Artículo publicado en Muy Interesante en conmemoración del Día Internacional de la Materia Oscura
The near-Earth asteroid (NEA) 1993 RA was observed
with the 2.5-m Isaac Newton Telescope (INT) in full
Moon conditions for 8h total during three successive
nights (2017 Oct 3-6). The composite lightcurve could
be fit by a 3-order period P = 5.64 ± 0.01 h with
amplitude of 0.13 mag; other solutions are possible.
CCD photometric observations of the near-Earth
asteroid (190166) 2005 UP156 in 2017 May show it to
be a fully-synchronous binary with rotation and orbital
period P = 40.542 ± 0.008 h. The estimated effective
diameter ratio of the two bodies is 0.8 ± 0.1. However,
the 0.5 mag out-of-eclipse lightcurve indicates quite
elongated shapes and so the size ratio should be viewed
Lightcurves of six Mars-crossing and eight main-belt
asteroids were obtained at APT-Observatory Group
from 2017 April to September. In addition, two more
asteroids were captured in 2014 and 2015 during the
EURONEAR project. Analysis of rotation period,
lightcurve amplitude, and physical parameters (size and
axis size relationship) are presented.
We report that asteroid (24495) 2001 AV1 is a binary
asteroid. It is another candidate for the special case of
very wide binaries. The primary lightcurve has a period
of 24.083 ± 0.005 h and an amplitude 0.58 ± 0.05 mag.
and the secondary lightcurve has a period of 2.7375 ±
IAU CBET 4570
(20882) 2000 VH57
B. D. Warner, Center for Solar System Studies (CS3), Landers, CA, USA.,
A. Aznar Macias, APT Observatories Group, M. Serra-Ricart and J.
Licandro, Instituto de Astrofísica de Canarias-IAC, and P. Pravec,
Ondrejov Observatory report that photometric observations obtained with a
0.25-m telescope at the CS3 facility in Landers, CA, USA, and 0.45-m telescope
at the Canary Astrophysics Institute, from 2018 September 15 through October 20
reveal that the inner main-belt minor planet (20882) 2000 VH57 is a binary system
with an orbital period of 32.81 +/- 0.02 hr. The primary shows a period of
2.5586 +/- 0.0001 hr and has a maximum lightcurve amplitude of 0.15 mag at solar
phase angles from 19 degrees in mid-September down to 2 degrees in mid-October.
The nearly-symmetrical shape and amplitude of the lightcurve suggest that the
primary shape is near spheroidal.
2018 November 08, Daniel W. E. Green