Electronic Telegram No. 5747 Central Bureau for Astronomical Telegrams Mailing address: Hoffman Lab 209; Harvard University; 20 Oxford St.; Cambridge, MA 02138; U.S.A. e-mail: cbatiau@eps.harvard.edu (alternate cbat@iau.org) URL http://www.cbat.eps.harvard.edu/index.html Prepared using the Tamkin Foundation Computer Network (501214) 2013 TC_146 B. Proudfoot, Florida Space Institute; and W. Grundy, Northern Arizona University, report that the centaur (501214) is a tight, approximately equal-sized binary, where the secondary is 0.48 +/- 0.09 magnitude 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. 13 (HST Program 15344, P.I. D. Jewitt). At the time of the HST imaging, the resolved components were separated by 0".072 +/- 0".002 in p.a. 169.1 +/- 0.1 deg. At the time of the first image (2017 Dec. 13.53097 UT), the primary was located at R.A. = 21h19m59.74s, Decl. = -13d36'19".8 (equinox J2000.0). NOTE: These 'Central Bureau Electronic Telegrams' are sometimes superseded by text appearing later in the printed IAU Circulars. (C) Copyright 2026 CBAT 2026 September 23 (CBET 5747) Daniel W. E. Green