Quote:
Originally Posted by blink138
you would wonder how on earth they would pick that up as a wandering planet would not leave much of a "signature?"
pat
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An extract from a Web write up on this find.
Credit to the original writer ..!!
It was discovered by astronomers surveying a small clot of stars located just about 75 light years from Earth. This cluster, called AB Doradus, is a group of about 30 stars that probably formed together and are still moving through space together, like a swarm of bugs. Using various measurements of the stars themselves, astronomers have determined the stars are young: less than 200 million years old for sure, and possibly only a tenth that age. That may sound ancient, but compare that to the Sun’s age of 4.6 billion years and you see the AB Dor stars are actually pretty sprightly.
The astronomers probed the cluster using a telescope sensitive to infrared light. They were specifically looking for objects of low mass, which, at the cluster’s age, tend to glow brightly at those wavelengths, still warm from their recent formation. What they found was CFBDSIR2149.
If it is indeed a member of the cluster, then it’s almost certainly a planet-like object. It would have a mass about four to seven times that of Jupiter: Earth-like, it ain’t. It’s big, but well below the mass a star would have, and still fairly safely in the range of what we call a planet. It has a temperature of about 450 degrees Celsius (850 degrees Fahrenheit), which is pretty warm by human standards, but even the smallest, coolest stars are hotter. Again, it looks more like a planet than a star.
But the most interesting bit is that there’s no star nearby! That is, it doesn’t appear to be orbiting a star; it’s sitting out there in the cluster, but pretty much on its own. That’s one of the reasons the astronomers could study it so well. With no close star, the object’s light was easy to see and analyze. A nearby star would’ve washed it out.
Flash ..!!
