Coldest star in space discovered
Imagine a star as frosty as the earth's North Pole!
It is true as a Penn State University astronomer using NASA's Wide-field Infrared Survey Explorer (WISE) and Spitzer Space Telescopes has discovered a "brown dwarf" star that appears to be the coldest of its kind.
The star has been named WISE J085510.83-071442.5.
The dwarf star has a chilly temperature between minus minus 48 to minus 13 degrees Celsius. Previous record holders for coldest brown dwarfs were also found by WISE and Spitzer and were about room temperature.
The dwarf star is estimated to be three to 10 times the mass of Jupiter.
With such a low mass, it could be a gas giant similar to Jupiter that was ejected from its star system.
Images from the space telescopes pinpoint that the star is about 7.2 light-years away from the sun making it the fourth closest system to it.
"It is very exciting to discover a new neighbour of our solar system that is so close," said Kevin Luhman, an associate professor of astronomy and astrophysics at Penn State.
The extreme temperature of the dwarf star should tell us a lot about the atmospheres of planets, which often have similarly cold temperatures.
Such dwarf stars start their lives like stars, as collapsing balls of gas, but don't have the mass to burn nuclear fuel and radiate starlight.
"However, despite its proximity to our solar system, the dwarf star is not an ideal destination for human space travel in the distant future as any planets that might orbit it would be much too cold to support life as we know it," Luhman maintained.
Scientists estimate it is probably a brown dwarf rather than a planet since brown dwarfs are known to be fairly common.
If so, it is one of the least massive brown dwarfs known.
(Posted on 26-04-2014)