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arXiv · 1405.7350

NEOWISE-R Observation of the Coolest Known Brown Dwarf

Edward L. Wright·Amy Mainzer·J. Davy Kirkpatrick·Frank Masci·Michael C. Cushing·James Bauer·Sergio Fajardo-Acosta·Christopher R. Gelino·Charles A. Beichman·M. F. Skrutskie·T. Grav·Peter R. M. Eisenhardt·Roc Cutri
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Abstract

The Wide-field Infrared Survey Explorer (WISE) spacecraft has been reactivated as NEOWISE-R to characterize and search for Near Earth Objects. The brown dwarf WISE J085510.83-071442.5 has now been reobserved by NEOWISE-R, and we confirm the results of Luhman (2014b), who found a very low effective temperature ($\approx 250$ K), a very high proper motion (8.1 +/- 0.1 arcsec/yr) , and a large parallax (454 +/- 45 mas). The large proper motion has separated the brown dwarf from the background sources that influenced the 2010 WISE data, allowing a measurement of a very red WISE color of W1-W2 $> 3.9$ mag. A re-analysis of the 2010 WISE astrometry using only the W2 band, combined with the new NEOWISE-R 2014 position, gives an improved parallax of 448 +/- 33 mas and proper motion of 8.08 +/- 0.05\; arcsec/yr. These are all consistent with Luhman (2014b).

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Edward L. Wright, Amy Mainzer, J. Davy Kirkpatrick, Frank Masci, Michael C. Cushing, James Bauer, Sergio Fajardo-Acosta, Christopher R. Gelino, Charles A. Beichman, M. F. Skrutskie, T. Grav, Peter R. M. Eisenhardt, Roc Cutri. 2014-05-28. NEOWISE-R Observation of the Coolest Known Brown Dwarf. https://doi.org/10.1088/0004-6256/148/5/82

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