A brown dwarf star, touted to be the coldest of its kind was located only 7.2 light-years away, making it the fourth closest system to the Sun.
The star is believed to be as frosty as Earth's North Pole and has been named WISE J085510.83-071442.5. The discovery was made by a Penn State University astronomer using NASA's Wide-field Infrared Survey Explorer (WISE) and Spitzer Space Telescopes.
"It is very exciting to discover a new neighbor of our solar system that is so close," said Kevin Luhman, an associate professor of astronomy and astrophysics at Penn State in a press statement. "In addition, its extreme temperature should tell us a lot about the atmospheres of planets, which often have similarly cold temperatures."
As interesting as the discovery is, astronomers clarified that the cosmic body is unlikely to become an appealing destination for human space travel in the future as any planet orbiting this star is likely to be too cold to visit.
The newfound star has temperatures between minus 48 to minus 13 degrees Celsius. This is quite surprising because previous brown dwarfs discovered by WISE and Spitzer, were about room temperature. The discovery was made during one of WISE's two surveys that scan the entire ski using infrared light. Some areas of the sky are observed three or more times.
Brown dwarfs are difficult to detect because even though they start off as stars, they lack the mass to burn nuclear fuel and radiate starlight. Using infrared light makes it easier to detect these stars. Most often they remain invisible to telescopes because there is no visible light detected. However, infrared light helps detect their thermal glow, no matter how feeble it may be.
WISE J085510.83-071442.5 has a mass three to ten times that of Jupiter. This low mass led researchers to speculate whether the object was a gas giant similar to Jupiter that was ejected from its star system. A further analysis helped researchers zero down on the hypothesis that the celestial body was a brown dwarf. If the findings are accurate, WISE J085510.83-071442.5 may be one of the least massive brown dwarfs known.
In March 2013, Luhman also discovered two warmer brown stars that were said to be the closest star system discovered since 1916.
"It is remarkable that even after many decades of studying the sky, we still do not have a complete inventory of the Sun's nearest neighbors," said Michael Werner, the project scientist for Spitzer at NASA's Jet Propulsion Laboratory (JPL), which manages and operates Spitzer. "This exciting new result demonstrates the power of exploring the universe using new tools, such as the infrared eyes of WISE and Spitzer."
