In just three years, the cloud of dust surrounding a young star has disappeared, indicating that there’s something wrong with our current ideas of planet formation.
It may mean that planets can form much more quickly than previously thought or, alternatively, that stars harboring planets could be far more numerous.
“The most commonly accepted time scale for the removal of this much dust is in the hundreds of thousands of years, sometimes millions,” says Inseok Song, assistant professor of physics and astronomy at the University of Georgia.
“What we saw was far more rapid, and has never been observed or even predicted. It tells us that we have a lot more to learn about planet formation.”
TG Daily — The scientists examined data from the Infrared Astronomical Satellite, or IRAS, which surveyed more than 96 percent of the sky in 1983. The star, known as TYC 8241 2652 1, is located in the Scorpius-Centaurus stellar nursery, and was originally surrounded by a cloud of dust that was identifiable by its distinctive radiation of infrared energy.
Examination in 2008 using a mid-infrared imager at the Gemini South Observatory in Chile showed the same pattern. But when observations were repeated a year later, the team discovered that infrared emission had dropped by nearly two-thirds.
And when NASA’s Wide-field Infrared Survey Explorer, or WISE, took a look in 2010, the dust had mostly disappeared.
“It’s as if you took a conventional picture of the planet Saturn today and then came back two years later and found that its rings had disappeared,” says Ben Zuckerman of UC Los Angeles.
The researchers have several different explanations – but not one fits with conventional thinking about planet formation.Continue Reading on www.tgdaily.com