the total cost of the mission would come to 740 million euros -LRB- $1.02 billion -RRB- when the expense of the launch and running the mission for its projected five-year lifetime are included. If successful, Gaia will add to the knowledge gained from NASA's Hubble Space Telescope, which is still in operation, and ESA's Hipparcos satellite, which gathered data until 1993. Hubble spots azure planet where it may rain glass The value of putting a billion-pixel camera into space has been championed by Robert Massey from the UK's Royal Astronomical Society. Gaia is an amazingly ambitious mission, he said. Until now astronomers have relied on very indirect methods to gauge the distance to all but the nearest stars, meaning that the foundation on which we build a map of the universe is surprisingly weak. Building on the work of the pioneering Hipparcos satellite that mapped the stellar neighbourhood in the 1990s, Gaia will be used to carry out work analogous to the cartographers who surveyed the Earth in the 19th and 20th centuries, building up the first accurate charts of the cosmos and helping us better understand the structure, history and fate of the galaxy we live in. One of Gaia's objectives is to help in the hunt for exoplanets -- new worlds beyond our own solar system. NASA's Kepler mission has so far confirmed the existence of 167 exoplanets with hundreds more being