What happens if the Russian spacecraft falls to earth?

If the 12 tons of fuel of the Phobos Grunt ship does not freeze, it is capable of causing damage when dropped.

Phobos Grunt spacecraft was launched into space on November 8 to sample soil on Mars's Phobos satellite. After separating from the boosters on the earth's low orbit, the two ships' engines did not operate, making the ship stranded. The Russian Federal Space Agency (Roskomos) predicts their ship may fall to Earth in early January next year.

Phobos Grunt's volume is 13.2 tons, of which the ship's fuel volume is up to 12 tons. The consequences that Phobos Grunt may cause during the fall depend on whether its fuel exists in a liquid or solid state at the time of fall, the AP said.

Nicholas Johnson, head of NASA's space garbage monitoring division, said that the possibility of fuel still being higher in liquid form.

But James Oberg, a space consultant who worked at NASA, is concerned that the fuel on the Phobos Grunt vessel will turn to ice in the next two weeks. If that prediction occurs, the Russian spacecraft will become the most dangerous cosmic garbage falling to the globe.

If the fuel freezes, it may not burn when the ship is rubbing against the atmosphere and causing trouble when touching the ground.

In 2008, concerned about the dangers of a frozen hydrazine fuel tank on a 'dead' spy satellite that could cause a disaster if the satellite falls, the US government ordered the navy to shoot the satellite with rocket.

Many objects are heavier than the Phobos Grunt that once fell to the earth - like the US Skylab satellite and Russia's Mir space station.

Phobos Grunt was the first spacecraft launched into a planet since the accident of the Mars-96 ship 15 years ago. Mars-96 fell into the Andes Mountains in South America shortly after launch. Oberg said that if the Phobos Grunt spacecraft fell, it could cause greater damage than the Mars-96 spacecraft. Even so, the probability of the ship's debris falling on people is very small.