The European Space Agency selected, October 12, 6 space missions for the period 2008-2012: BepiColombo, GAIA, LISA, NGST, Solar Orbiter and Eddington ("in reserve").

 

Detailed information, in English, is available on the ESA site at this address or, in French at AFP

The Paris Observatory is implied in several of these missions, in particular in BepiColombo , GAIA , Solar Orbiter , Eddington .

Short description of these 4 missions:

BepiColombo

Mercury is certainly the telluric planet most badly known (telluric = having a solid surface like Mercury, Venus, Earth, Mars), while at the same time it poses several fundamental problems. Less than half of its surface was observed by the mission Mariner-10 in 1974, the only space exploration to date. One of the great surprises, at the time of the three meetings carried out in 1974, was the discovery of a magnetic field certainly weak (1/100 that of the Earth), but sufficient to create a significant obstacle to the solar wind flow and to form the strangest magnetosphere of the solar system.

How Mercury was formed? Why is it so dense? Is its core solidified? Where does its magnetic field come from? Which was its geological evolution? Which are the nature and the dynamics of its magnetosphere? Many questions defy a number of current models and require an intensive exploration.

The multidisciplinary and mainly interdisciplinary aspect appears very clearly in this mission; this is the main issue and extreme interest: for example the couplings between surface, exosphere (a variety of atmosphere in permanent reformation) and surrounding plasma must be understood perfectly, and this involves several scientific disciplines.

The precise knowledge of the orbital parameters of the Mercury orbitor will make it possible to carry out new tests of general relativity, and to measure with precision the quadrupolar moment of the sun as well as the temporal variation of the gravitational constant.

More informations here
and there

GAIA

The very precise determination of distances in the Universe is one of the major challenges of modern astronomy. GAIA will make it possible to reach an accuracy of 10 microseconds of degree on the trigonometrical parallaxes (the parallax is the reverse of the distance) for stars of apparent magnitude 15, that is to say the diameter of a hair seen from a distance of 1000 km. Distances of stars located far from the galactic center, up to the Large Magellanic Cloud for the brightest of them, will be determined with a precision better than ten percent.

These distances together with the systematic observation of the motions (tangent and radial), and of 15-color photometry for all objects up to apparent magnitude 20, will make it possible to irrigate many fields of astronomy and astrophysics:
- detailed analysis of the composition, formation and evolution of our Galaxy, characterization of the various stellar populations and identification of the vestiges of possible encounters with other galaxies
- detailed analysis of allphases of the stellar evolution
- calibration of the absolute luminosities of all distance indicators
- systematic detection, and characterization, of a few tens of thousands of large exo-planets, orbiting around all stars up to 200- 500 PC
- systematic observation of the small bodies of the solar system
- dynamical study of the galaxies of the Local Group, systematic observation of a few million galaxies and some 500 000 quasars
- new constraining tests of general relativity.

More informations here
and there

Solar Orbiter

Atmosphere of the sun and its environment - the heliosphere constitutes a unique field where can be directly observed and studied processes of fundamental physics common to the solar, stellar and astrophysical mediums, and with laboratory plasmas, under conditions impossible to reproduce in the terrestrial laboratories.

Using the techniques of propulsion and technology developed for BepiColombo, the mission Solar Orbiter will have an entirely new orbit, approaching the sun inside the Mercury orbit (up to 0,21 Astronomical Units of the sun), and getting out of the plane of the ecliptic, thus making it possible to explore unknown areas of the environment of our star.

In addition to a close and 'in situ' exploration of the sun and of its atmosphere, the mission Solar Orbiter has the originality to be able to follow the Co-rotation' sun ', a little like the geostationary satellites do it for the Earth, in order to observe continuously and closer the active areas of the sun: spots, etc, for a long period of time, much longer than what is possible from the Earth.

More informations here

Eddington

Eddington is a mission `in reserve' whose planning will be a function of the calendars of the NGST and LISA. The purpose of Eddington is:
- to probe the interior of stars through a kind of echography. One can deduce their evolution, their age to compare with the age of the Universe
- to detect a few hundreds of planets exterior to the solar system, of which a few tens similar to the Earth. The method used (`planetary transits') is the same one as that of the Corot satellite and makes it possible to measure the diameter of planets.

More informations here

Contacts: Jean-Louis Bougeret , for BepiColombo and for Solar Orbiter, Catherine Turon , for GAIA, Jean Schneider for Eddington.