On November 8, an asteroid 400 meters across will pass by the Earth, missing us by the very comfortable margin of about 320,000 kilometers (200,000 miles). Named 2005 YU55, it’s been known for some time that this pass will occur, and astronomers are jumping on the chance to observe it.
First off, it’s no danger to Earth right now. It’s what’s called a Potentially Hazardous Asteroid because its orbit intersects ours, but observations have shown it won’t be a danger to Earth for at least a century, and probably much more. There’s been some scare-mongering about it over the past few months, but as usual that’s all baloney. This rock will pass us safely, sailing on into the night.
But given that this is close in astronomical terms, astronomers will be observing it carefully. There are plans to use NASA’s Deep Space Network of radio telescopes, as well as the Arecibo ‘scope in Puerto Rico (which was used to make the image above back in April 2010). They’ll be able to see features on this rock as small as two meters across, which means we’ll actually get some interesting images of it, I hope. I’ll post those as soon as I see ’em (which will be after November 8).
It’ll only get to a magnitude of about 11 — only 1/100th as bright as the faintest star you can see with your unaided eye — so you’ll need a decent-sized (12.5 cm at least) telescope to see it. 320,000 km is 3/4 of the way to the Moon, and this asteroid is small and very dark. Observing it will be tough, but you can get more info on how to do it at the Minor Planet site and on The Minor Planet Bulletin (PDF).
When I was a kid, asteroids were not much more than mysterious points of light, but now we have the technology to see them in detail from the ground, and even send space probes to get good, close looks at them! And, of course, the technology to spread those images and information as quickly as the speed of light around the globe. Sometimes that’s used to spread misinformation, but it also can be used to show people what a cool place we live in. I prefer the latter.