The prosaically named object CFBDSIR 2149-0403 is an oddball. Literally. Is it a rogue planet ejected from its birth system, or a brown dwarf lurking near a star cluster? New observations have narrowed, but not quite solved, the mystery.
Exoplanets are planets orbiting other stars. It's widely claimed that the official definition of "planet" excludes exoplanets. There are two problems with this: It's wrong, and it's impossible to define "planet" anyway.
Astronomers have found an astonishing seven Earth-sized planets orbiting a single star just 40 light-years away! This is one of the most common kinds of stars in the galaxy, implying systems like this may outnumber our own.
Earth is pretty good at supporting life, but according to a new estimate of what constitues a planetary "habitable zone," it looks like our planet (and perhaps many others) is only barely in the right place.
A few months ago, scientists predicted that it would take two more years until we found another habitable planet somewhere out there. Well, one team of astronomers may have just shattered that prediction, because the planet they just found looks very promising and very Earth-like.
With hundreds of planets now detected in orbit around other stars, and more of them displaying possible Earth-like characteristics, scientists say that 2013 will be the year we finally discover another Earth.