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COROT-7b (previously named COROT-Exo-7b) is an exoplanet orbiting around the star COROT-7, in the constellation Monoceros, at 489 light years from Earth. The discovery of COROT-7b, the first rocky planet, was announced on 3 February 2009, during the COROT Symposium 2009 in Paris. 
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Title: Spitzer Infrared Observations and Independent Validation of the Transiting Super-Earth CoRoT-7b
Authors: Francois Fressin, Guillermo Torres, Frederic Pont, Heather A. Knutson, David Charbonneau, Tsevi Mazeh, Suzanne Aigrain, Malcolm Fridlund, Christopher E. Henze, Tristan Guillot, Heike Rauer

The detection and characterization of the first transiting super-Earth, CoRoT-7 b, has required an unprecedented effort in terms of telescope time and analysis. Although the star does display a radial velocity signal at the period of the planet, this has been difficult to disentangle from the intrinsic stellar variability, and pinning down the velocity amplitude has been very challenging. As a result, the precise value of the mass of the planet - and even the extent to which it can be considered to be confirmed - have been debated in the recent literature, with six mass measurements published so far based on the same spectroscopic observations, ranging from about 2 to 8 Earth masses. Here we report on an independent validation of the planet discovery, using one of the fundamental properties of a transit signal: its achromaticity. We observed four transits of CoRoT-7 b with Spitzer, in order to determine whether the depth of the transit signal in the near-infrared is consistent with that observed in the CoRoT bandpass, as expected for a planet. We detected the transit and found an average depth of 0.426 ±0.115 mmag at 4.5 {\mu}m, which is in good agreement with the depth of 0.350 ±0.011 mmag found by CoRoT. These observations place important constraints on the kinds of astrophysical false positives that could mimic the signal. Combining this with additional constraints reported earlier, we performed an exhaustive exploration of possible blends scenarios for CoRoT-7 b using the BLENDER technique. We are able to rule out the vast majority of false positives, and the remaining ones are found to be much less likely than a true transiting planet. We thus validate CoRoT-7 b as a bona-fide planet with a very high degree of confidence, independently of any radial-velocity information. Our Spitzer observations have additionally allowed us to significantly improve the ephemeris of the planet.

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Title: On the Mass of CoRoT-7b
Authors: Artie P. Hatzes, Malcolm Fridlund, Gil Nachmani, Tsevi Mazeh, Diana Valencia, Guillaume Hebrard, Ludmila Carone, Martin Paetzold, Stephane Udry, Francois Bouchy, Pascal Borde, Hans Deeg, Brandon Tingley, Rudolf Dvorak, Davide Gandolfi, Sylvio Ferraz-Mello, Guenther Wuchterl, Eike Guenther, Heike Rauer, Anders Erikson, Juan Cabrera, Szilard Csizmadia, Alain Leger, Helmut Lammer, Joerg Weingrill, Didier Queloz, Roi Alonso, Jean Schneider

The mass of CoRoT-7b, the first transiting superearth exoplanet, is still a subject of debate. A wide range of masses have been reported in the literature ranging from as high as 8 Earth masses to as low as 2.3 Earth masses. Although most mass determinations give a density consistent with a rocky planet, the lower value permits a bulk composition that can be up to 50% water. We present an analysis of the CoRoT-7b radial velocity measurements that uses very few and simple assumptions in treating the activity signal. By only analysing those radial velocity data for which multiple measurements were made in a given night we remove the activity related radial velocity contribution without any a priori model. We demonstrate that the contribution of activity to the final radial velocity curve is negligible and that the K-amplitude due to the planet is well constrained. This yields a mass of 7.42 ±1.21 Earth masses and a mean density of rho = 10.4 ±1.8 gm cm^-3. CoRoT-7b is similar in mass and radius to the second rocky planet to be discovered, Kepler-10b, and within the errors they have identical bulk densities - they are virtual twins. These bulk densities lie close to the density - radius relationship for terrestrial planets similar to what is seen for Mercury. CoRoT-7b and Kepler-10b may have an internal structure more like Mercury than the Earth.

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Title: The extreme physical properties of the CoRoT-7b super-Earth
Authors: A. Léger, O. Grasset, B. Fegley, F. Codron, A. F. Albarede, P. Barge, R. Barnes, P. Cance, S. Carpy, F. Catalano, C. Cavarroc, O. Demangeon, S. Ferraz-Mello, P. Gabor, J.-M. Griessmeier, J. Leibacher, G. Libourel, A-S. Maurin, S.N. Raymond, D. Rouan, B. Samuel, L. Schaefer, J. Schneider, P. A. Schuller, F. Selsis, C. Sotin

The search for rocky exoplanets plays an important role in our quest for extra-terrestrial life. Here, we discuss the extreme physical properties possible for the first characterized rocky super-Earth, CoRoT-7b (R_pl = 1.58 ± 0.10 R_Earth, Mpl = 6.9 ± 1.2 M_Earth). It is extremely close to its star (a = 0.0171 AU = 4.48 R_st), with its spin and orbital rotation likely synchronised. The comparison of its location in the (Mpl, Rpl) plane with the predictions of planetary models for different compositions points to an Earth-like composition, even if the error bars of the measured quantities and the partial degeneracy of the models prevent a definitive conclusion. The proximity to its star provides an additional constraint on the model. It implies a high extreme-UV flux and particle wind, and the corresponding efficient erosion of the planetary atmosphere especially for volatile species including water. Consequently, we make the working hypothesis that the planet is rocky with no volatiles in its atmosphere, and derive the physical properties that result. As a consequence, the atmosphere is made of rocky vapours with a very low pressure (P \leq 1.5 Pa), no cloud can be sustained, and no thermalisation of the planetary is expected. The dayside is very hot (2474 \leq 71 K at the sub-stellar point) while the nightside is very cold (50 to 75 K). The sub-stellar point is as hot as the tungsten filament of an incandescent bulb, resulting in the melting and distillation of silicate rocks and the formation of a lava ocean. These possible features of CoRoT-7b could be common to many small and hot planets, including the recently discovered Kepler-10b. They define a new class of objects that we propose to name "Lava-ocean planets".

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Oceans of lava might bubble on its surface. Hot pebbles may rain down from the sky. But the extrasolar planet CoRoT-7b is considered to be the most Earthlike world yet found outside our solar system.
A recent study, however, suggests that Earth might not be the best basis for comparison. Instead, the authors argue, CoRoT-7b is the first in a new class of exoplanets: a super-Io.

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The planet, tagged CoRoT-7b, first hit the headlines last September when a team of astronomers confirmed the orb as the smallest exoplanet yet found. Its diameter is roughly 1.7 times that of Earth. Based on its size and mass, its density is similar to Earth's, indicating that it is a rocky Earth-like orb.
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Most Earthlike Exoplanet Started out as Gas Giant

The most earthlike planet yet found around another star may be the rocky remains of a Saturn-sized gas giant, according to research presented today at the American Astronomical Society meeting in Washington.

"The first planets detected outside our solar system 15 years ago turned out to be enormous gas-giants in very tight orbits around their stars. We call them 'hot Jupiters,' and they weren't what astronomers expected to find. Now, we're beginning to see Earth-sized objects in similar orbits. Could there be a connection?" - Brian Jackson at NASA's Goddard Space Flight Centre in Greenbelt, Md.

Jackson and his colleagues turned to CoRoT-7b, the smallest planet and the most like Earth that astronomers have found to date. Discovered in February 2009 by the Convection, Rotation and Planetary Transits (CoRoT) satellite, a mission led by the French Space Agency, CoRoT-7b takes just 20.4 hours to circle its sunlike star, located 480 light-years away in the constellation Monoceros. Astronomers believe the star is about 1.5 billion years old, or about one-third the sun's age.

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First Earth-like planet spotted outside solar system likely a volcanic wasteland

When scientists confirmed in October that they had detected the first rocky planet outside our solar system, it advanced the longtime quest to find an Earth-like planet hospitable to life. The rocky planet CoRoT-7 b is, however, a forbidding place. If its orbit is not almost perfectly circular, then the planet might be undergoing continuous, fierce volcanic eruptions, according to information presented at the American Astronomical Society meeting.
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Title: The CoRoT-7 planetary system: two orbiting super-Earths
Authors: D. Queloz, F. Bouchy, C. Moutou, A. Hatzes, G. Hébrard, R. Alonso, M. Auvergne, A. Baglin, M. Barbieri, P. Barge, W. Benz, P. Bordé, H. J. Deeg, M. Deleuil, R. Dvorak, A. Erikson, S. Ferraz Mello, M. Fridlund, D. Gandolfi, M. Gillon, E. Guenther, T. Guillot, L. Jorda, M. Hartmann, H. Lammer, A. Léger, A. Llebaria, C. Lovis, P. Magain, M. Mayor, T. Mazeh, M. Ollivier, M. Pätzold, F. Pepe, H. Rauer, D. Rouan, J. Schneider, D. Segransan, S. Udry and G. Wuchterl

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Simulation suggests rocky exoplanet has bizarre atmosphere
According to models by scientists at Washington University in St. Louis, COROT-7b's atmosphere is made up of the ingredients of rocks and when "a front moves in," pebbles condense out of the air and rain into lakes of molten lava below.

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