Electronic Telegram No. 5684
Central Bureau for Astronomical Telegrams
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2015 NV_28
      P. Pravec, P. Kusnirak, K. Hornoch, H. Kucakova, K. Honkova, and A.
Galad, Ondrejov Observatory; and T. Lister, Las Cumbres Observatory (LCO),
report that photometric observations taken with a 1.54-m telescope at the
La Silla station of the European Southern Observatory and two 1.0-m telescopes
at the CPT node of the LCO Network at Sutherland, South Africa, during
Mar. 16-Apr. 26 reveal that the Amor-type minor planet 2015 NV_28 is a binary
system with an orbital period of 49.2 +/- 0.2 hr.  The primary has a period of
3.582 +/- 0.002 hr and a lightcurve amplitude of 0.08 magnitude at solar
phases 28-32 degrees, suggesting a nearly spheroidal shape.  Mutual eclipse/
occultation events that are 0.14 magnitude deep indicate a lower limit on the 
secondary-to-primary mean-diameter ratio of 0.37.  The system's mean absolute 
magnitude is H = 17.89 +/- 0.05, with a phase-relation slope parameter G = 
0.12 +/- 0.10.  The color index in the Johnson-Cousins photometric system is 
(V - R) = +0.385 +/- 0.015.  These observations were taken in the framework of 
their NEOSource project, supported by the "Praemium Academiae" award from the 
Academy of Sciences of the Czech Republic.  Follow-up observations taken 
during the rest of the current apparition of the minor planet are encouraged, 
to improve the characterization of the binary system.


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                         (C) Copyright 2026 CBAT
2026 May 4                       (CBET 5684)              Daniel W. E. Green