Falling satellite to hit Earth

A 2,000-pound European satellite is expected to re-enter Earth's atmosphere within hours, its controllers announced Sunday as the craft circled gradually downward.

The Gravity Field and Steady-State Ocean Circulation Explorer -- a European Space Agency satellite known shorthand as GOCE -- had fallen to an altitude of about 122 kilometers (75 miles) by Sunday night, the ESA reported. It's now expected to plunge into the atmosphere and break up sometime before 8 p.m. ET, the ESA said.

"The most probable re-entry area lies on a descending orbit pass that mainly runs across the Pacific and the Indian Ocean," the agency reported. Controllers have all but ruled out any chance that the spacecraft would come down over Europe, it said.

GOCE's orbit can be tracked via an ESA website.

The 5-meter (16-foot) satellite was launched in 2009 to map variations in the Earth's gravity in 3-D, provide ocean circulation patterns and make other measurements. Powered by solar panels and not-your-average lithium-ion battery, it lasted more than three times its expected lifespan before running out of juice on October 21.

In March 2011, the ESA added another role -- as the "first seismometer in orbit" -- when GOCE detected sound waves from the massive earthquake that struck Japan.

 Re-entry is now likely over the Pacific or Indian oceans, ESA reports