The first spatial telescope to pursue exoplanets is French. The industrial contract was signed on June 19th, 2003, between Cnes and Alcatel.
Corot COROT is the abbreviation of "COnvection, ROtation and global Transits", what corresponds to the scientific objectives of the mission. COROT is in charge of detecting exoplanets in the other solar systems and of studying the mysteries which conceals the heart of stars. This mission led under the aegis of the national centre for space research (CNES) is led in international cooperation with the cooperation of the European Space agency (ESA) and of the diverse for the greater part European countries. " Convection and rotation " make reference to the capacity of the satellite sound the inside of stars to study the acoustic waves which propagate on their surface, a called technique stellar or "asterosismologie" seismology.

"Global Transit" evokes the technique used to detect the presence of a planet in orbit around a star thanks to the decrease of luminosity which it provokes in passing in front of the star. To fill its two scientific objectives, COROT will observe more than 120 000 stars by means of its telescope 30 cm in diameter.

Image of artist of the space telescope Corot © Mylène Simoès

The satellite is placed in 900 km in height on a circular orbit with a slope of 90 °. This height allows to repeat, every seven days the cycle of the operations. This orbit was chosen because she allows the continuous observation during more than 150 days of the center of the galaxy in summer and the direction set in winter. The first discoveries of exoplanets, are foreseen in best in spring, 2007 for "Jupiter warm" les "Jupiter warm" are exoplanets of Io type the mass of which is lower in 13 times that of Jupiter and very close of their star. And the end of 2007 for " Super-Earth " .Les " Super-are in hiding " are similar telluric planets in the Earth and equal size unless 2,5 ground beams. Beyond, it is not very probable that a telluric planet of this size forms. It is however not very probable that this spatial telescope chases away planets of the size of the Earth. During 10 years which followed the discovery in 1995 of the first exoplanet, 51 Pegasi b, 220 other planets were detected by the big ground look-out observatories.

The satellite COROT should discover many the others during its mission of two and a half years and push away the limits of our knowledge by allowing us to discover more and more small planets. When it will aim its instruments at a star, COROT can also observe " stellar earthquakes ", these acoustic waves resulting from depths of the star which propagate on the surface of this one, modifying the luminosity. The nature of these vibrations will allow the astronomers to deduct exactly the mass, the age and the chemical composition of stars.

Le lanceur, une fusée Soyouz 2.1B, a décollé à 15h23 (heure de Paris) le 27 décembre 2006 de son pas de tir du cosmodrome de Baïkonour.

Spitzer

The space Telescope Spitzer Lyman Spitzer, Jr. (In June 26th, 1914 - March 31st, 1997) was an American astrophysicist, an author about 200 scientific articles (according to ADS / CDS (Nasa)), among whom 155 in first author. According to his biography, he would be the first one to have expressed the idea to send an in orbit ground telescope. He participated actively in the realization of the project of the spatial telescope Hubble. He was a prize-winner of the Medal Franklin in 1980 for his research works on the mechanisms of formation of stars. His name was given to the spatial telescope Spitzer (SIRTF) when it was sent into orbit.  Spitzer is the biggest infrared telescope launched by the NASA. These wavelengths which can not be usefully observed since the ground, only an object outside of the atmosphere, cooled cryogenically can make useful observations. This satellite is similar to the spatial telescope ISO launched by the ESA in 1995 and the life expectancy of which was of 28 months. The launch of the telescope was made by a rocket Delta II, on August 25th, 2003 on the Cap Canaveral in Florida. Before his launch, he was named SIRTF for Space Infrared Telescope Facility but was reappointed Spitzer, of the name of an American scientist, Lyman Spitzer. He can observe and detect the infrared radiation emitted by objects in wavelengths between three and hundred sixty micrometers.

He can make approximately 100 000 observations during his life, the forecast of which is of 5 years. Its unique orbit will allow its to use the cold temperatures of the space for its cooling (besides that supplied by 400 liters of liquid helium) and its solar panels will bring its the energy and will protect it from solar emissions (radiation and particles). The new very sensitive instruments of the telescope will allow to drill the space which is darkened by clouds of gas, the interstellar clouds which block telescopes working in the visible domain. It already brings new data about the formation of planets as well as on cold objects such as the brown dwarfs, and the infrared galaxies, the seats of formation of very intense star.

Image of artist of the space telescope Spitzer © Mylène Simoès

Hubble

The spatial telescope Hubble (Hubble Space Telescope or HST) is a telescope in orbit in approximately 600 kilometers in height, it makes a complete tour of the Earth every 100 minutes. It is named in honor of the astronomer Edwin Hubble Edwin Powell Hubble (in 20/11/1889 - 28/09/1953) American astronomer who showed that the Universe is expanding. Hubble is is born to Marshfield in the Missouri. He studies the mathematics and the astronomy to the university of Chicago where he) obtains his diploma in 1910. Holder of a scholarship, he crosses then 3 years to the university of Oxford where he obtains Master of Arts there straight ahead. He quickly returns to the astronomy to the look-out observatory Yerkes, where he receives his Ph. D. in 1917. Drag, the founder and the director of the observatory of the Mountain Wilson, near Pasadena in California, proposes him researcher's post. He pursues his works till the end of his life there On 28/09/1953.. Its launch The telescope was launched on April 25th, 1990 by the mission STS-31 of the Space shuttle Discovery. This launch had already been delayed in 1986 because of the disaster of the space shuttle Challenger in January of this year. , made April 25th, 1990 by a Space shuttle, is the fruit of a common project between the NASA and the ESA. This telescope has an optical resolution better than 0,1 assist of bow. It is planned to replace it in 2013 by the James Webb Space Telescope (previously named spatial Telescope new generation, Next Generation Space Telescope or NGST). The telescope Hubble weighs approximately 11 tons, is 13,2 meters long, has a maximum diameter of 4,2 meters and cost 2 billion US dollars.

It is a telescope reflector in two mirrors; the main mirror is one diameter 2,4 meters. It is coupled with diverse spectrometers and three cameras: one in narrow field for the weakly brilliant objects, the other one in wide field for the global images and one for the infrared. It employs two solar panels to produce some electricity, which is mainly used by cameras and four big steering wheels used to direct and stabilize the telescope. The infrared camera and the spectrometer multi-objects must be also cooled in 180 °C. The first images supplied by the telescope were generally considered as very disappointing by the astronomers and all those concerned by the project. These images were vague and, in spite of the treatment of image, did not reach the foreseen resolution.

The spatial Telescope Hubble seen by the Space shuttle Discovery during the second mission of maintenance of the Telescope, STS-82

Pamela

PAMELA (Payload for Antimatter Exploration and Light-nuclei Astrophysics) is a observatory in orbit intended to determine the characteristics of the black matter. The researchers in search of antimatter in the universe appeal to detectors embarked aboard spatial machines, such as PAMELA or AMS (modulate for the ISS, the international space station). Pamela was launched on June 15th, 2006 by a Russian rocket aboard a satellite Resurs DK1.

It will be the most complex detector of particles never launched in the space because he can detect and measure with an exceptional precision the load, the mass and the specter of energy of the cosmic particles which will strike its detector. The objective is to study the cosmic particles, their specter, their origin, the presence of antiparticles, and the possible presence of black matter.

Image of artist of the space telescope Pamela © Mylène Simoès

XMM-Newton

The European spatial telescope of the European Space agency ( E.S.A). XMM-Newton was launched on December 10th, 1999. It is the biggest observatory with X-rays never built. After one year of activity, the biggest observatory with X-rays never built delivers an impressive variety of scientific results. XMM-Newton allowed to discover of new heap of galaxies to considerable distances, several billion light years. This project aims at determining the distribution of the heap of galaxies in the distant Universe and at confronting it with the predictions of the models of evolution of the Universe. The Universe does not appear as a distribution of matter distributed in a uniform way but more as a set of strands constituted by galaxies gathering in the knots of these strands to form heap of galaxies.

They can contain thousands of galaxies, and their mass can reach a million billion times ( 1014 ) the mass of the Sun. The study of the formation of these heap, an important detail of the puzzle of the structure of the Universe, is at the same moment the object of numerous programs of observations and numeric simulations. But track down in the visible distant domain of the heap to reconstitute the puzzle of their formation raise very severe problems of observations because of the extreme weakness of the light signal reaching us.

Image of artist of the space telescope Newton © Mylène Simoès

Another technique, the observation in the field of the X-rays, is possible. Indeed, a not unimportant fraction (approximately 20 %) of the mass of a heap is constituted by a diffuse warm gas, situated between the galaxies. This gas is warmed, considering the high gravitational potential, in temperatures which could reach to reach several tens of million degrees. A gas raised to such temperatures is a powerful source of radiation X.

The strategy adopted by the international team within the framework of the program baptized "Poll of the structure with large scales with XMM" thus consists first of all in detecting the emission X of this warm gas and to look for by imaging in the same region of the sky the optical counterparts. The distances of the galaxies constituting the heap are finally determined thanks to spectroscopic measures. The imaging is led indeed has by using the telescope of 3,6 m of the

observatory (CFHT) Canada-France-Hawaii whereas the spectroscopic measures are led to one of the huge telescopes of the European observatory of the VLT. The extraordinary sensibility of the satellite XMM-Newton bound to the power of the means of observation on the ground operating in the visible domain so allows a considerable headway in the understanding of the formation of the heap distant and of the structure of the Universe.

Herschel

The satellite Herschel is equipped with a telescope 3,5 meters in diameter. He will observe the Universe in domains infrared distant and sub millimeter (60 microns - 670 microns). He will notably allow to study the formation of the galaxies and the stars. Detectors traditionally used for the imaging in this range of wavelength are bolometers. These detectors measure the intensity of the infrared radiation thanks to the rise in temperature of an absorbing material.
The Service of Astrophysics (SAp) of the CEA-DAPNIA participates at present in the realization of the scientific instruments which will be embarked aboard the satellite Herschel, the future spatial observatory of the European Space agency (ESA), the launch foreseen for 2007.

A patent of the Laboratory of Electronics of Information technology (LETI) and the Service of Astrophysics (SAp) of the CEA-DAPNIA concerning an original process for the detection of the radiation in infrared distant was put down in December, 2002 and has just been made public. It makes possible the detection of the infrared light for the biggest wavelengths (of 800 microns towards the mm) by detectors of type " bolometers " which measures the rise of temperature of a matter.

Image of artist of the space telescope Herschel © Mylène Simoès

MOST

The spatial telescope MOST (Microvariability and oscillation of STARS or Microvariability and Oscillation of Stars) is launched in the space in 2003. It is the first Canadian scientific satellite sent into orbit and completely conceived and built by Canada.
MOST is a small telescope dedicated only to the asterosismology, that is to the study of the vibrations which shake stars. The interest to study such vibrations is big because he allows to obtain information on the internal structure of a star, thus, on his dimensions, his mass and his constituents.
The project is introduced in 1996 by the researchers Slavek Rucinski of the Research center in Technologies of the Earth and the Space of Ontario, Jaymie Matthews and Tony Moffat.
Of the size and the shape of a big suitcase, the satellite weighs only 54 kilograms and is endowed with a telescope sophisticated extreme
 

reactionary of hardly 15 centimeters in diameter. Nevertheless, it is ten times as sensitive as the spatial telescope Hubble to detect the tiny variations of luminosity of stars due to the vibrations which shake their surface. MOST makes a complete orbit around the Earth every 101 minutes by way of both poles of the Earth. He can so cross 60 days to observe continuously the same star. Its life cycle should be from 5 to 10 years old. The first major discovery is made in 2004 concern Procyon, one of the stars the most studied by the astronomers. While we expect to see the celestial body vibrating, we notice that it is nothing. It contradicts 20 years of theories and observations so forcing the astrophysicists to rethink their models on stars. In 2005, MOST observes for the first time a huge planet which orbits if near its star host that this one sees itself forced to synchronize its rotation with the planet. Usually, it is the planets which synchronize their rotation with their star.

The spatial telescope MOST put in service in 2004.
Image of artist of the space telescope Most © Mylène Simoès

Soho

The mission SOHO has for objective to study the internal structure of the Sun, the heat of its atmosphere, the previous history of the Solar wind. The space probe SOHO is the fruit of a collaboration between the NASA and the ESA. It was launched on December 2nd, 1995 of the base of Cap Canaveral (USA) by a rocket Atlas II. In functioning since February, 1996, and in spite of a loss of contact of several months, the mission takes place outstandingly well and it is prolonged until 2007.
The distance Earth-sun is equal to 150 million kilometers. SOHO evolves on an orbit in halo around the point of Lagrange L1.

In this point, the strengths of gravitation exercised by the Sun and the Earth on an object balance each other, but the balance is unstable and SOHO thus describes an orbit around this particular point. The period of SOHO is equal to the period of revolution of the Earth around the Sun or approximately 365 Days.

Image of artist of the space telescope Soho © Mylène Simoès

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Astronomy - october 15th 2007