MASTER detection of Near-Earth Object 9 hours before the very close fly-by
ATel #5432; P. Balanutsa, M. Pruzhinskaya, D. Denisenko, V. Lipunov, E. Gorbovskoy, N. Tiurina, V. Kornilov, A. Belinski, N. Shatskiy, V. Chazov, A. Kuznetsov, V. Yecheistov, V. Vladimirov (Moscow State University, SAI), K. Ivanov, S. Yazev, N. Budnev, E. Konstantinov, O. Chuvalaev, V. Poleshchuk, O. Gress, A. Frolova (Irkutsk State University), V. Yurkov, Y. Sergienko, D. Varda, E. Sinyakov, A. Gabovich (Blagoveshchensk Educational University), A. Parkhomenko, A. Tlatov, D. Dormidontov, V. Senik (Kislovodsk Solar Station of Pulkovo Observatory), V. Krushinsky, I. Zalozhnih, A. Popov, A. Bourdanov (Ural Federal University), P. Podvorotny, V. Shumkov, S. Shurpakov (MASTER team members), H. Levato, C. Saffe (ICATE), C. Mallamaci, C. Lopez and F. Podest (OAFA)
on 29 Sep 2013; 10:48 UT
Credential Certification: Vladimir Lipunov (lipunov2007@gmail.com)
Subjects: Optical, Asteroid, Near-Earth Object
During the observations of flaring blazar 3C 454.3 in two polarization
filters, MASTER-Tunka robotic telescope (double 0.40-m f2.5 reflector
+ 4kx4k CCD, filed of view 2.1x2.1 deg) has serendipitously detected
the Fast Moving Object of 16m visible in both tubes. The object was
located near the edge of FOV, about 1 deg south of 3C 454.3. First it
was detected on the set of ten 30-sec exposures from 13:20 to 13:37 UT
with limiting magnitudes 17.3-17.5. Another set of ten 60-sec
exposures was then obtained from 13:44 to 14:05 UT with the limits
18.1-18.2 in both tubes.
The animation of ten 60-sec exposures from the Eastern tube is
uploaded to http://master.sai.msu.ru/static/NEO/MASTER-NEO-130927-Tunka-anim.gif
The object was moving at the rate of 6.2" per minute in positional
angle 71. Astrometry from 8 images was reported to Minor Planet Center
using the designation MASD91. Using Find_Orb orbit determination
software by Bill Gray (www.projectpluto.com) we have obtained the
following orbital elements:
Epoch 2013 Sep 28.0 TT = JDT 2456563.5 Earth MOID: 0.0000 Ve: 0.0772
M 343.67888 (2000.0) Ma: 0.0016
n 0.36126837 Peri. 252.01974 0.22930384 -0.97326783
a 1.95246273 Node 184.78142 0.94166328 0.22520304
e 0.6228503 Incl. 8.98491 0.24635343 0.04509218
P 2.73/996.47d H 27.7 G 0.15 q 0.73637071 Q 3.16855475
From 8 observations 2013 Sept. 27 (44.4 min); mean residual 0".295.
Absolute magnitude H=27.7 corresponds to the body of approximately 15
meters in size, similar to that of Chelyabinsk meteorite. According to
Find_Orb, the object has passed about 11300 km above the Earth surface
at 22:50 UT on 2013 Sep. 27 over the Indian ocean, approximately at
90E, 0N. The geocentric distance at the closest approach was thus
about 17700 km, or 0.00012 AU. That puts the object at Top 5 closest
approaches to the Earth by minor planets listed at
http://www.minorplanetcenter.net/iau/lists/Closest.html
At the beginning of MASTER-Tunka observations (13:20 UT, 9.5 hours
before the closest approach) the object's topocentric distance was
556433 km (1.45 Moon distances), reducing to 512345 km by 14:05 UT.
The approach velocity during MASTER-Tunka observations was 16.5 km/s.
The object could not have been discovered before Sep. 25 when its
calculated magnitude was fainter than 21m. Currently it is moving
towards the Sun and can not be observed anymore.
We have checked the NORAD database, JPL Horizons website and DASO page
and found no matches among the artificial objects. However, taking
into account very small orbital intersection distance with Mars, the
man-made origin of the object can not be excluded.
Global MASTER Robotic Net
