Stop the pixel presses!
We've got a planetary problem.
"In a wild turn of cosmic events, a group of astronomers is trying to reclaim the role of having made the first photograph of a planet around another star.
"[On April 30], an ESO team announced new observations of 2M1207b that convincingly show, they say, that their target is indeed a planet. If so, it could be remembered as the first picture of an exoplanet, since the team had already released the initial image last fall.
However... "earlier [in April], Ralph Neuhaeuser of the Astrophysical Institute & University Observatory said his team had made the first confirmed picture of a planet around another star called GQ Lupi, some 400 light-years away. In this case, also first reported by SPACE.com, the object was observed to be clearly bound to the star.
"The planet is thought to be one to two times as massive as Jupiter, according to the scientists who imaged it. It orbits a star similar to a young version of our Sun.
"GQ Lupi has been observed by a team of European astronomers since 1999. They have made three images using the European Southern Observatory's Very Large Telescope in Chile. The Hubble Space Telescope and the Japanese Subaru Telescope each contributed an image, too.
"While observations suggest the planet orbiting GQ Lupi is about twice as massive as Jupiter, there is a slight chance it is 42 times the mass of Jupiter -- so heavy that it would be considered a brown dwarf. The outlying models, however, are very unlikely to apply to the system, some astronomers said.
"'Based on what we know, that image is an image of an object much like Jupiter at an extremely young age,' said Ben Oppenheimer of the American Museum of Natural History, who was not involved in either study...
"The whole issue [of who saw a planet first] is further clouded by the fact that 2M1207b orbits a brown dwarf rather than a regular star. Brown dwarfs stars do not have enough mass to trigger the thermonuclear fusion that powers a regular star. So a planetary-mass object around them exists in an unusual system that is unlikely to have any chance of harboring life as we know it. It also may have had a different formation history.
"'Given the rather unusual properties of the 2M1207 system, the giant planet most probably did not form like the planets in our solar system," Gael Chauvin [lead researcher of the "brown-dwarf orbiter" team] said. 'Instead it must have formed the same way our Sun formed, by a one-step gravitational collapse of a cloud of gas and dust.'
"Alan Boss, a planet formation theorist at the Carnegie Institution of Washington, said both findings represent 'great stuff,' but he's not ready to draw firm conclusions about who wins.
"'This object [2M1207b] should be termed a sub-brown-dwarf (star), in order to convey this suspicion about its formation mechanism,' Boss said in an e-mail interview. 'A number of sub-brown dwarfs have been observed as single objects in regions of recent star formation, but 2M1207 would seem to be the first one in orbit around a brown dwarf (star). All in all, it is an excellent discovery of a new class of object, but it is unclear if this object should be termed a planet.'
Now here's the capper:
"There is no agreement among astronomers on the definition of the term 'planet.' A spirited debate dates back five years in regard to attempts to define [what is and what is not a planet].
"'I consider it as a planet, regardless whether it formed differently than Jupiter -- and regardless [of the fact that] it's orbiting a failed star instead of solar-type star," says Christophe Dumas, a colleague of Chauvin. 'Actually, this discovery is even more interesting due to the fact that the brown dwarf and the giant planet are not forming a "traditional" system as we know it from looking at our own solar system. We did not expect to find a giant planet in orbit around a brown dwarf and it's there.'
"For now, the International Astronomical Union lists 2M1207b as a 'possible planetary-mass companion to a brown dwarf.' The IAU catalogues the GQ Lupi discovery as 'a possible planetary-mass companion to a young star.'
"[On April 30], an ESO team announced new observations of 2M1207b that convincingly show, they say, that their target is indeed a planet. If so, it could be remembered as the first picture of an exoplanet, since the team had already released the initial image last fall.
However... "earlier [in April], Ralph Neuhaeuser of the Astrophysical Institute & University Observatory said his team had made the first confirmed picture of a planet around another star called GQ Lupi, some 400 light-years away. In this case, also first reported by SPACE.com, the object was observed to be clearly bound to the star.
"The planet is thought to be one to two times as massive as Jupiter, according to the scientists who imaged it. It orbits a star similar to a young version of our Sun.
"GQ Lupi has been observed by a team of European astronomers since 1999. They have made three images using the European Southern Observatory's Very Large Telescope in Chile. The Hubble Space Telescope and the Japanese Subaru Telescope each contributed an image, too.
"While observations suggest the planet orbiting GQ Lupi is about twice as massive as Jupiter, there is a slight chance it is 42 times the mass of Jupiter -- so heavy that it would be considered a brown dwarf. The outlying models, however, are very unlikely to apply to the system, some astronomers said.
"'Based on what we know, that image is an image of an object much like Jupiter at an extremely young age,' said Ben Oppenheimer of the American Museum of Natural History, who was not involved in either study...
"The whole issue [of who saw a planet first] is further clouded by the fact that 2M1207b orbits a brown dwarf rather than a regular star. Brown dwarfs stars do not have enough mass to trigger the thermonuclear fusion that powers a regular star. So a planetary-mass object around them exists in an unusual system that is unlikely to have any chance of harboring life as we know it. It also may have had a different formation history.
"'Given the rather unusual properties of the 2M1207 system, the giant planet most probably did not form like the planets in our solar system," Gael Chauvin [lead researcher of the "brown-dwarf orbiter" team] said. 'Instead it must have formed the same way our Sun formed, by a one-step gravitational collapse of a cloud of gas and dust.'
"Alan Boss, a planet formation theorist at the Carnegie Institution of Washington, said both findings represent 'great stuff,' but he's not ready to draw firm conclusions about who wins.
"'This object [2M1207b] should be termed a sub-brown-dwarf (star), in order to convey this suspicion about its formation mechanism,' Boss said in an e-mail interview. 'A number of sub-brown dwarfs have been observed as single objects in regions of recent star formation, but 2M1207 would seem to be the first one in orbit around a brown dwarf (star). All in all, it is an excellent discovery of a new class of object, but it is unclear if this object should be termed a planet.'
Now here's the capper:
"There is no agreement among astronomers on the definition of the term 'planet.' A spirited debate dates back five years in regard to attempts to define [what is and what is not a planet].
"'I consider it as a planet, regardless whether it formed differently than Jupiter -- and regardless [of the fact that] it's orbiting a failed star instead of solar-type star," says Christophe Dumas, a colleague of Chauvin. 'Actually, this discovery is even more interesting due to the fact that the brown dwarf and the giant planet are not forming a "traditional" system as we know it from looking at our own solar system. We did not expect to find a giant planet in orbit around a brown dwarf and it's there.'
"For now, the International Astronomical Union lists 2M1207b as a 'possible planetary-mass companion to a brown dwarf.' The IAU catalogues the GQ Lupi discovery as 'a possible planetary-mass companion to a young star.'
Stop the pixel presses!
We've got a planetary problem.
mr damon, 05:10
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