Space Wobble Indicates Planet in Big Dipper

UC Berkeley astronomers have found a Jupiter-sized planet orbiting a nearby star at a distance comparable to Jupiter’s orbit around our sun. The star, 47 Ursae Majoris in the Big Dipper, is 51 light-years from Earth and was already known to have an orbiting planet 2.5 times the size of Jupiter.

The discovery, which will be reported in a future issue of Astrophysical Journal, was made possible by new measurement techniques that allowed Debra Fischer and her colleagues to detect a minute wobble in the motion of 47 Ursae Majoris. The wobble is caused by the gravitational attraction of the planet. Such a relatively small planet that far from a star--3.7 times the distance from the Earth to the sun--has never before been detected. The feat required 13 years of observations.

*

Compiled by Times medical writer Thomas H. Maugh II