An Abnormally Red Brown Dwarf

On February 5th, a team of astronomers from the University of Hertfordshire, England, published a paper about the discovery of an "extremely red L dwarf". 

A brown dwarf is a star that cannot sustain hydrogen fusion in their cores and thus are usually extremely small and cold compared to most other stars.  The small size poses a problem for distinguishing between these substellar masses and planets. The L spectral class of brown dwarves are more reddish than the other classes.

The astronomers noticed this particular peculiar L dwarf from the United Kingdom Infrared Deep Sky Survey Large Area Survey and then used the VLT to attempt to determine why the star was so red.  Using some complicated sounding and probably/possibly clever techniques such as  "applying a de-reddening extinction curve to its spectrum" and not so complicated things such as "increasing optical depth", the team was able to determine that the cause of the redness is due to the composition of the star's atmosphere.  More specifically, they extrapolated that the colors of the brown dwarves will be determined by the thickness of the dust cloud.  While this may not be the most interesting topic in astronomy, findings like these help further model ultracool atmospheres in low temperature stars which are apparently not very well understood.

Source

An artist's interpretation of what an L dwarf might look like.