* Astronomy

Members Login
Username 
 
Password 
    Remember Me  
Post Info TOPIC: Kepler-10b


L

Posts: 131433
Date:
RE: Kepler-10b
Permalink  
 


Title: Atmospheric mass loss and evolution of short-period exoplanets: the examples of CoRoT-7b and Kepler-10b
Authors: Hiroyuki Kurokawa (1 and 2), Lisa Kaltenegger (2 and 3) ((1) Tokyo Institute of Technology, (2) Max Planck Institut fuer Astronomie, (3) Harvard Smithsonian Center for Astrophysics)

Short-period exoplanets potentially lose envelope masses during their evolution because of atmospheric escape caused by the intense XUV radiation from their host stars. We develop a combined model of atmospheric mass loss calculation and thermal evolution calculation of a planet to simulate its evolution and explore the dependences on the formation history of the planet. Thermal atmospheric escape as well as the Roche-lobe overflow contributes to mass loss. The maximum initial planetary model mass depends primarily on the assumed evolution model of the stellar XUV luminosity. We adapt the model to CoRoT-7b and Kepler-10b to explore the evolution of both planets and the maximum initial mass of these planets. We take the recent X-ray observation of CoRoT-7 into account and exploring the effect of different XUV evolution models on the planetary initial mass. Our calculations indicate that both hot super Earths could be remnants of Jupiter mass gas planets.

Read more (969kb, PDF)



__________________


L

Posts: 131433
Date:
Kepler-10c
Permalink  
 


A new planetary member of the Kepler-10 solar system was announced today. Using data from NASA's Spitzer Space Telescope, members of the Kepler science team confirmed a new planet, dubbed Kepler-10c.
The Kepler-10 star system is located about 560 light-years away near the Cygnus and Lyra constellations. The Kepler telescope has discovered two planets around this star. Kepler-10b is, to date, the smallest known rocky exoplanet, or planet outside our solar system (dark spot against yellow sun). This planet, which has a radius of 1.4 times that of Earth's, whips around its star every 0.8 days. Its discovery was announced in Jan. 2011.

Read more 



__________________


L

Posts: 131433
Date:
RE: Kepler-10b
Permalink  
 


'The Rocky Planet, Kepler 10B' - Geoff Marcy 



__________________


L

Posts: 131433
Date:
Permalink  
 

Title: The orbital phases and secondary transit of Kepler-10b - A physical interpretation based on the Lava-ocean planet model
Authors: Daniel Rouan, Hans J. Deeg, Olivier Demangeon, Benjamin Samuel, Céline Cavarroc, Bruce Fegley, Alain Léger

The Kepler mission has made an important observation, the first detection of photons from a terrestrial planet by observing its phase curve (Kepler-10b). This opens a new field in exoplanet science: the possibility to get information about the atmosphere and surface of rocky planets, objects of prime interest. In this letter, we apply the Lava-ocean model to interpret the observed phase curve. The model, a planet with no atmosphere and a surface partially made of molten rocks, has been proposed for planets of the class of CoRoT-7b, i.e. rocky planets very close to their star (at few stellar radii). Kepler-10b is a typical member of this family. It predicts that the light from the planet has an important emission component in addition to the reflected one, even in the Kepler spectral band. Assuming an isotropical reflection of light by the planetary surface (Lambertian-like approximation), we find that a Bond albedo of \sim50% can account for the observed amplitude of the phase curve, as opposed to a first attempt where an unusually high value was found. We propose a physical process to explain this still large value of the albedo. The overall interpretation can be tested in the future with instruments as JWST or EChO. Our model predicts a spectral dependence that is clearly distinguishable from that of purely reflected light, and from that of a planet at a uniform temperature.

Read more  (1509kb, PDF)



__________________


L

Posts: 131433
Date:
Kepler-10c
Permalink  
 


Title: Kepler-10c, a 2.2-Earth radius transiting planet in a multiple system
Authors: Francois Fressin, Guillermo Torres, Jean-Michel Desert, David Charbonneau, Natalie M. Batalha, Jonathan J. Fortney, Jason F. Rowe, Christopher Allen, William J. Borucki, Timothy M. Brown, Stephen T. Bryson, David R. Ciardi, William D. Cochran, Drake Deming, Edward W. Dunham, Daniel C. Fabrycky, Thomas N. Gautier III, Ronald L. Gilliland, Christopher E. Henze, Matthew J. Holman, Steve B. Howell, Jon M. Jenkins, Karen Kinemuchi, Heather Knutson, David G. Koch, David W. Latham, Jack J. Lissauer, Geoffrey W. Marcy, Darin Ragozzine, Dimitar D. Sasselov, Martin Still, Peter Tenenbaum, Kamal Uddin

The Kepler Mission has recently announced the discovery of Kepler-10 b, the smallest exoplanet discovered to date and the first rocky planet found by the spacecraft. A second, 45-day period transit-like signal present in the photometry from the first eight months of data could not be confirmed as being caused by a planet at the time of that announcement. Here we apply the light-curve modelling technique known as BLENDER to explore the possibility that the signal might be due to an astrophysical false positive (blend). To aid in this analysis we report the observation of two transits with the Spitzer Space Telescope at 4.5 {\mu}m. When combined they yield a transit depth of 344 ±85 ppm that is consistent with the depth in the Kepler passband (376 ±9 ppm, ignoring limb darkening), which rules out blends with an eclipsing binary of a significantly different colour than the target. Using these observations along with other constraints from high resolution imaging and spectroscopy we are able to exclude the vast majority of possible false positives. We assess the likelihood of the remaining blends, and arrive conservatively at a false alarm rate of 1.6 x 10-5 that is small enough to validate the candidate as a planet (designated Kepler-10 c) with a very high level of confidence. The radius of this object is measured to be Rp = 2.227+0.052 -0.057 Earth radii. Kepler-10 c represents another example (with Kepler-9 d and Kepler-11 g) of statistical "validation" of a transiting exoplanet, as opposed to the usual "confirmation" that can take place when the Doppler signal is detected or transit timing variations are measured. It is anticipated that many of Kepler's smaller candidates will receive a similar treatment since dynamical confirmation may be difficult or impractical with the sensitivity of current instrumentation.

Read more  (1102kb, PDF)



__________________


L

Posts: 131433
Date:
Permalink  
 

A new planetary member of the Kepler-10 solar system was announced today. Using data from NASA's Spitzer Space Telescope, members of the Kepler science team confirmed a new planet, dubbed Kepler-10c.
The Kepler-10 star system is located about 560 light-years away near the Cygnus and Lyra constellations. The Kepler telescope has discovered two planets around this star. Kepler-10b is, to date, the smallest known rocky exoplanet, or planet outside our solar system (dark spot against yellow sun). This planet, which has a radius of 1.4 times that of Earth's, whips around its star every .8 days. Its discovery was announced in Jan. 2011.
Now, in May 2011, the Kepler team is announcing another member of the Kepler-10 family, called Kepler-10c. It's bigger than Kepler-10b with a radius of 2.2 times that of Earth's, and it orbits the star every 45 days. Both planets would be blistering hot worlds.

Read more 



__________________


L

Posts: 131433
Date:
Kepler-10
Permalink  
 


It has found a Sun-like star 173 parsecs away - relatively close by galactic standards - harbouring a planet that is just 40% larger than Earth, although it is uninhabitably hot. Supporting measurements of the planet's mass, gathered at the Keck Observatory on Mauna Kea, Hawaii, suggest that the planet's density is 1.6 times that of Earth, implying a rocky composition.
The new-found planet orbits its star - designated Kepler 10 - every 20 hours, at a distance of 2.5 million kilometres. This is less than 2% of the distance separating Earth and the Sun, ensuring that the planet is more 'terra lava' than terra firma, with a surface temperature of 1,800 °C, hot enough to melt silicate rock.

Read more

__________________


L

Posts: 131433
Date:
RE: Kepler-10b
Permalink  
 


NASA's Kepler mission confirmed the discovery of its first rocky planet, named Kepler-10b. Measuring 1.4 times the size of Earth, it is the smallest planet ever discovered outside our solar system.
The discovery of this so-called exoplanet is based on more than eight months of data collected by the spacecraft from May 2009 to early January 2010.
Kepler's ultra-precise photometer measures the tiny decrease in a star's brightness that occurs when a planet crosses in front of it. The size of the planet can be derived from these periodic dips in brightness. The distance between the planet and the star is calculated by measuring the time between successive dips as the planet orbits the star.
Kepler is the first NASA mission capable of finding Earth-size planets in or near the habitable zone, the region in a planetary system where liquid water can exist on the planet's surface. However, since it orbits once every 0.84 days, Kepler-10b is more than 20 times closer to its star than Mercury is to our sun and not in the habitable zone.
Kepler-10 was the first star identified that could potentially harbour a small transiting planet, placing it at the top of the list for ground-based observations with the W.M. Keck Observatory 10-meter telescope in Hawaii.
Scientists waiting for a signal to confirm Kepler-10b as a planet were not disappointed. Keck was able to measure tiny changes in the star's spectrum, called Doppler shifts, caused by the telltale tug exerted by the orbiting planet on the star.



__________________


L

Posts: 131433
Date:
Permalink  
 

Kepler-10b orbits a 12 billion year old star similar in size and temperature to our Sun.

Kepler 10b is 1.4 times Earth's size, but 4.6 times heavier than Earth. The new exoplanet has an orbital period of only 0.84 days. It may well have a rocky surface like Earth but it is very close to the star, so it is extremely hot - about 1560 degrees Celsius on the surface, so there is no possibility for life as we know it on Earth
Read more (Danish)


__________________


L

Posts: 131433
Date:
Permalink  
 

NASA Ames scientists discover Earth-sized planet

The place is inhospitable, with molten temperatures and possibly clouds of melted silicon. But a discovery across the galaxy is giving hope to searchers of intelligent life.
A team led by NASA Ames researchers has confirmed the existence of the first rocky planet outside our solar system. Kepler-10b is closest in size to Earth of 519 extra-solar planets discovered so far. It is about 1½ times the Earth's diameter and speeding around a star similar to our sun in the constellation Cygnus, about 560 light-years away



A new planet discovery will be announced Monday Jan. 10 during the 'Exoplanets & Their Host Stars' presentation at the American Astronomical Society (AAS) conference in Seattle, Washington.


__________________
Page 1 of 1  sorted by
 
Quick Reply

Please log in to post quick replies.



Create your own FREE Forum
Report Abuse
Powered by ActiveBoard