Astronomers Confirm the First Image of a Planet Outside of Our Solar System.

(From AScribe)

LOS ANGELES -- An international team of astronomers reports April 29 the confirmation of the discovery of a giant planet, approximately five times the mass of Jupiter, that is gravitationally bound to a young brown dwarf. This discovery puts an end to a yearlong discussion on the nature of this object, which started with the detection of a red object close to the brown dwarf.

In February and March of this year, the astronomers took new images of the young brown dwarf and its giant planet companion with the state-of-the-science NACO instrument on the European Southern Observatory's (ESO) Very Large Telescope in northern Chile. The planet is near the southern constellation of Hydra and approximately 200 light years from Earth.

"Our new images show convincingly that this really is a planet, the first planet that has ever been imaged outside of our solar system," said Gael Chauvin, astronomer at the ESO and leader of the team of astronomers who conducted the study.

"The two objects - the giant planet and the young brown dwarf - are moving together; we have observed them for a year, and the new images essentially confirm our 2004 finding," said Benjamin Zuckerman, UCLA professor of physics and astronomy, member of NASA's Astrobiology Institute, and a member of the team. "I'm more than 99 percent confident. This is also the first time that a planet outside of our solar system has been detected far from a star or brown dwarf - nearly twice as far as the distance between Neptune and the sun."

Anne-Marie Lagrange, another member of the team from the Grenoble Observatory in France, said, "Our discovery represents a first step towards one of the most important goals of modern astrophysics: to characterize the physical structure and chemical composition of giant and, eventually, terrestrial-like planets."

Last September, the same team of astronomers reported a faint reddish speck of light in the close vicinity of a young brown dwarf. The feeble object, now called 2M1207b, is more than 100 times fainter than the brown dwarf, 2M1207A. The spectrum of 2M1207b presents a strong signature of water molecules, thereby confirming that it must be cold. Based on the infrared colors and the spectral data, evolutionary model calculations led to the conclusion that 2M1207b is a five-Jupiter-mass planet. Its mass can be estimated also by use of a different method of analysis, which focuses on the strength of its gravitational field; this technique suggests that the mass might be even less than that of five Jupiters.