It will remain in place until around 3 years after the end of the mission, up to the release of the final product: the Gaia catalogue. DPAC brings together more than 450 specialists from throughout the scientific community in Europe. Such a huge amount of data requires a vast range of scientific expertise that only international networking can provide. Taking into account the additional data products that are created from the basic observations leads to a total volume of about 1 Petabyte (1 million Gigabytes) for the complete dataset. Why was it necessary to create the Data Processing and Analysis Consortium? Who is taking part, who financed it, and how long is it expected to function?Ī primary motivation behind the Data Processing and Analysis Consortium (DPAC) is the unprecedented amount of data Gaia generates: surveying 1 billion stars, 70 times each over five years amounts to an average of 70 million objects observed each day! This translates into 40 Gigabytes of information per day, or 73 Terabytes over the full, nominal life of the mission. How long beyond the nominal mission could Gaia expect to function, assuming all key systems remain in working order?Īssuming nominal fuel consumption, the mission could be extended at least a full year and possibly up to late 2023. Consumables (mainly fuel) have been sized to extend the mission by at least 1 year. How long will the mission last, and could it be extended?Īfter 6 months’ commissioning, the nominal mission will last 5 years, ending in 2019. Gaia charts 10,000 times as many stars as Hipparcos, measuring their position and motion with 100 times greater precision. Hipparcos (1989-1993) catalogued more than 100,000 stars to a high precision and more than a million to lesser precision. How does Gaia’s performance compare with previous astrometry missions like Hipparcos? The interferometer concept was considered at the very inception of the mission but was quickly abandoned in favour of the current optical telescope design, which makes it possible to collect more signals and therefore to measure fainter stars. Initially Gaia was supposed to be an interferometry mission. Most member states also have a role in the science portion of the mission as part of the Data Processing and Analysis Consortium (DPAC) created to process and analyse scientific mission data. Companies from 15 member nations were awarded contracts to build the spacecraft. Which ESA Member States are participating in this mission and how?Īs an ESA Science Programme, contributions are mandatory, so all member states are taking part. Gaia was approved in 2000 as a European Space Agency Cornerstone Mission within ESA’s Horizon 2000 Plus science programme. In future, Gaia’s quasar measurements will redefine the fundamental reference frame used for all astronomical coordinate systems. Gaia also measures some 500,000 distant quasars, providing a connection to the reference frame currently defined in radio wavelengths. And by watching the large-scale motion of stars within the Galaxy, they probe the distribution of dark matter. Scientists also expect to discover thousands of exoplanets beyond the Solar System, tens of thousands of failed stars (brown dwarfs) and more than 20,000 exploding stars (supernovae). Gaia measures the position and velocity of more than one billion stars in the Milky Way – about 1% of the stars in the Galaxy – charts the three-dimensional distribution of these stars and determines their brightness, temperature, composition and motion through space. In so doing, it will also detect new asteroids and extragalactic sources such as quasars, find new exoplanets and even provide some tests of Einstein’s theory of general relativity.įrom the information obtained, astronomers will be able to understand much more about the structure, contents and evolution of our Galaxy, how it came into being and why it is the way it is. The Gaia mission will survey about one billion stars in the Milky Way Galaxy to create the largest and most accurate three-dimensional map of the Galaxy ever obtained.
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