CWISEP J193518.59-154620.3: An Extremely Cold Brown Dwarf in the Solar Neighborhood Discovered with CatWISE

We present the discovery of an extremely cold, nearby brown dwarf in the solar neighborhood, found in the CatWISE catalog. Photometric follow-up with Spitzer reveals that the object, CWISEP. J193518.59-154620.3, has ch1-ch2 = 3.24 +/- 0.31 mag, making it one of the reddest brown dwarfs known. Using the Spitzer photometry and the polynomial relations from Kirkpatrick et al. we estimate an effective temperature in the similar to 270-360 K range, and a distance estimate in the 5.6-10.9 pc range. We combined the WISE, NEOWISE, and Spitzer data to measure a proper motion of mu(alpha) cos delta = 337 +/- 69 mas yr(-1), mu(delta) = -50 +/- 97 mas yr(-1), which implies a relatively low tangential velocity in the range 7-22 km s(-1).