By Ian MacWilliam BBC, Almaty

Baikonur has an impressive record of firsts

Russia's main space centre, the Baikonur Cosmodrome, celebrates its 50th anniversary on Thursday.

The first orbiting Earth satellite and the first man in space took off from the centre, which is located in the steppes of neighbouring Kazakhstan.

The Russian President, Vladimir Putin, and his Kazakh counterpart, Nursultan Nazarbayev, visited the site to take part in the anniversary celebrations.

Baikonur is the world's oldest space-launching facility.

The Baikonur complex lies near the Aral Sea, deep in the arid wastes of the vast Kazakh steppe.

Soviet ruse

This remote, top-secret site was chosen in 1955 to be the nerve centre for the former Soviet Union's space programme.

The original Kazakh town of Baikonur it is named after in fact lies 400km (250miles) to the north-east. That was a Soviet ruse to confuse anyone looking for the cosmodrome's location.

The space centre notched up an impressive string of firsts in its early years. The first satellite to orbit the Earth, Sputnik 1, was launched from there in 1957.

Four years later, Yuri Gagarin blasted off to become the first man in space. The first woman in space and the first person to walk in space also took off from Baikonur.

When the USSR collapsed, many people thought it would mean the end for the cosmodrome, too.

But independent Kazakhstan agreed to lease the site to Russia. That lease now extends until 2050.

Moscow has been developing another space centre, Plesetsk, in the Russian far north. But its location makes it unfit for most commercial launches. Baikonur's facilities are now in regular demand for commercial satellite launches and to supply the International Space Station now orbiting the Earth.

Kazakhstan also has plans to launch its own satellites from the complex and Russia and Kazakhstan together are developing a more environmentally friendly launch facility.

Kazakhstan wants to reduce the pollution from rocket fuel and debris which often falls on its territory.