A Russian scientific probe that was meant to visit a Martian moon but never made it out of Earth's orbit crashed into the Pacific Ocean about 700 miles west of Chile on Sunday, a Russian military spokesman said.
The Phobos-Grunt spacecraft had been circling Earth since shortly after its launch on Nov. 9, losing a few miles of altitude each day until it fell into the atmosphere.
The 13-ton ship was one of the heaviest manmade objects yet to make an uncontrolled plunge back to Earth, though most of its weight was fuel and probably burned up during re-entry.
The vehicle could have crashed almost anywhere, but as with other falling space junk, the odds were that it would hit an ocean.
Col. Alexei Zolotukhin, a spokesman for Russia's Aerospace Defense Troops, told the Interfax news agency that the spacecraft, which broke up in the atmosphere, hit the water in fragments about 12:45 p.m. Eastern time.
The crash cut short what was to have been an ambitious 2 1/2-year voyage to Phobos, one of Mars' two small moons, and back again.
The mission to retrieve the first soil sample from a Martian moon would have been a milestone for Russia. The Phobos-Grunt's lander was equipped with a small shovel to put about 8 ounces of dirt into a tiny capsule to return to Earth.
The mission started with a successful launch to Earth's orbit, but the engine meant to boost the spacecraft out of orbit and on its way to Mars failed to fire, and scientists were unable to correct the problem.
Speculating last week about possible causes of the failure, the director of the Russian space agency said that Phobos-Grunt might have been hit by an antisatellite weapon from an unspecified source while over the Western Hemisphere and out of direct observation from Russia. He also mentioned possible technical flaws.