Russia has launched a satellite needed to create its own global navigation system, intended to rival America's Global Positioning System (GPS).
The Glonass-K satellite was carried into orbit on a Soyuz rocket from a cosmodrome in northern Russia.
In December, an attempt to put the final three satellites into space failed when they crashed into the sea.
More launches are planned with the aim of finishing the system this year.
'Sovereignty'
The Russian prime minister, Vladimir Putin, has said the Glonass system will give the country satellite navigation sovereignty.
http://www.bbc.co.uk/news/world-europe-12587238
Note:26 February 2011 Last updated at 12:46 GMT