Binary asteroid IAU announcement telegram

(2019) VAN ALBADA
V. Benishek, Belgrade Astronomical Observatory; P. Pravec, Ondrejov
Observatory; R. Durkee, Shed of Science South Observatory, Pontotoc, TX,
U.S.A.; M. Husarik, M. Pikler, G, Cervak, and D. Tomko, Skalnate Pleso
Observatory; B. Christmann, Soucieu-en-Jarrest, France; A. Aznar, Isaac
Aznar Observatory, Alcublas, Valencia, Spain; D. Pray, Sugarloaf Mountain
Observatory, South Deerfield, MA, U.S.A.; F. Pilcher, Organ Mesa Observatory,
Las Cruces, NM, U.S.A.; V. Chiorny, Kharkiv Observatory; and A. Marchini, R..
Papini, and F. Salvaggio, Dipartimento di Scienze Fisiche, Della Terra e
Dell’Ambiente, University of Siena, report that photometric observations
taken with a 0.35-m telescope at the Sopot Observatory in Serbia, a 0.50-m
telescope at the Shed of Science South Observatory, a 0.61-m telescope at
the Skalnate Pleso Observatory, 0.28-m telescope at Soucieu-en-Jarrest, a
0.35-m telescope at the Isaac Aznar Observatory, a 0.50-m telescope at the
Sugarloaf Mountain Observatory, a 0.35-m telescope at the Organ Mesa
Observatory, a 0.70-m telescope at the Chuguev station of the Kharkiv
Observatory in Ukraine, and a 0.30-m telescope at the Astronomical
Observatory of the University of Siena during Sept. 22-Oct. 26 reveal that
minor planet (2019) is a binary system with an orbital period of 17.982 ±
0.003 hr. The primary shows a period of 2.7294 ± 0.0005 hr and has a
lightcurve amplitude of 0.16 magnitude at solar phases 2-3 degrees. Mutual
eclipse/occultation events that are 0.07 to 0.12 magnitude deep indicate a
lower limit on the secondary-to-primary mean-diameter ratio of 0.26.

2019 October 30 (CBET 4689) Daniel W. E. Green

Binary asteroid IAU announcement telegram

(18303) 1980 PU
V. Benishek, Belgrade Astronomical Observatory; P. Pravec and P.
Kusnirak, Ondrejov Observatory; R. Durkee, Shed of Science South Observatory,
Pontotoc, TX, U.S.A.; D. Pray, Sugarloaf Mountain Observatory, South
Deerfield, MA, U.S.A.; V. Chiorny and O. Mikhalchenko, Kharkiv Observatory;
M. Husarik and M. Pikler, Skalnate Pleso Observatory; J. Oey, Blue Mountains
Observatory, Leura, NSW, Australia; P. Bacci and M. Maestripieri,
Astronomical Observatory, San Marcello Pistoiese, Italy; and A. Aznar, Isaac
Aznar Observatory, Alcublas, Valencia, Spain, report that photometric
observations taken with a 0.35-m telescope at the Sopot Observatory in
Serbia, a 0.50-m telescope at the Shed of Science South Observatory, a
0.50-m telescope at the Sugarloaf Mountain Observatory, a 0.70-m telescope
at the Chuguev station of the Kharkiv Observatory in Ukraine, a 0.61-m
telescope at the Skalnate Pleso Observatory, a 0.35-m telescope at the Blue
Mountains Observatory, a 0.60-m telescope at the San Marcello Pistoiese
Observatory, and a 0.35-m telescope at the Isaac Aznar Observatory during
Aug. 10-Oct. 2 reveal that minor planet (18303) is a binary system with an
orbital period of 12.270 ± 0.003 hr. The primary shows a period of
2.72627 ± 0.00010 hr and has a lightcurve amplitude of 0.10 magnitude at
solar phases 4-14 degrees, suggesting a nearly spheroidal shape. Mutual
eclipse/occultation events that are 0.05 to 0.12 magnitude deep indicate
a secondary-to-primary mean-diameter ratio of 0.24 ± 0.03.

2019 October 9 (CBET 4676) Daniel W. E. Green” [2019-10-10 07:45, Ondrejov]