Tiny Solar System
Most of the known planets in other solar systems are giants. They're much heavier than Jupiter, the giant of our own solar system, and probably a good bit bigger, too. But a system of little planets may be taking shape around a brown dwarf -- an object that's no bigger than some of these giant planets.
The system is in the constellation Chamaeleon. It's known by a long catalog name, which we'll shorten to Chamaeleon 1109. A team led by Penn State astronomer Kevin Luman studied it with Spitzer Space Telescope, which detected the infrared energy of this warm but faint object.
A brown dwarf is a "failed star" -- a ball of gas that's not massive enough to ignite the reactions that power true stars. 1109 is only about eight times as massive as Jupiter. That means it's similar to some of the giant planets that have been discovered around true stars. It's not classified as a planet, though, because it formed in the same way that stars form.
Spitzer and other telescopes studied a disk of dust grains that encircles 1109 -- possibly raw material for planets. The brown dwarf is only about two million years old, though, so there probably hasn't been enough time for planets to form.
There isn't much material in the disk, so any planets that take shape are likely to be similar to Mercury or Pluto, the smallest planets in the solar system -- tiny worlds for a tiny solar system.
Script by Damond Benningfield, Copyright 2005
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