Electronic Telegram No. 5085
Central Bureau for Astronomical Telegrams
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Prepared using the Tamkin Foundation Computer Network


2021 DS_15
     D. J. Tholen, University of Hawaii; S. S. Sheppard, Carnegie Institution
for Science; and C. A. Trujillo, Northern Arizona University, report that
discovery images from the Subaru 8-m telescope on Mauna Kea on 2021 Feb. 17
reveal that the transneptunian minor planet 2021 DS_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".65.  The secondary was about 0.4
magnitude fainter and at position angle about 30 deg from the primary; the
r-band magnitude given with the astrometry on Feb. 17 was 22.5 (cf. MPEC
2021-Y30).  Follow-up images from the Magellan 6.5-m telescope on 2021 Mar.
9, 17, and 18 again showed the binary nature of the object with similar
characteristics as at discovery.


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      superseded by text appearing later in the printed IAU Circulars.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 5085)              Daniel W. E. Green