Sometimes I hear astronomy news that is cool, and sometimes I hear news that’s very cool… and sometimes I hear news where my reaction is, "That’s freaking insane!"

The latest news: scientists have used data tracking sound waves inside the Sun to see sunspots forming 60,000 kilometers (36,000 miles) deep in the Sun’s interior, fully two days before the spots erupt onto the surface!

That’s freaking insane.

OK, first, the video, then, the explanation.

[Make sure to set the resolution to 720p or 1080p to get the full effect.]

I love the last few seconds of that video; the rotation of the Sun sweeping the towering loops of magnetically-influenced plasma around to the limb is simply stunning.

So how does this all work? Sound waves.

Basically, inside the Sun, hot plasma (gas stripped of one or more electrons) rises and cooler plasma sinks. As it moves, it generates turbulence. This in turn creates acoustic waves — sounds — that travel through the Sun. As these waves move through the solar interior, regions with different densities make them speed up or slow down. The physics of this is pretty well understood, so by mapping how long it takes a ...