(PLANETQUEST) -- The recently discovered two-tiered dust cloud orbiting the star 51 Ophiuchi is not just one of the most compact ever observed - it may be a snapshot of our own solar system's formative years.
"We don't know the exact age of this system," said astronomer Chris Stark, who led the research team,"but it could be an early analogue of how our own solar system used to be." Stark and his group made their observation using the Keck Interferometer Nuller, an instrument that cancels out the light of a star so its surrounding dust can be more clearly detected.
The dust cloud orbiting 51 Ophiuchi has two parts: a compact inner disk with large grains of dust and rock, and an extended outer disk made up of much finer material. "Several attempts have been made to image this disk before," Stark said, "but the brightest part of the disk is so compact that it takes an interferometer like the Keck Nuller to resolve it."
According to Marc Kuchner, a member of the research team, the inner disk resembles a "baby Asteroid Belt," full of the same material that formed the rocky inner planets of our own solar system, the leftovers of which now orbit in the Asteroid Belt between Mars and Jupiter. This planetary nursery "may be forming Earth-like planets right now," Kuchner says.
Kuchner notes that if the system has any Jupiter-like gas giant planets, they have likely already formed in the more diffuse outer disk. But that dust will make any planet observations difficult. "The dust is an obstacle, but it may be possible to see planets orbiting 51 Ophiuchi someday," Kuchner said.
The discovery is a boon for astronomers trying to understand our own planet's origin. "This data can help us learn how planets like Earth evolve, as well as the origin of our asteroid belt," Kuchner says.
Dust busting
51 Ophiuchi is the first published discovery in a survey of dust discs being performed by the Keck Interferometer Nuller. "The nuller was envisioned to do this survey," Kuchner said. "By taking light from the two Keck telescopes and combining them, we can cancel out the light of a star and get a better look at its exozodiacal disk."
The results from the Keck instrument were combined with data from the Spitzer Space Telescope and the Very Large Telescope Interferometer in Chile to create the final data set.
Beyond observing dust discs orbiting faraway stars, the nuller's observations may help scientists in the future directly image extrasolar planets. "If you are looking for planets, dust can be a kind of background noise." said Kuchner.
"Understanding the dust clouds around nearby stars can help us compensate for that noise in future observations."
For more information about the Keck interferometer, click here.
JPL manages the Keck Interferometer for NASA's Science Mission Directorate, Washington. The W.M. Keck Observatory is funded by California Institute of Technology, the University of California and NASA, and is managed by the California Association for Research in Astronomy, Kamuela, Hawaii.
Written by Joshua Rodriguez/PlanetQuest
