Wednesday, September 17, 2008

See You (22,500 years) Later, Alligator!

Here is the discovery of a cosmic oddball with the not so poetic name of SQ372. The minor planet was discovered by the Sloan Digital Sky Survey (SDSS)about 2 billion miles from the Sun (about the distance of Neptune). The unusual thing about this little guy is that its orbit is elliptical...very elliptical. It takes 22,500 years to complete one orbit and ends up about 150 billion miles away at its farthest point.

They were not even looking for asteroids or comets but supernova. The SDSS was scanning the same area of the sky every clear night looking for supernova. When you get this type of data, you can also find moving objects, but it takes a different computer program to find them. So they wrote the program and you can see the discovery images in the animation below.
Doesn't exactly jump out at you, does it? This guy is probably less than 30-60 miles across and has a composition similar to a comet. Unlike comets, it never gets close enough to the Sun to form a tail.

The significance of this discovery is that it is an object that appears to have originated between the Kuiper belt (a collection of icy bodies between Neptune and about 5 billion miles from the Sun) and the Oort Cloud (which should lie about a trillion miles from the Sun). Astronomers have dubbed this area the Inner Oort cloud (not exactly a creative name) and its existence is still controversial. However, a previously discovered body named Sedna (it was big enough to get a name) and now this guy are starting to provide a little more evidence for the Inner Oort Cloud model of the solar system.

This discovery is a nice example of science in action. Observations are made, predictions are made and tested by more observations and experiments. Ideas are revised based on new observations. I am looking forward to more discoveries as we try to piece together the mysteries of the outer solar system.

2 comments:

kkdither said...

They are calling that a planet? Pluto must be ticked...

hale-bopp said...

Minor planet...VERY minor planet :)