A Russian Progress space cargo ship boosted the orbit of the International Space Station by two kilometers Thursday morning, the Russian space agency said.

The Progress M-21M's engines burned for almost ten minutes to raise the station to a more optimal orbit ahead of the arrival of a Soyuz spacecraft later this month. The Soyuz TMA-12M will be carrying astronauts to begin the first year-long mission aboard the station, double the length of previous stays.

Boost maneuvers are periodically performed as the station's orbit naturally decays due to friction with trace quantities of gases in the rarified atmosphere present in low earth orbit.

Source: RIA Novosti