The probe disintegrated during reentry on Sunday, January 15

Jan 16, 2012 08:13 GMT  ·  By
This is an artist's rendition of how the Phobos-Grunt spacecraft may have looked like during atmospheric reentry
   This is an artist's rendition of how the Phobos-Grunt spacecraft may have looked like during atmospheric reentry

Officials with the Russian Federal Space Agency (RosCosmos) confirm that their Phobos-Grunt space probe disintegrated upon atmospheric reentry yesterday, January 15. The spacecraft, originally bound for the Martian moon Phobos, fell back to Earth due to a glitch in its main engine.

Launched on November 8, the Russian mission was supposed to reach low Earth orbit, and then fire up its main thruster. The maneuver was to insert it on the correct path towards the Red Planet. However, engine ignition failed for yet-unknown reasons, and the probe became trapped in a decaying orbit.

At the time, experts estimated that this would eventually lead to an atmospheric reentry, since the probe was slowly beginning to enter an unsustainable orbital track. They estimated that Phobos-Grunt would make its way back into Earth's atmosphere by mid-January, and they weren't even a day off in their predictions.

News reports indicate that the spacecraft reentered our planet's atmosphere at around 1745 GMT, and that it eventually crashed into the Pacific Ocean, without causing any damage. That was a big concern for the Russians, since the spacecraft weighs around 14.5 tons.

Russian officials told the Ria Novosti news agency that the probe disintegrated off the coast of Chile, without making any splash on land. “Phobos-Grunt fragments have crashed down in the Pacific Ocean,” explained Russian Defense Ministry official Alexei Zolotukhin, as quoted by Space.

One thing that authorities don't know is how many pieces of the former spacecraft survived, or how large those components are. It is estimated that around 20 or 30 such parts survived the scorching temperatures of reentry, and made their way into the waves.

But RosCosmos experts are at ease knowing that at least Phobos-Grunt's large tanks of highly-toxic fuels burnt up high in the Earth's atmosphere. There was a genuine concern that the chemicals would spread into soils and groundwater reserves, were the spacecraft to fall on the ground.

“They did acknowledge early on that the [fuel] tanks are made of aluminum. Aluminum rarely survives re-entry, so there's no reason to really doubt them,” explains NASA expert Nick Johnson. He holds an appointment as chief scientist at the Johnson Space Center Orbital Debris Program Office, in Houston.

The Russians also revealed the presence of 10 micrograms of radioactive Cobalt-57 aboard the former spacecraft, but explained that there is little risk of this material contaminating the ocean to any discernible level.