The European Space Agency has launched a satellite that it hopes will produce the most accurate three-dimensional map of our part of the Milky Way galaxy.
The agency says its Gaia satellite was lifted into space aboard a Russian-made Soyuz carrier system from French Guiana at 6.12am on Thursday (local time).
Gaia is heading to a stable orbit called the Lagrange 2 point where Earth will shield it from the Sun.
Once it arrives, the satellite will begin its mission to survey some 1 billion stars in Earth's galactic neighbourhood.
Gaia will also use its 1000-megapixel camera to hunt for planets, asteroids and comets beyond our Solar System, and test a key part of Albert Einstein's General Theory of Relativity.
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