Discovery of a Binary Brown Dwarf at 2 pc from the Sun
Abstract
I am using multi-epoch astrometry from the Wide-field Infrared Survey Explorer (WISE) to search for new members of the solar neighborhood via their high proper motions. Through this work, I have identified WISE J104915.57-531906.1 as a high proper motion object and have found additional detections in images from the Digitized Sky Survey, the Two Micron All-Sky Survey, and the Deep Near-Infrared Survey of the Southern Sky. I have measured a parallax of 0.''496 ± 0.''037 (2.0 ± 0.15 pc) from the astrometry in these surveys, making WISE J104915.57-531906.1 the third closest system to the Sun. During spectroscopic observations with the Gemini Multi-Object Spectrograph at Gemini Observatory, an i-band acquisition image resolved it as a 1.''5 (3 AU) binary. A spectrum was collected for the primary, which I classify as L8 ± 1. The secondary is probably near the L/T transition as well given that it is only modestly fainter than the primary (∆i = 0.45 mag).
Based on data from the Wide-field Infrared Survey Explorer, Gemini Observatory, the Two Micron All-Sky Survey, the Deep Near-Infrared Survey of the Southern Sky, and the Digitized Sky Survey.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- April 2013
- DOI:
- arXiv:
- arXiv:1303.2401
- Bibcode:
- 2013ApJ...767L...1L
- Keywords:
-
- brown dwarfs;
- infrared: stars;
- proper motions;
- solar neighborhood;
- stars: low-mass;
- Astrophysics - Astrophysics of Galaxies;
- Astrophysics - Solar and Stellar Astrophysics
- E-Print:
- Astrophysical Journal Letters, in press
