Nearby star’s midlife crisis illuminates the future of our own Sun

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https://www.science.org/content/article/nearby-star-midlife-crisis-suggests-our-own-sun-may-lose-its-spots-again-decades

By Zack Savitsky, Science Magazine. 

Excerpt: Long magnetic lull on star mimics the Maunder Minimum, when the Sun’s spots largely disappeared 400 years ago. Soon after European astronomers developed the first telescopes at the start of the 17th century, they observed dark spots speckling the Sun’s surface. They also handed their modern successors a mystery. From about 1645 to 1715, the spots, now known to be indicators of solar activity, all but disappeared. Gathering sunspot counts and other historical observations, astronomer John Eddy concluded nearly 50 years ago that the Sun had essentially taken a 70-year nap, which he called the Maunder Minimum after an astronomer couple who had previously studied it. Now, it appears the Sun is not the only star that takes long naps. By building a decades-long record of observations of a few dozen stars at specific wavelengths that trace stellar activity, a team of astronomers has identified another star going through its own Maunder Minimum period. ...The finding, reported in a preprint last month on arXiv, could help explain what triggered the Sun’s strange behavior 400 years ago and suggests more such episodes are likely. ...van Saders says...that such events are an occasional symptom of a critical transition in the magnetic field of Sun-like stars about halfway through their lifetime—a midlife crisis of sorts. Some astronomers speculate that the Sun’s transition helped favor the emergence of life on Earth.... Scientists have known for decades that our Sun’s activity surges and ebbs on a roughly 11-year cycle, which corresponds to how often its magnetic poles flip their orientation. During a solar maximum, sunspots proliferate, marking weak points in the magnetic field, where plasma from the Sun’s atmosphere can lash out in violent loops. Astronomers have spotted young Sun-like stars with similar cycles, and older ones that have totally stable activity. But no one had spotted a cycling star suddenly turning flat.…

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