Learn More about the Coldest Brown Dwarf Star in the Universe
Learn More about the Coldest Brown Dwarf Star in the Universe
A brown dwarf star is being cited as the coldest star in the universe. Located within 7.2 light years from the earth, this star is the fourth closest system to the sun. This star has been labelled as WISE J085510.83-071442.5 and it is believed to be as cold as the North Pole of the earth. The discovery of this star was made by researchers from Penn State University. The astronomers used NASA’s Wide Field Infrared Survey Explorer and Spitzer Space Telescopes for this discovery.
Kevin Luhman who is the associate professor of astrophysics and astronomy at this university had indicated that the extreme temperature of this star also tells us a lot about the atmosphere of the planets that are as cold. However, experts opine that any planet circling this star would be too cold for human visit. An interesting facet of this star is that it has temperatures ranging from minus 48 to minus 130 Celsius. Previous brown dwarf stars discovered by the scientists so far have always been at room temperature.
The coldest star in the universe was discovered when NASA’s WISE (Wide Field Infrared Survey Explorer) employed surveys to scan the entire sky using infrared light. Some parts of the sky were observed many times. Brown dwarf starts lack the mass to burn nuclear fuel. They also do not have enough mass to radiate starlight. Infrared light makes it easier to investigate the features of these stars. Using telescopes to study them proves ineffective because no visible light can be detected. The reason why infrared light can be used to study brown dwarf stars is because they can study the thermal glow of these stars. Brown dwarf stars have feeble thermal glow.
The coldest star in the universe has a mass which is 3 to 10 times that of large planets such as Jupiter. Due to this reason, investigators speculated that the observed object was a giant gaseous planet like Jupiter which had been ejected from its star system. Further analysis helped researchers to zoom in on the fact that the celestial body was a brown dwarf star.
Researchers from Penn State University had discovered two brown dwarf stars that were warmer in 2013. These were thought to be the closest star systems found since the year 1916. Ever since many decades have passed when the sky has been studied by astronomers, there is still not a complete inventory of the nearest neighbours of the sun. New tools such as WISE and Spitzer may well help scientists to overcome this inadequacy.
Another interesting fact about this brown dwarf star is that it is the fourth closest system to the sun. The nearest system to the sun is a group of three stars called Alpha Centauri which is 4 light years away from the sun. Brown dwarf stars start out like regular stars much like collapsing balls of gas. But as they lack mass, they cannot radiate light. A reason why this star was detected so effectively was its fast movement in the WISE data. The closer a body is, the quicker it seems to move in images taken over a few months.
For instance, a train passing through a low lying bridge will appear to move faster than that on a high lying bridge to spectators who are underneath it. Similarly, a low flying plane appears to move more quickly than a plane flying at a higher altitude. It is this aspect of motion that worked in the favour of Penn State University researchers when they discovered this brown dwarf star.
Combined detections from NASA’s WISE and the Spitzer were taken from different points around the sum. Using the parallax effect, the measurement of the brown dwarf star’s distance from the sun was accurately taken. While brown dwarf stars are fairly common in the universe, this star is special. Compared to other brown dwarf stars, this particular one’s mass was so low that it was nearly mistaken for a planet. Clearly, discoveries like these have a lot of potential for unearthing mysteries in the universe such as the nature of star systems closest to the sun.
