The red supergiant star, which is about 530 light-years from Earth, is among the brightest in the night sky. The star forms the shoulder of the constellation Orion (The Hunter). It’s also geriatric: Betelgeuse is nearing the end of its stellar life and will eventually explode in a supernova visible from Earth, though it may take another 100,000 years, according to a 2021 study. In late 2019, Betelgeuse’s light began to dim. By February 2020, it had lost two-thirds of its normal brightness as seen from Earth. Scientists studying the strange dimming concluded that the star itself would not go supernova directly, but that a giant dust cloud had obscured some of the star’s light. Now, scientists using the Hubble Space Telescope have revealed that this dust cloud was the result of a massive ejection from the star’s surface: A plume more than 1 million miles (1.6 million kilometers) wide may have risen from its interior star, producing the equivalent of a stellar earthquake, a shock that ejected a chunk of the star’s surface 400 million times larger than those typically seen in the sun’s coronal mass ejections, the team said in a paper published in the arXiv preprint database. accepted by The Astrophysical Journal for publication. “Betelgeuse continues to do some very unusual things right now; the interior is kind of bouncy,” said study author Andrea Dupree, associate director of the Harvard & Smithsonian Center for Astrophysics. This is uncharted territory in star science, Dupree said. “We’ve never seen a massive mass ejection of the surface of a star before,” he said. “We’re left with something going on that we don’t fully understand. It’s a completely new phenomenon that we can directly observe and resolve surface details with Hubble. We’re watching stellar evolution in real time.” The new research also incorporated information from a variety of other stellar observatories, including the STELLA Robotic Observatory in Spain’s Canary Islands and NASA’s Earth-orbiting STEREO-A spacecraft. By gathering different types of data, Dupree and her team were able to piece together a narrative of the explosion and its aftermath. The explosion ejected a chunk of the star’s lower atmosphere, the photosphere, leaving behind a cool spot that was further obscured by the dust cloud from the explosion. (NASA, ESA and E. Wheatley (STScI)) Above: In the first two panels, as seen in ultraviolet light with the Hubble Space Telescope, a bright, hot mass of plasma is ejected from the emergence of a giant convection cell on the star’s surface. In panel three, the outflowing, ejected gas rapidly expands outward. It cools to form a huge cloud of dark dust grains. The final panel reveals the massive dust cloud that blocks light (as seen from Earth) from a quarter of the star’s surface. The piece of photosphere was several times the mass of Earth’s moon, according to a NASA statement. This cool spot and dust cloud explain why Betelgeuse’s light has dimmed. The star is still feeling the reverberations, the researchers found. Before the explosion, Betelgeuse had a pulsating pattern, waxing and waning on a 400-day cycle. That cycle is now gone, at least temporarily. It’s possible that transport cells inside the star are still slipping, disrupting this pattern, the researchers found. The star’s outer atmosphere may have returned to normal, but its surface may still be moving like Jell-O, according to NASA’s Hubblesite. The explosion is not proof that Betelgeuse will go supernova soon, the researchers said, but it does show how old stars are losing mass. If Betelgeuse eventually dies in a stellar explosion, the light will be visible during the day from Earth, but the star is too far away to have any other effects on our planet. Related Content: How long do stars live? Red supergiants “dance” because they have too much gas 15 unforgettable pictures of stars This article was originally published by Live Science. Read the original article here.
