19 December 2013 ESA PR 44-2013: ESA’s Gaia mission blasted off this morning on a Soyuz rocket from Europe’s Spaceport in Kourou, French Guiana, on its exciting mission to study a billion suns.
Gaia is destined to create the most accurate map yet of the Milky Way. By making accurate measurements of the positions and motions of 1% of the total population of roughly 100 billion stars, it will answer questions about the origin and evolution of our home Galaxy.
The Soyuz launcher, operated by Arianespace, lifted off at 09:12 GMT (10:12 CET). About ten minutes later, after separation of the first three stages, the Fregat upper stage ignited, delivering Gaia into a temporary parking orbit at an altitude of 175 km.
Gaia, a satellite of the European Space Agency (ESA), is launched tomorrow, 19 December. It will take a census of a billion stars to create the most complete 3D map of the Milky Way ever done. Launch is planned to occur at 10.12 a.m. (local time in mainland Spain) from Europe’s spaceport in Kourou (French Guiana). Scientists and engineers from the University of Barcelona (UB) have remarkably collaborated in the mission.
A group of researchers from UB, the Barcelona Team, has developed the Gaia Mission App, which allows discovering scientific and technical details of the mission and keeps users updated on satellite’s operations from 19 December. App is available in English, Spanish and Catalan.
Gaia is considered ESA’s cornerstone mission not only for its ability to revolution future astrophysics —thanks to the unprecedented accuracy of its astrometric observations—, but also for the technological challenge it means. In addition, the project constitutes the maximum exponent of a technology that places Europe in a leading position in the field of astrometry.
Among the hundred billion stars which can be observed in the Milky Way, there is a group of stars, the so-named ultra-cool dwarfs, defined as stars with a temperature below 2500 K, which includes ultra-cool dwarfs and brown dwarfs. It is a really interesting group: they are the most ancient objects in our Galaxy and, therefore, they can provide information about its primitive chemical composition. This is one of the objectives of Gaia mission which will be launched at the end of 2013 by the European Space Agency.
When observing them, they seem quite similar, but there are clear differences between brown dwarfs and ultra-cool dwarfs: brown dwarfs do not reach the temperature they need to produce the nuclear reactions which characterize ultra-cool dwarfs. It could be said that brown dwarfs are failed stars because they lack mass.
A study published on the journal Astronomy & Astrophysics, led by the National University of Distance Education (UNED) and in which researchers from the Institute of Cosmos Sciences of the UB (ICCUB) participated, has developed a method that will allow Gaia to detect tens of ultra-cool dwarfs in the Milky Way. The method to estimate physical parameters of these objects, such as temperature or gravity, has also been validated. Researchers have used data mining techniques to make estimations taking into account the parameters that Gaia can measure and its design characteristics.
ESA’s Gaia mission to survey a billion stars has passed a gruelling test to prove it can withstand the extreme temperatures it will experience in space when it is launched next year.
After arrival at its working position some 1.5 million km from Earth, Gaia will operate at a temperature of –110°C, shielded from the heat of the Sun by a giant shade attached to the spacecraft to keep its instruments in permanent shadow.
The focus of the most recent test was Gaia’s service module, which houses electronic units to run the science instruments, as well as the units that provide the spacecraft resources, such as thermal control, propulsion, communication, and attitude and orbit control.