Electronic Telegram No. 5744
Central Bureau for Astronomical Telegrams
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(762135) 2010 WG_9
     B. Proudfoot, Florida Space Institute; W. Grundy, Northern Arizona 
University; and D. Spencer, Brigham Young University, report that the 
trans-Neptunian object (762135) is a tight, approximately equal-sized binary, 
where the secondary is 0.06 +/- 0.11 mag fainter than the primary.  The binary 
was discovered in two 300-s Hubble Space Telescope exposures taken with the 
WFC3/UVIS camera (+ F350LP filter) on 2017 Dec. 19 (HST Program 15344, P.I.
D. Jewitt).  At the time of the HST imaging, the resolved components were 
separated by 0".055 +/- 0".001 in p.a. 285 +/- 2 deg.  At the time of the 
first image (2017 Dec. 19.23218 UT), the primary was located at R.A. = 
5h56m43.56s, Decl. = +14d53'01".0 (equinox J2000.0).  This imaging confirms 
the proposed binary status of (762135), previously suggested based on its 
approximately 5.5-day rotational light curve period (Rabinowitz et al. 2013, 
A.J. 146, 17).


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                         (C) Copyright 2026 CBAT
2026 September 22                (CBET 5744)              Daniel W. E. Green