"Reconstructing the XUV Spectra of Active Sun-like Stars Using Solar Scaling Relations with Magnetic Flux" Kosuke Namekata, Shin Toriumi, Vladimir S. "Detection of a high-velocity prominence eruption leading to a CME associated with a superflare on the RS CVn-type star V1355 Orionis" Shun Inoue, Hiroyuki Maehara, Yuta Notsu, Kosuke Namekata, Satoshi Honda, Keiichi Namizaki, Daisaku Nogami, Kazunari Shibata 2023, ApJ in press ADS arXiv:2301.13453 "Magnetic activity variability from Hα line intensive monitoring for two F-type stars having a hot-Jupiter, τ Bootis A and υ Andromedae A" Sanghee Lee, Yuta Notsu, Bun'ei Sato 2023, PASJ in press ADS arXiv: 2302.02135 Application to TESS data for M-dwarf flare stars, AU Microscopii, YZ Canis Minoris, and EV Lacertae" Kai Ikuta, Kosuke Namekata, Yuta Notsu, Hiroyuki Maehara, Soshi Okamoto, Satoshi Honda, Daisaku Nogami, Kazunari Shibata 2023, ApJ in press, ADS arXiv:2302.09249 "Now, it's a much bigger problem because of our electronics."Ĭo-authors on the recent study include researchers from Kyoto University, the National Astronomical Observatory of Japan, University of Hyogo, University of Washington and Leiden University."Starspot mapping with adaptive parallel tempering. People may have seen a large aurora," Notsu said. "If a superflare occurred 1,000 years ago, it was probably no big problem. Still, that could give humans time to prepare, protecting electronics on the ground and in orbit from radiation in space. But he said that it's a matter of when, not if. Notsu can't be sure when the next big solar light show is due to hit Earth. The group published its latest results in May in The Astrophysical Journal. "For the sun, it's once every few thousand years on average." "Young stars have superflares once every week or so," Notsu said. But older stars like our sun, now a respectable 4.6 billion years old, aren't off the hook. Based on the team's calculations, younger stars tend to produce the most superflares. The researchers then subjected those rare events to a rigorous statistical analysis. Over a series of studies, the group used those instruments to narrow down a list of superflares that had come from 43 stars that resembled our sun. To find out, Notsu and an international team of researchers turned to data from the European Space Agency's Gaia spacecraft and from the Apache Point Observatory in New Mexico. "But we didn't know if such large flares occur on the modern sun with very low frequency." "When our sun was young, it was very active because it rotated very fast and probably generated more powerful flares," said Notsu, also of the National Solar Observatory in Boulder. But what the Kepler data was showing seemed to be much bigger, on the order of hundreds to thousands of times more powerful than the largest flare ever recorded with modern instruments on Earth.Īnd that raised an obvious question: Could a superflare also occur on our own sun? Notsu explained that normal-sized flares are common on the sun. Researchers dubbed those humungous bursts of energy "superflares." In rare events, the light from distant stars seemed to get suddenly, and momentarily, brighter. But it also found something odd about those stars themselves. The NASA spacecraft, launched in 2009, seeks out planets circling stars far from Earth. Scientists first discovered this phenomenon from an unlikely source: the Kepler Space Telescope. "But there is some possibility that we could experience such an event in the next 100 years or so." "Our study shows that superflares are rare events," said Notsu, a researcher in CU Boulder's Laboratory for Atmospheric and Space Physics. Notsu presented his research at a press briefing at the 234th meeting of the American Astronomical Society in St. Such a blast could disrupt electronics across the globe, causing widespread black outs and shorting out communication satellites in orbit. If a superflare erupted from the sun, he said, Earth would likely sit in the path of a wave of high-energy radiation. The results should be a wake-up call for life on our planet, said Yuta Notsu, the lead author of the study and a visiting researcher at CU Boulder. Now, new research shows with more confidence than ever before that superflares can occur on older, quieter stars like our own - albeit more rarely, or about once every few thousand years. Until recently, researchers assumed that such explosions occurred mostly on stars that, unlike Earth's, were young and active. These events occur when stars, for reasons that scientists still don't understand, eject huge bursts of energy that can be seen from hundreds of light years away.
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