On April 19, 2010, NASA’s newly-launched Solar Dynamics Observatory caught a massive eruption on the Sun, called a prominence, as it blasted millions of tons of 60,000 K (100,000° F) gas off the surface of the Sun. Check out this amazing footage as the material blows upward, then rains back down onto the Sun’s surface.
Holy Haleakala! If you watch carefully, you can see little hot spots flash as the gas hits the Sun again. At about 31 seconds, a thin streamer comes screaming back down; look carefully where it hits and you’ll see those spots. This animation is actually about four hours worth of images strung together. Note the scale of this scene: it shows a region about 100,000 km (60,000 miles) across! The Earth would easily fit under the arch of this rising gas.
Oh– before you ask, that dark hair-like thing is a piece of dust or some other detritus in the SDO camera. That’s aggravating, but I’m hoping the engineers will figure out a way of getting rid of it or at least minimizing its influence.
Prominences like this have been seen for decades, but never in this much detail. And even though SDO has only been flying for a few weeks, it’s already solved one mystery: why the rain of gas moves more slowly than expected as it rains back down. You can’t see it in this video (but you can on this page about SDO) but there is a layer of much hotter gas near the surface of the Sun. This gas, at about 1,000,000 Kelvin (1.7 million° F) cushions the fall of the rain, slowing it down. SDO’s high resolution and ability to measure the temperature of the gas allows astronomers to understand this phenomenon for the first time.
SDO is extremely cool, and will be providing solar astronomers with more data than they can possibly handle for decades. But that’s good! It’s always nice to have more data than less. The Sun is fiendishly complex and difficult to understand in detail, so SDO will be an incredibly useful tool to help astronomers figure out what’s what.
After all: there not be anything new under the Sun, but there are always new ways of looking at it.