ELISA and “The Gravitational Universe”
After missions to the moons of Jupiter and the study of the Universe in X-rays, the European Space Agency has officially announced the last argument of the third largest mission in the program Horizon 2000; it will be devoted to the study of gravitational waves.
The European Space Agency drops the trio on the study of the Cosmos. Gravitational Universe, namely “The Universe Gravity” is the theme of the third mission of class L (Large) or large, made official on 28 November by the ESA Science Programme Committee. So after JUICE, dedicated to studying the icy moons of Jupiter and Athena + , the future orbiting X-ray observatory, Europe is preparing to open a new window on the universe, that of gravitational waves. A “tune in” on these elusive signals there will be a spatial interferometer, whose draft was baptized (ELISA evolved Laser Interferometer Space Antenna) and that, according to current plans, will be operational in 2034. A step further will be LISA Pathfinder mission, which will be launched in 2015 and test it on the field, or in space, the key technologies for the future development of an ELISA.
We contacted Monica Hits, professor at the University of Milan Bicocca, which is part of the scientific team of Elisa, to tell us about this ambitious mission and its scientific objectives.
First of all, Professor Hits , why is it so important to study gravitational waves, so much so that the Scientific Committee of the ESA to approve this subject in his third major mission in the Horizon 2000 plan, expected in about twenty years?
So far, the vision of the universe that we have received from the information had been carried by electromagnetic waves, from radio waves to gamma rays. But we know that gravity is the engine that drives all cosmic processes. Even gravity has its messengers, the “gravitational waves “, or disruption of the texture of space-time that travels at the speed of light, produced by cosmic sources where gravity is extreme. Then look at the Universe in gravitational waves is an extraordinary challenge to reveal another invisible “face”, so far. One of the advantages of the study of these signals is that gravitational waves are not absorbed in their journey through space and give us access to such phenomena which occurred when the universe and cosmic structures were to form, to push us to the distant past just 200 million years after the Big Bang. The signals that are revealed by the mission science developed under the theme “Gravitational Universe” are those of low frequency associated with the union of two black holes with masses of million times bigger that of the Sun. The analysis of the shape of these waves allow us to get super accurate measurements of the masses of black holes and the extent of their rotation, so they can be traced back to the structure of space – time in their vicinity and perform tests on General Relativity . But not only can the frequency of observation of the future space observatory be revealed, but a sort of background noise of cosmic gravitational waves that was produced during the Big Bang. Its discovery will allow understanding the origin of the Universe and perhaps arriving at a quantum theory of gravitation.
2015 will see the launch of space interferometer LISA Pathfinder, a decisive step for the development of the mission associated with the theme of “The Universe Gravity”, or ELISA, which should fly around 2034. Elisa is a spatial interferometer which will consist of three satellites placed at the vertices of a perfect equilateral triangle, each at a distance of one million miles of each other and all moving on heliocentric orbit.