The ill-fated Russian Phobos-Grunt Mars probe reentered on Sunday at 1745 GMT (12:45 p.m. EST). Most of the surviving pieces reportedly fell into the Pacific Ocean.

About two months ago Phobos-Grunt was launched and should have been injected into a heliocentric transfer trajectory that would allow the spacecraft to escape Earth's gravity and travel around the sun on a path that was to end in a rendezvous with Mars. Unfortunately, its remains now reside some 1,250 km west of Wellington Island.

The Phobos-Grunt Mars spacecraft blasted off from Kazakhstan's Baikonur Cosmodrome in early November. The main goal was to capture some dirt from the surface of Phobos' and return.

Obviously, this was a very ambitious mission. If successful, Phobos-Grunt could have shed a great deal of light on the history of Mars and the solar system. Needless to say, this would have been a big morale booster for the Russian space program, which has suffered from three previous Mars mission failures since the late 1980s.

If all went well the unmanned probe would have reached Phobos, one of Mars' two moons, in late 2012. The next step would be to release a lander and allow it to touch down on Phobos a few months later.

This small moon, shaped like a 25-km long Idaho potato, is thought to be a former asteroid that was captured by Mars' gravity long ago. In fact, both moons are thought to be captured asteroids.

They were discovered in 1877 by Asaph Hall, and are named after the characters Phobos (panic/fear) and Deimos (terror/dread) who, in Greek mythology, accompanied their father Ares, god of war, into battle.

Upon reaching the surface of Phobos, soil samples were to be launched back to Earth and arrive sometime in 2014. Some instruments were to stay behind to carry out scientific observations.

Since asteroids are leftovers from the solar system's early days, i. e., primordial pieces that didn't get incorporated into planets. Scientists would be eager to sift through the samples. Unfortunately, this will all have to wait until next time.

Phobos-Grunt was also carrying several other payloads, including a capsule full of microbes prepared by the U.S. Planetary Society to investigate how life forms survive and behave on long flights through deep space.

The spacecraft also carried China's first Mars probe, a small spacecraft called Yinghuo 1 that was designed to separate from Phobos-Grunt and go into orbit around the Red Planet.