What is it about the star CFBDSIR 1458 +10B discovered in 2011?

A group of astronomers discovered in 2011 a star that is probably the coldest in the Universe. It is a brown dwarf CFBDSIR 1458+10B, whose surface temperature reaches hovering around 212 °F (100°C), it's no warmer than a freshly brewed cup of coffee.

The article explaining this finding was published in the Astrophysical Journal. To get an idea, the temperature on the surface of our star is around 10,000 °F (5500°C), that of this brown dwarf corresponds to that of the boiling point of water.

Brown dwarfs are space objects that occupy a position between the giant planets and stars. Its mass is not enough for the pressure inside it to initiate the continuous reactions of nuclear fusion.

This star is part of the binary system CFBDSIR 1458 +10 which is located at a distance of about 75 light years. Its companion, CFBDSIR 1458 +10a, has a temperature around 440 °F (226°C). The distance between the two is 3 AU and its orbital period is 30 years.

The astronomers used the data received by the Keck II telescope located in the Hawaiian Islands and the VLT (Very Large Telescope) system of the European Southern Observatory in Chile, to determine the distance between two dwarfs and their temperatures.

With these temperatures, both stars are expected to have different properties from other known brown dwarfs and more closely resemble giant exoplanets, they say "they could even have clouds of water in the atmosphere."