Will the Next Space-Weather Season Be Stormy or Fair?

As another 11-year cycle of solar activity begins, scientists debate how violent our stellar friend is likely to be.

The big news about the sun is that there is no big news. We are blessed, astronomers like to say, to be living next to a “boring star.” But the inhabitants (if there are any) of the planets orbiting the neighboring star Proxima Centauri, only 4.2 light-years away, are less fortunate. In April astronomers announced that a massive flare had erupted from its surface in 2019. For seven seconds, as a battery of telescopes on Earth and in space watched, the little star had increased its output of ultraviolet radiation 14,000-fold, in one of the most violent such flares ever seen in our galaxy. This was more than serious sunburn territory. “A human being on this planet would have a bad time,” said Meredith MacGregor, an astronomy professor at the University of Colorado who led the worldwide observing effort.