The European Space Agency has launched a satellite it hopes will produce the most accurate three-dimensional map of our part of the Milky Way galaxy.
The agency said the Gaia satellite lifted off into space aboard a Russian-made Soyuz carrier system from French Guiana.
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 a billion stars in Earth's galactic neighbourhood.
Gaia will also use its 1,000-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.