You know those odd features in some SDSS images that look like intergalactic traffic lights?
They aren’t intergalactic at all: they’re asteroids on the move in our own solar system. They move slowly compared to satellite trails (which look more like #spacelasers), but they often move quickly enough that they’ve shifted noticeably between the red, green, and blue exposures that make up the images in SDSS/Galaxy Zoo. When the images from each filter are aligned and combined, the moving asteroid dots its way colorfully across part of the image.
These objects are a source of intense study for some astronomers and planetary scientists, and the SDSS Moving Object Catalog gives the properties of over 100,000 of them. Planetary astronomer Alex Parker, who studies asteroids, has made a video showing their orbits.
I find their orbits mesmerizing, and there’s quite a lot of science in there too, with the relative sizes illustrated by the point sizes, and colors representing different asteroid compositions and families. There’s more information at the Vimeo page (and thanks to Amanda Bauer for posting the video on her awesome blog).
One of the most common questions we receive about asteroids from Galaxy Zoo volunteers is whether there will ever be a citizen science project to find them. So far, as the catalog linked above shows, the answer has been that computers are pretty good at finding asteroids, so there hasn’t been quite the need for your clicks… yet. There are some asteroids that are a little more difficult to spot, and those we’d really like to spot are quite rare, so stay tuned for a different answer to the question in the future. And in the meantime, enjoy the very cool show provided by all those little traffic lights traversing their way around our solar system.
Way back in August I gave a evening (public) plenary talk about “The Zoo of Galaxies” at the 28th General Assembly of the International Astronomical Union. I wrote a couple of blog posts about it at the time (here and a bit more here). Just this week I got word that the video is now available, so here it is:
To go with this I have also posted the “proceedings” (a write-up based on my talks) which will be appearing in the 16th Volume of “Highlights of Astronomy”. This is available on the arxiv. It’s not supposed to be a transcript as such, but if you watch both the video and read this I think you’ll see they’re quite similar.