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BOSS Ultracool Dwarfs
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BOSS Ultracool Dwarfs: Schmidt et al. (2014) OSU Astronomy Coffee Brief

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RE: Ultracool Dwarfs
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Coolest brown dwarf discovered

The coolest stars in the galaxy have finally come out of hiding. Astronomers using data from NASA's Wide-field Infrared Survey Explorer (WISE) have found six chilly almost-stars called Y dwarfs, which had been hunted unsuccessfully for more than a decade.
Y dwarfs are the coldest class of brown dwarfs, star-like bodies that are too low-mass to fuse hydrogen in their cores. These "failed stars" don't burn the way stars like our sun do, meaning they do not emit visible wavelengths that most telescopes can spot.

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Title: Maximum Reduced Proper Motion Method: Detection of New Nearby Ultracool Dwarfs
Authors: N. Phan-Bao (HCMIU, Vietnam National University)

In this paper, we describe how to use the Maximum Reduced Proper Motion method (Phan-Bao et al. 2003) to detect 57 nearby L and late-M dwarfs (d_phot <= 30 pc): 36 of them are newly discovered. Spectroscopic observations of 43 of the 57 ultracool dwarfs were previously reported in Martin et al. (2010). These ultracool dwarfs were identified by colour criteria in ~5,000 square degrees of the DENIS database and then further selected by the method for spectroscopic follow-up to determine their spectral types and spectroscopic distances. We also report here our newly measured proper motions of these ultracool dwarfs from multi-epoch images found in public archives (ALADIN, DSS, 2MASS, DENIS), with at least three distinct epochs and time baselines of 2 to 46 years.

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