Topic: extrasolar planet news

[Astronuc]

Catalog of Nearby Exoplanets
Authors: R. P. Butler, J. T. Wright, G. W. Marcy, D. A Fischer, S. S. Vogt, C. G. Tinney, H. R. A. Jones, B. D. Carter, J. A. Johnson, C. McCarthy, A. J. Penny
(Submitted on 21 Jul 2006)
http://arxiv.org/abs/astro-ph/0607493
and
http://www.universe.nasa.gov/exoplanets_stars/
NASA's Spitzer First to Crack Open Light of Faraway Worlds
http://www.nasa.gov/mission_pages/spitzer/news/spitzer-20070221-full.html

Navigator Program Science Overview
Submitted to the NASA-NSF ExoPlanet Task Force, 2 April 2007
http://exoplanets.jpl.nasa.gov/documents/NP_sci_overview_070402_final-traub.pdf

[Astronuc]

Terrestrial Planets Might Form Around Many, Maybe Most, Nearby Sun-like Stars

ScienceDaily (Feb. 18, 2008) ? Astronomers have discovered that terrestrial planets might form around many, if not most, of the nearby sun-like stars in the disk of our galaxy. These new results suggest that worlds with potential for life might be more common than thought.

University of Arizona astronomer Michael Meyer led a Legacy Science Program with NASA's Spitzer Space Telescope to determine whether planetary systems like ours are common or rare in the Milky Way galaxy. Meyer and his colleagues found that at least 20 percent, and possibly as many as 60 percent, of stars similar to the sun are candidates for forming rocky planets.

The astronomers surveyed six groups of stars with masses comparable to our sun using Spitzer, which includes an instrument built at UA's Steward Observatory by a team led by Professor George Rieke. The stars were grouped by age, ranging from three-to-10 million years, 10-to-30 million years, 30-to-100 million years, 100-to-300 million years, 300 million to one billion years and one-to-three billion years old.

http://www.sciencedaily.com/releases/2008/02/080217102133.htm
 
 

[Astronuc]

Fomalhaut b and the planets of HR 8799, whose discovery was announced simultaneously, were the first confirmed extrasolar planets discovered via direct imaging.  The planet, which is 25 ly from earth in the direction of the constellation Piscis Austrinus, was discovered orbiting the A-type main sequence star Fomalhaut in 2008 in photos taken by the Hubble Space Telescope.
 
http://en.wikipedia.org/wiki/Fomalhaut_b
 
Refer to -
Kalas, Paul; Graham, James R.; Clampin, Mark (2005). "A planetary system as the origin of structure in Fomalhaut's dust belt". Nature 435 (7045): 1067?1070.
http://arxiv.org/abs/astro-ph/0506574

[Astronuc]

Scientists discover a nearly Earth-sized planet
http://news.yahoo.com/s/ap/20090422/ap_on_sc/eu_britain_new_planet
 

HATFIELD, England ? In the search for Earth-like planets, astronomers zeroed in on two places that look awfully familiar to home. One is close to the right size. The other is in the right place. European researchers said they not only found the smallest exoplanet ever, called Gliese 581 e, but realized that a neighboring planet discovered earlier, Gliese 581 d, was in the prime habitable zone for potential life.
 
"The Holy Grail of current exoplanet research is the detection of a rocky, Earth-like planet in the 'habitable zone,'" said Michel Mayor, an astrophysicist at Geneva University in Switzerland.
 
An American expert called the discovery of the tiny planet "extraordinary."
 
Gliese 581 e is only 1.9 times the size of Earth ? while previous planets found outside our solar system are closer to the size of massive Jupiter, which NASA says could swallow more than 1,000 Earths.
 
Gliese 581 e sits close to the nearest star, making it too hot to support life. Still, Mayor said its discovery in a solar system 20 1/2 light years away from Earth is a "good example that we are progressing in the detection of Earth-like planets."
 . . . .
Gliese 581 d is probably too large to be made only of rocky material, fellow astronomer and team member Stephane Udry said, adding it was possible the planet had a "large and deep" ocean.
. . . .

[Astronuc]

NASA's Kepler Mission Discovers Two Planets Transiting the Same Star

Ref: http://en.wikipedia.org/wiki/Kepler-9

"The observations show Kepler-9b is the larger of the two planets, and both have masses similar to but less than Saturn. Kepler-9b lies closest to the star with an orbit of about 19 days, while Kepler-9c has an orbit of about 38 days."

Ref: http://www.nasa.gov/centers/ames/new...0/10-73AR.html

Based on the masses 0.252 MJ and 0.151 MJ cited by Wikipedia, those are roughly 80 M_earth and 48 M_earth, respectively. Jupiter is about 318 M_earth.

[Astronuc]

Another exciting discovery - only 127 ly from earth

Richest Planetary System Discovered
Up to seven planets orbiting a Sun-like star
http://www.eso.org/public/news/eso1035/

Astronomers using ESO's world-leading HARPS instrument have discovered a planetary system containing at least five planets, orbiting the Sun-like star HD 10180. The researchers also have tantalising evidence that two other planets may be present, one of which would have the lowest mass ever found. This would make the system similar to our Solar System in terms of the number of planets (seven as compared to the Solar System's eight planets). Furthermore, the team also found evidence that the distances of the planets from their star follow a regular pattern, as also seen in our Solar System.

''We have found what is most likely the system with the most planets yet discovered,'' says Christophe Lovis, lead author of the paper reporting the result. ''This remarkable discovery also highlights the fact that we are now entering a new era in exoplanet research: the study of complex planetary systems and not just of individual planets. Studies of planetary motions in the new system reveal complex gravitational interactions between the planets and give us insights into the long-term evolution of the system''

The team of astronomers used the HARPS spectrograph, attached to ESO's 3.6-metre telescope at La Silla, Chile, for a six-year-long study of the Sun-like star HD 10180, located 127 light-years away in the southern constellation of Hydrus (the Male Water Snake). HARPS is an instrument with unrivalled measurement stability and great precision and is the world's most successful exoplanet hunter.

. . . .

 

[Astronuc]

NASA finds new planet Kepler 22b outside solar system with temperature right for life

http://www.washingtonpost.com/national/nasa-finds-new-planet-kepler-22b-outside-solar-system-with-temperature-right-for-life/2011/12/07/gIQAPfzFdO_story.html

The surface temperature may be close to that of earth. The annual period is about 290 days.

Kepler 22b is about 2.4 times the size of earth, so gravity is stronger.

It's about 600 ly distant from earth.


Interestingly, the article reports that "so far the Kepler telescope has spotted 2,326 candidate planets outside our solar system with 139 of them potentially habitable ones."