One day, a long long long time from now, the Sun will expand to many times its current size, engulfing the inner planets, including our own Earth, vaporizing our atmosphere and rocks and trees and cute baby deer. What will that look like? Some astronomers at Washington University St. Louis decided to find out.
For all of modern astronomy, we were pretty damn certain about the shape of the sun. It’s a giant ball of hot plasma and gas and magnetism, so it made sense that in test after test, it was an ever-changing, wobbly undulating thing, where the exact shape was never the same. But we were wrong. It’s a near perfect sphere, slightly flat near the poles, but otherwise almost perfectly round.
Normally, when anything crashes into a star, you can pretty much hang it up for that whatever it is. So when astronomers saw a comet named Lovejoy plunge into the Sun’s corona, the assumption was that was the end of the comet.. until the comet came out the other side of the Sun. A giant furnace, where even atoms are stripped down to their base components and yet somehow a comet survived.
First off, to be clear, solar flares do not pose any threat to life on Earth. However, a massive solar flare could, and has, disrupted communications by knocking out or disorienting satellites. But ahead of the solar maximum in 2013 or 2014, sun-watchers have been observing the build-up of what could be an incredibly massive flare that could be headed our way.
Solar storms hit the Earth on a fairly regular basis, but here on terra firma, we can’t really see them when we’re in the middle of them. But now with the STEREO probe way out in space studying the Sun, it was able to turn its eye back onto the Earth to watch our tiny blue dot get completely engulfed in a massive solar storm.
Over the last century, we’ve been able to use all sorts of modern technology like “lasers” to very precisely measure the distance from the Earth to the Sun, also known as one astronomical unit (AU). And in measuring this distance precisely, we’ve noticed something very strange— the Earth and the Sun are moving away from each other very very slowly, at the rate of about 15 cm per year. But why?