometres). Some of these craters and other features now have official names, inspired by spirits and deities relating to agriculture from a variety of cultures.
Astronomers have long known that powerful cosmic winds can sometimes blow through galaxies, sweeping out interstellar material and stopping future star formation. A Yale University analysis of one such event in a nearby galaxy provides an unprecedented look at the process, offering a clearer snapshot of how it happens.
NASA’s New Horizons mission has found evidence of exotic ices flowing across Pluto’s surface, at the left edge of its bright heart-shaped area. New close-up images from the spacecraft’s Long-Range Reconnaissance Imager (LORRI) reveal signs of recent geologic activity, something scientists hoped to find but didn’t expect.
A ripple in the outskirts of the Milky Way led Rochester Institute of Technology astrophysicist Sukanya Chakrabarti to a previously undetected dwarf galaxy hidden under a veil of dark matter. Now Chakrabarti is refining her technique to uncover dwarf galaxies and understand dark matter by simulating the evolutionary histories of galactic discs and their satellite populations.
A fast-moving pulsar appears to have punched a hole in a disc of gas around its companion star and launched a fragment of the disc outward at a speed of about 4 million miles per hour. NASA’s Chandra X-ray Observatory is tracking this cosmic clump, which appears to be picking up speed as it moves out.
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