Astronomy Picture of the Day

Explanation: Is our Solar System unique? The discovery of a Jupiter-like planet in a Jupiter-like orbit around nearby Sun-like star 55 Cancri, announced yesterday, gives a new indication that planetary systems similar to our Solar System likely exist elsewhere. The planet, discovered by G. Marcy (UC Berkeley) and collaborators, is one of two new planets found around 55 Cancri -- in 1997 a Jupiter-massed planet was found orbiting very close in. The finding involved noting subtle changes in the speed of the star caused by its orbiting planets. The above drawing depicts what this planet might look like, complete with a hypothetical moon. The star 55 Cancri, only 40 light-years distant, is visible with binoculars towards the constellation of Cancer.