Interesting mission of Gaia
Gaia is a global space astrometry mission by European Space Agency (ESA). The root for the mission went to ESA’s Hipparcos mission (1989-1993) that gave the information of more than 100,000 stars to high precision.
Now, the mission is almost ready to be launched in November.
Structure:
Gaia has two optical telescopes working with three science instruments to study the location and velocities of stars and to split their light into a spectrum for detailed analysis.
Position:
Gaia will work from an orbit around the Sun at a distance of about 1.5 million km beyond the Earth’s orbit. This special location is known as L2 Lagrangian point.
Applications:
Gaia has been developed to get most precise three-dimensional (3D) map of our Galaxy by studying over a thousand million stars (10,00,00,00,00 stars).
“It will be a time-lapse movie and we’re going to watch it,” said Cambridge University’s Prof Gerry Gilmore.
“We will see the remnants, the debris streams, of the first shards that became what is today the Milky Way. We can run the process right back to the first things that ever happened. We will see the entire history of the Milky Way unfolding before our eyes.”
Gaia will work on each of the target star for about 72 times over a 5-year period. It will also study 500,000 distant quasars – remote astronomical objects releasing huge amounts of energy – and do several tests about Albert Einstein’s General Theory of Relativity.
Gaia has the ability to measure the positions of all objects even the objects about 400,000 times fainter than the objects that could be seen with the normal eye, i.e. objects of magnitude 20 (covering 330–1050 nm). Moreover, for objects brighter than magnitude 15, i.e. 4000 times fainter objects than the limit of normal eye, Gaia has the ability to measure the positions accurately to about 24 microarcseconds that can be compared to determining the diameter of human hair at a distance of about 1000 km.
Gaia mission has the ability to measure the distances of stars near the Galactic centre that is about 30,000 light-years away within an accuracy of 20%.
Structure of galaxy could help in Gaia mission as reported by researchers, “it is possible to push the limits of the Gaia space mission by analysing galaxy morphology.”
References:
Gaia – ESA
Gaia: The ‘impossible space mission’ ready to fly – BBC
A. Krone-Martins, C. Ducourant, R. Teixeira, L. Galluccio, P. Gavras, S. dos Anjos, R. E. de Souza, R. E. G. Machado, & J. -F. Le Campion (2013). Pushing the limits of the Gaia space mission by analyzing galaxy morphology Astronomy & Astrophysics arXiv: 1307.5732v1
