What's All This, Then?

Scientists in Hawaii (!) recently photographed a star with spiral arms through the Subaru telescope (no telling what we'll see when the Volkswagen or Lexus telescopes become operational, snicker snicker).

This is weird because stars are usually orbited by one of three things: planets, like our sun; a big disk-shaped cloud of gas that will one day turn into planets; or nothing. Although some images of stars before have shown different clumps and thicknesses in those dust disks, this is the clearest image yet of one of them that isn't just a diffused field of dust.

The astronomers who photographed the star, SAO 206462, say the spiral arms inside the disc may mean that it is much farther along in its process of planet formation. The current main theory for how planets form is that when the massive center of one of those dust disks kindles into a star and begins shining, the rest of the disk will eventually coalesce into one or more planets. The gravity and radiation of the star help eddies and swirls form in the cloud, and as more and more particles of dust group up in them, their gravitational pull on nearby dust increases. Eventually they form small rocky planets like Earth or large gas giants like Jupiter. The thought is that the spirals might be one of the steps along the way from dust cloud to planet.

Although SAO 206462 is only four hundred light-years away and so relatively close by in interstellar distances, the process of planetary formation takes billions of years, so it's not likely we'll see the outcome even though we're just around the corner from it.

Still plenty cool, though.