Electronic Telegram No. 5086
Central Bureau for Astronomical Telegrams
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2021 DM_15
     C. A. Trujillo, Northern Arizona University; S. S. Sheppard, Carnegie
Institution for Science; and D. J. Tholen, University of Hawaii, report that
discovery images from the Subaru 8-m telescope on Mauna Kea on 2021 Feb. 17
reveal that the transneptunian minor planet 2021 DM_15 is a binary system.
The primary and secondary were separately resolved in two images and were
measured to have a mean separation of 0".4 in 0".6 seeing.  The secondary was
about 0.3 magnitude fainter and at position angle about 130 deg from the
primary; the reported r-band magnitude on Feb. 17 was 23.6-23.8 (cf. MPEC
2021-Y09).  Follow-up images from the Magellan 6.5-m telescope on 2021 Mar.
17 again showed the binary nature of the object with similar characteristics
as at discovery, with the secondary some 0.5 mag fainter than the primary
(with the overall magnitude gien as r = 23.9).


NOTE: These 'Central Bureau Electronic Telegrams' are sometimes
      superseded by text appearing later in the printed IAU Circulars.

                         (C) Copyright 2021 CBAT
2021 December 21                 (CBET 5086)              Daniel W. E. Green