Astronomers found the heaviest and purest brown dwarf to date

The heaviest brown dwarf was found by an international group of astronomers. It’s named SDSS J0104+1535, and it is located in our Galaxy’s halo – where the oldest stars reside.

Brown dwarfs are too small to fuse hydrogen to helium, but they are still far more massive than planets. This puts them as an intermediate between stars and planets.

In the constellation of Pisces, about 750 light years, SDSS J0104+1535 resides. It’s made of a gas that is  250 times “purer” than the Sun. This means that it consists of 99,99% hydrogen and helium, and just traces of other gases.

Perusing the European Southern Observatory’s “Very Large Telescope” measurements in the optical and near-infrared spectrum, astronomers classified SDSS J0104+1535 as a L-type ultra-subdwarf.

Scientists have calculated the brown dwarf formation to have occured about 10 billion years ago, and its mass is at 90 times that of Jupiter – making it the most massive brown dwarf ever observed.

The formation of brown dwarfs from such an primordial gas was just a speculation, and this discovery shows us a large population of “pure” brown dwarfs that were created at our galaxy’s birth.

The finding came from the team of  Dr Zeng Hua Zhang, from the Instutite of Astrophysics located in the Canary Islands.

“We really didn’t expect to see brown dwarfs that are this pure. Having found one though often suggests a much larger hitherto undiscovered population — I’d be very surprised if there aren’t many more similar objects out there waiting to be found.” – said the team leader Dr Zhang.

SDSS J0104+1535 has been classified as an L type ultra-subdwarf using its optical and near-infrared spectrum, measured using the European Southern Observatory’s “Very Large Telescope” (VLT). This classification was based on a scheme very recently established by Dr Zhang.