Space telescopes

The first space telescope to track the exoplanets is French.
The industrial contract was signed June 19, 2003 between CNES and Alcatel. Corot is responsible for detecting extrasolar planets in other solar systems and explore the mysteries concealed in the heart of stars. The mission conducted under the auspices of the Center National d'Etudes Spatiales (CNES) is conducted in cooperation with international participation of the European Space Agency (ESA) and various countries mostly European.
Convection and rotation refers to the ability of satellite to probe the interior of stars to study the acoustic waves that ripple across the surface, a technique called stellar seismology" asteroseismology.
Transit global refers to the technique used to detect the presence of a planet orbiting a star with the decrease in brightness caused it past the star.
To fill its two scientific objectives, COROT will monitor some 120 000 stars with his telescope of 30 cm in diameter.
The satellite is located at 900 km altitude in a circular orbit with an inclination of 90 °. This altitude can be repeated every seven days the cycle of operations. This orbit was chosen because it allows continuous observation for more than 150 days, the center of the galaxy, and was in the opposite direction in winter.

It is unlikely that the Space Telescope uncovers planets the size of Earth.
During the 10 years that followed the discovery in 1995 of the first exoplanet, 51 Pegasi b, 220 planets have been detected by large ground-based observatories. The satellite COROT promises to find many more during its two-year mission and a half and push the limits of our knowledge allowing us to discover planets of smaller and smaller.
When train its instruments on a star, COROT will also observe "stellar earthquakes, these acoustic waves generated deep inside a star that send ripples across its surface, altering its brightness.
The nature of the ripples allows astronomers to calculate the precise mass, age and chemical composition of stars.
CoRoT has garnered a rich harvest in 2006 and unearthed in 2009, the smallest exoplanets. Unfortunately, this planet orbits very close to its star and hence its surface temperature reached 1 500 ° C.

Nota: This is a 2.1B Soyuz rocket, which took off at 15h23 (Paris time) December 27, 2006 from its launch pad of the Baikonur Cosmodrome to file COROT in orbit.

* Image of artist's Corot space telescope

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

Hubble

The spatial telescope Hubble (Hubble Space Telescope or HST) is a telescope in orbit in approximately 560 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 Space Telescope Hubble around the Earth.
© ESA & Hubble European Space Agency Information Centre (M. Kornmesser & L. L. Christensen)

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

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.
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.

* Image of artist of the space telescope Newton

Herschel

The Herschel satellite is equipped with a telescope of 3.5 meters in diameter and weighs 3 300 kg for a size of 9m x 4m x 4m.
He will observe the universe in the infrared and submillimeter distance in wavelengths of 60 microns to 670 microns, a window of the electromagnetic spectrum poorly explored. It will in particular study the formation of galaxies and stars.
The detectors traditionally used for imaging in this wavelength range are bolometers. These detectors measure the intensity of infrared radiation through the rise in temperature absorbing material.
Service d'Astrophysique (SAp) at CEA-DAPNIA participates in the production of scientific instruments that are onboard the satellite Herschel Space Observatory of the future European Space Agency (ESA).
The launch by Ariane 5, planned for 2007 was held May 14, 2009 on the launch pad at Kourou in Guyana.

The Planck spacecraft was part of the trip. On July 3, 2009, Planck reached L2 Lagrange point and was placed on a course called Lissajous orbit.

nota : The Lagrangian points: the L2 point, the object orbits the Sun at the same angular velocity as the Earth. A satellite on one of these points do not move any more and turned together, permanently, with the Earth around the Sun. On this point is since June 2001, the WMAP (Wilkinson Microwave Anisotropy Probe) and in 2011 the James Webb Space Telescope will join them.

* Thirty minutes after its launch, the instrument Herschel split the last stage of its launch vehicle and headed to the Lagrangian point L2 of the Earth-Sun at 1.5 million kilometers from Earth. Credit: ESA / D. Ducros, 2009

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

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Astronomy - october 15th 2007