Binary asteroid IAU announcement telegram

(3523) ARINA
V. Benishek, Belgrade Astronomical Observatory; P. Pravec, Ondrejov
Observatory; M. Husarik, Skalnate Pleso Observatory; A. Marchini,
R. Papini, and F. Salvagio, Dipartimento di Scienze Fisiche, Della Terra
e Dell’Ambiente, University of Siena; W. Cooney, Starry Night
Observatory, Columbus, TX, U.S.A.; A. Aznar, Isaac Aznar Observatory,
Alcublas, Valencia, Spain; P. Santos-Sanz, A. Sota, F. J. Aceituno,
Instituto de Astrofísica de Andalucía-CSIC, Granada, Spain, R. Goncalves and R. Durkee, Shed of
Science South Observatory, Pontotoc, TX, U.S.A., report that photometric
observations taken with a 0.35-m telescope at the Sopot Observatory in
Serbia, a 0.61-m telescope at the Skalnate Pleso Observatory, a 0.30-m
telescope at the Astronomical Observatory of the University of Siena,
a 0.23-m telescope at the WBRO Florence Observatory, a 0.50-m telescope
at the Starry Night Observatory, a 0.90-m telescope at the Sierra Nevada
Observatory IAA-CSIC and a 0.50-m telescope at the Shed of
Science South Observatory during Mar. 2-May 16 reveal that minor planet
(3523) is a binary system with an orbital period of 29.26 +/- 0.02 hr.
The primary shows a period of 2.6742 +/- 0.0001 hr and has a lightcurve
amplitude of 0.08 magnitude at solar phases 9-13 degrees, suggesting a
nearly spheroidal shape. Mutual eclipse/occultation events that are
0.06 magnitude deep indicate a lower limit on the secondary-to-primary
mean-diameter ratio of 0.24.

Binary asteroid IAU announcement telegram

(2500) ALASCATTALO
V. Benishek, Belgrade Astronomical Observatory; P. Pravec, Ondrejov
Observatory; F. Pilcher, Organ Mesa Observatory, Las Cruces, NM, U.S.A.; A.
Marchini, R. Papini, and F. Salvaggio, Dipartimento di Scienze Fisiche, Della
Terra e Dell’Ambiente, University of Siena; J. Oey, Blue Mountains
Observatory, Leura, NSW, Australia; D. Pray, Sugarloaf Mountain Observatory,
South Deerfield, MA, U.S.A.; R. Durkee, Shed of Science South Observatory,
Pontotoc, TX, U.S.A.; W. Cooney, J. Gross, and D. Terrell, Sonoita Research
Observatory, Sonoita, AZ, U.S.A.; R. Goncalves, Linhaceira Observatory,
Tomar, Portugal; A. Aznar, Isaac Aznar Observatory, Alcublas, Valencia,
Spain; C. Odden, Phillips Academy, Andover, MA, U.S.A.; and J. Kemp,
Middlebury College, Middlebury, VT, U.S.A., report that photometric
observations taken with a 0.35-m telescope at the Sopot Observatory in Serbia,
a 0.35-m telescope at the Organ Mesa Observatory, a 0.30-m telescope at the
Astronomical Observatory of the University of Siena, a 0.35-m telescope at the
Blue Mountains Observatory, a 0.50-m telescope at the Sugarloaf Mountain
Observatory, a 0.50-m telescope at the Shed of Science South Observatory, a
0.50-m telescope at the Sonoita Research Observatory, a 0.35-m telescope at
the Linhaceira Observatory, a 0.35-m telescope at the Isaac Aznar Observatory,
and a 0.50-m telescope at the Mittelman Observatories at New Mexico Skies
during Mar. 20-May 19 reveal that minor planet (2500) is a binary system
with an orbital period of 169.1 ± 0.3 hr. The primary shows a period of
2.75123 ± 0.00009 hr and has a lightcurve amplitude of 0.19 magnitude at
solar phases 2-17 degrees, suggesting a nearly spheroidal shape. Mutual
eclipse/occultation events that are 0.15 to 0.27 magnitude deep indicate a
secondary-to-primary mean-diameter ratio of 0.39 ± 0.02.

2020 June 7 (CBET 4791) Daniel W. E. Green [2020-06-08 06:24, Ondrejov]

Binary asteroid IAU announcement telegram

(1480) AUNUS
V. Benishek, Belgrade Astronomical Observatory; P. Pravec, Ondrejov
Observatory; J. Oey, Blue Mountains Observatory, Leura, NSW, Australia;
R. Durkee, Shed of Science South Observatory, Pontotoc, TX, U.S.A.; C. Odden,
Phillips Academy, Andover, MA, U.S.A.; W. Cooney, Starry Night Observatory,
Columbus, TX, U.S.A.; J. Kemp, Middlebury College, Middlebury, VT, U.S.A.;
D. Pray, Sugarloaf Mountain Observatory, South Deerfield, MA, U.S.A.; J.
Gross and D. Terrell, Sonoita Research Observatory, Sonoita, AZ, U.S.A.; 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 0.35-m telescope at the Blue Mountains Observatory,
a 0.50-m telescope at the Shed of Science South Observatory, a 0.50-m
telescope at the Phillips Academy Observatory, a 0.50-m telescope at the
Starry Night Observatory, a 0.50-m telescope at the Mittelman Observatories
at New Mexico Skies, a 0.50-m telescope at the Sugarloaf Mountain
Observatory, a 0.50-m telescope at the Sonoita Research Observatory, and a
0.35-m telescope at the Isaac Aznar Observatory during Mar. 21-May 19 reveal
that minor planet (1480) is a binary system with an orbital period of 19.714
± 0.003 hr. The primary shows a period of 5.1600 ± 0.0002 hr and has a
lightcurve amplitude of 0.16 magnitude at solar phases 2-18 degrees,
suggesting a nearly spheroidal shape. Mutual eclipse/occultation events that
are 0.09 to 0.20 magnitude deep indicate a lower limit on the secondary-to-
primary mean-diameter ratio of 0.30.

The changing rotational lightcurve of Varuna and evidence for a close-in satelite

From CCD observations carried out with different telescopes, we present short-term photometric measurements of the large trans-Neptunian object Varuna in 10 epochs, spanning around 19 years.

We observe that the amplitude of the rotational light curve has changed considerably during this period of time from 0.41 to 0.55 mag… We propose that these changes in the rotational light-curve shape are due to a large and close-in satellite whose rotation induces the additional periodicity. The peak-to-valley amplitude of this oscillation is in the order of 0.04 mag. We estimate that the satellite orbits Varuna with a period of 11.9819 hr (or 23.9638 hr).

The Astrophysical Journal Letters, 883:L21 (7pp), 2019 September 20 © 2019. The American Astronomical Society.

Download paper

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]

Asteroid pairs: a complex picture

 

In the main belt of asteroids, there exist pairs of asteroids that are on highly similar heliocentric orbits. They were discovered by Vokrouhlický and Nesvorný (2008) who showed that the asteroid pairs cannot be random coincidences of unrelated asteroids from the local asteroid population, but most of them must be genetically related pairs.

Being motivated by the progress in our knowledge and understanding of asteroid pairs, we underwent a thorough photometric study of a sample of nearly 100 asteroid pairs.

http://aptog.com/wp-content/uploads/2019/07/astpairscomplex_Icarus_333_pp429_463.pdf

Binary asteroid discovery IAU announcement

IAU CBET 4634

(1344) CAUBETA
B. Christmann, Soucieu-en-Jarrest, France; P. Pravec, K. Hornoch, H.
Kucakova, and P. Kusnirak, Ondrejov Observatory; D. Pray, Sugarloaf Mountain
Observatory, South Deerfield, MA, U.S.A.; V. Benishek, Belgrade Astronomical
Observatory; R. Montaigut and A. Leroy, OPERA Observatory, France; A. Marchini,
R. Papini, and F. Salvaggio, Dipartimento di Scienze Fisiche, Della Terra e
Dell’Ambiente, University of Siena; A. Aznar Macias, Astronomia Para Todos 
Observatories Group, Spain; and M. Serra-Ricart and J. Licandro, Instituto de
Astrofisica de Canarias, report that photometric observations obtained with a
0.20-m telescope at Soucieu-en-Jarrest, a 0.65-m telescope at Ondrejov
Observatory, a 0.50-m telescope at the Sugarloaf Mountain Observatory, a
0.35-m telescope at the Sopot Observatory in Serbia, a 0.20-m telescope at
the OPERA Observatory, a 0.30-m telescope at the Astronomical Observatory of
the University of Siena, and a 0.45-m telescope at Observatorio del Teide
during Feb. 17-Mar. 26 reveal that minor planet (1344) is a binary system
with an orbital period of 42.40 ± 0.03 hr. The primary shows a period of
3.12219 ± 0.00006 hr and has a lightcurve amplitude of 0.43 mag at solar
phases 5-9 deg. Mutual eclipse/occultation events that are 0.08 to 0.16
magnitude deep indicate a lower limit on the secondary-to-primary mean-
diameter ratio of 0.27. The mean absolute magnitude in the Cousins R
photometric system is H_R = 12.79 ± 0.06, assuming the phase relation slope
parameter G = 0.24 ± 0.11.

2019 June 3 (CBET 4634) Daniel W. E. Green» [2019-06-04 07:28, Ondrejov]

(20882) 2000 VH57: AN INNER MAIN-BELT BINARY ASTEROID

http://aptog.com/wp-content/uploads/2019/04/2019MPBu___46__164W.pdf

CCD photometric observations of the inner main-belt asteroid (20882) 2000 VH57 were made from 2018 Sept. 15 through Oct. 20. Analysis of the data showed that the asteroid is binary with a primary rotational period of 2.5586 hr and a satellite orbital period of 32.81 hr. Mutual eclipse/occultation events indicate a lower limit on the secondary-to-primary mean diameter ratio (Ds/Dp) of 0.23. During the period of observations, the primary and secondary lightcurves evolved as the viewing aspect changed. In particular, the depth of the secondary event increased significantly towards the end of the observations.

(31345) 1998 PG: A BINARY NEAR-EARTH ASTEROID?

(31345) 1998 PG: A BINARY NEAR-EARTH ASTEROID?

Photometric observations of the near-Earth asteroid (31345) 1998 PG by Pravec et al. (2000) found a rotation period of 2.51620 h. Also found was a secondary period of 7.0035 h, or the double-period of 14.007 h, possibly indicating an additional body in the system.

An extended campaign by the authors in 2018 lead to a similar primary period of 2.5168 h. However, instead of a 7-hour secondary period, one of about 16 hours was found with the lightcurve showing apparent mutual events (occultations and/or eclipses).

Physical properties of PHA 2014 JO25 from a worldwide observational campaign

https://academic.oup.com/mnras/advance-article/doi/10.1093/mnras/sty3250/5228750?guestAccessKey=2ed14d75-36d3-4ea8-856f-8b3d0d813ca9

The study of minor planets is motivated both by fundamental science of Solar System origins (some of these bodies contain the most pristine materials from the early ages of the planetary nebula), and by practical reasons concerning space exploration and impact frequency with Earth. Among minor bodies, near-Earth asteroids (NEAs) are a particularly important group: these objects are nearby the Earth’s orbit and they represent both resources and hazards to humans. This is the case of 2014 JO25.

Lightcurve of NEA 1993 RA

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.

2018MPBu___45___96V

Lightcurve analysis of NEA (190166) 2005 UP156: A new fully-synchronous binary

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
with caution.

2017MPBu___44__324W

Photometric analysis and physical parameters for six Mars-crossing and ten main-belt asteroids from APT Observatory Group: 2017 April- September

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.

2018MPBu___45___92A

Binary asteroid discovery IAU announcement

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

http://www.cbat.eps.harvard.edu/cbet/RecentCBETs.html

Binary asteroid discovery IAU announcement

IAU CBET 4565

(100015) 1989 SR7
V. Benishek, Belgrade Astronomical Observatory; P. Pravec, H. Kucakova,
K. Hornoch, and P. Kusnirak, Ondrejov Observatory; J. Oey, Blue Mountains
Observatory, Leura, NSW, Australia; R. Groom, Darling Range Observatory,
Perth, Western Australia; A. Aznar, Astronomia Para Todos Observatories Group,
Spain; and A. Sota, Observatorio de Sierra Nevada, Instituto de Astrofisica de
Andalucia-CSIC, report that photometric observations taken with a 0.35-m
telescope at the Sopot Observatory in Serbia, a 0.65-m telescope at the
Ondrejov Observatory, a 0.35-m telescope at the Blue Mountains Observatory, a
0.30-m telescope at the Darling Range Observatory, and a 0.90-m telescope at
the Sierra Nevada Observatory during Sept. 9-Oct. 12 reveal that minor planet
(100015) is a binary system with an orbital period of 20.65 ± 0.01 hr. The
primary shows a period of 2.4172 ± 0.0002 hr and has a lightcurve amplitude
of 0.05 mag at solar phases 7-22 degrees, suggesting a nearly spheroidal
shape. Mutual eclipse/occultation events that are 0.13 to 0.21 magnitude deep
indicate a secondary-to-primary mean-diameter ratio of 0.35 ± 0.02. The
mean absolute R magnitude in the Cousins system is H_R = 15.55 ± 0.11,
assuming the phase-relation slope parameter G = 0.24 ± 0.11.

2018 October 23,  Daniel W. E. Green

http://www.cbat.eps.harvard.edu/cbet/RecentCBETs.html

Binary asteroid discovery IAU announcement

IAU CBET 4563

(2178) KAZAKHSTANIA
V. Benishek, Belgrade Astronomical Observatory; P. Pravec, H. Kucakova,
and K. Hornoch, Ondrejov Observatory; V. Chiorny, Kharkiv Observatory; F.
Pilcher, Organ Mesa Observatory, Las Cruces, NM, U.S.A.; A. Aznar, Astronomia
Para Todos Observatories Group, Spain; and V. Casanova, Observatorio de Sierra
Nevada, Instituto de Astrofisica de Andalucia, Consejo Superior de
Investigaciones Cientificas, report that photometric observations taken with a
0.35-m telescope at the Sopot Observatory in Serbia, a 0.65-m telescope at the
Ondrejov Observatory, a 0.70-m telescope at the Chuguev station of the Kharkiv
Observatory in Ukraine, a 0.35-m telescope at the Organ Mesa Observatory, and
a 0.90-m telescope at Sierra Nevada Observatory during Sept. 18-Oct. 15 reveal
that minor planet (2178) is a binary system with an orbital period of 18.504
± 0.006 hr. The primary shows a period of 3.0183 ± 0.0002 hr and has a
light-curve amplitude of 0.31 mag at solar phases 8-11 degrees. Mutual
eclipse/occultation events that are 0.07 to 0.15 magnitude deep indicate a
secondary-to-primary mean-diameter ratio of 0.26 ± 0.02. The secondary
appears synchronous and has a light-curve amplitude (in the combined primary
plus secondary light curve) of 0.02 mag, suggesting a moderately elongated
shape with the equatorial axis ratio of 1.3 ± 0.1.

http://www.cbat.eps.harvard.edu/cbet/RecentCBETs.html

Density and axis-size relationship of five main-belt asteroids: 2017 January-March

Despite many decades of minor planet studies focused
on external and dynamical properties, there are still
hundreds of asteroids that have never been measured.
Presented here are the results of photometric analysis
applied to five main-belt asteroids. In addition to
calculating rotation period, axis ratios assuming a simple
ellipsoidal shape and the estimated minimum density of
each asteroid are reported.

2017MPBu___44__276A

Associated tables:

T1
T2

Binary asteroid discovery IAU announcement

IAU CBET nº4321

(27675) 1981 CH
D. Pray, Sugarloaf Mountain Observatory, South Deerfield, MA, U.S.A.;
P. Pravec, H. Kucakova, K. Hornoch, P. Kusnirak and J. Vrastil, Ondrejov
Observatory; A. Carbognani, Astronomical Observatory of the Aosta Valley
Autonomous Region, Italy; A. Aznar, Isaac Aznar Observatory, Centro
Astronomico del Alto Turia, Aras de los Olmos, Spain; V. Benishek, Belgrade
Astronomical Observatory; W. Cooney and J. Gross, Sonoita Research
Observatory, Sonoita, AZ, U.S.A.; D. Terrell, Southwest Research Institute;
and R. Montaigut and A. Leroy, OPERA Observatory, France, report that
photometric observations taken with a 0.50-m telescope at the Sugarloaf
Mountain Observatory, a 0.65-m telescope at the Ondrejov Observatory, a
0.81-m telescope at the Observatory of the Aosta Valley Autonomous Region,
a 0.35-m telescope at the Isaac Aznar Observatory, a 0.35-m telescope at the
Sopot Observatory in Serbia, a 0.50-m telescope at the Sonoita Research
Observatory, and a 0.20-m telescope at the OPERA Observatory during 2016 Dec.
21-2017 Feb. 1 reveal that minor planet (27675) is a binary system with an
orbital period of 120.1 ± 0.4 hr. The primary shows a period of 2.9661 ±
0.0004 hr and has a lightcurve amplitude of 0.11 mag at solar phases 9-13
degrees, suggesting a nearly spheroidal shape. Mutual eclipse/occultation
events that are 0.04- to 0.06-magnitude deep indicate a lower limit on the
secondary-to-primary mean-diameter ratio of 0.20.

Binary asteroid discovery IAU announcement

IAU CBET nº4523

(15745) YULIYA
A. Aznar, Observatorio Isaac Aznar, Aras de los Olmos, Spain;
O. Vaduvescu, Isaac Newton Group (ING) and Instituto de Astrofisica de
Canarias (IAC), Spain; T. Wilson, Isaac Newton Group (ING), University
College London (UCL), U.K.; T. Zegmott, Isaac Newton Group (ING),
University of Kent, U.K., and P. Pravec, Ondrejov Observatory, report
that photometric observations taken within the European Near Earth
Asteroids Research (EURONEAR) program with a 1.2-m telescope at the
Mercator Observatory, La Palma, Canary Island, Spain, during
Apr. 26-May 6 reveal that minor planet (15745) is a binary system with
an orbital period of 15.63 +/- 0.02 hr.  The primary shows a period of
3.2486 +/- 0.0003 hr and has a lightcurve amplitude of 0.10 mag at solar
phases 35.1-35.2 degrees, suggesting a nearly spheroidal shape.  Mutual
eclipse/occultation events that are 0.15- to 0.21-magnitude deep indicate
a lower limit on the secondary-to-primary mean-diameter ratio of 0.43.

Binary asteroid discovery IAU announcement

IAU CBET nº4517:

(17700) 1953 XU_1 = 1997 GM_40 = 1999 VD_53

D. Pray, Sugarloaf Mountain Observatory, South Deerfield, MA, U.S.A.;
P. Pravec, H. Kucakova, K. Hornoch, and P. Kusnirak, Ondrejov Observatory;
J. Oey, Blue Mountains Observatory, Leura, NSW, Australia; V. Benishek,
Belgrade Astronomical Observatory; A. Aznar, Astronomia Para Todos
Observatories Group, «European Near Earth Asteroids Research (EURONEAR)»,
Spain; and A. L. Comazzi, Instituto de Astrofisica de Andalucia, CSIC,
Spain, report that photometric observations obtained with a 0.50-m
telescope at the Sugarloaf Mountain Observatory, a 0.65-m telescope at the
Ondrejov Observatory, a 0.61-m, a 0.35-m and a 0.31-m telescopes at the
Blue Mountains Observatory, a 0.35-m telescope at the Sopot Observatory in
Serbia, and a 0.90-m telescope at Sierra Nevada Observatory during
Mar. 20-May 10 reveal that minor planet (17700) is a binary system with an
orbital period of 15.49 ± 0.02 hr. The primary shows a period of 3.8382
± 0.0002 hr and has a lightcurve amplitude of 0.13 mag at solar phases
8-15 degrees, suggesting a nearly spheroidal shape. Mutual
eclipse/occultation events that are up to 0.20-magnitude deep indicate a
lower limit on the secondary-to-primary mean-diameter ratio of 0.31.
There occurred two additional 0.14- to 0.18-magnitude-deep attenuations on
Mar. 20 and 25 that were not aligned with the 15.49-hr orbital period,
suggesting presence of a third body in the system. The mean absolute
magnitude of the whole system in the Cousins R photometric system is H_R =
13.98 ± 0.05 with the phase relation slope parameter G = 0.35 ± 0.05.

EURONEAR – First Lightcurves and physical properties of Near Earth Asteroids

Part of the European Near Earth Asteroids Research (EURONEAR) project, in 2014 we started a survey to observe light curves of Near Earth Asteroids (NEAs) using the available telescopes of this network. This is the first paper presenting light-curves and physical properties of 17 NEAs observed by two amateur astronomers owning small facilities located in good sites, namely a 0.36 m telescope at Isaac Aznar Observatory (Aras de los Olmos, Spain) and a 0.61 m telescope at Blue Mountain Observatory (Leura, Australia). We confirm most recent or older results and find new ones.

https://arxiv.org/abs/1801.09420

Binary asteroid discovery IAU announcement

IAU CBET nº4440:

(10132) LUMMELUNDA 
V. Benishek, Belgrade Astronomical Observatory; P. Pravec, P. Kusnirak, 
and H. Kucakova, Ondrejov Observatory; F. Pilcher, Organ Mesa Observatory, 
Las Cruces, NM, U.S.A.; D. Pray, Sugarloaf Mountain Observatory, South 
Deerfield, MA, U.S.A.; R. Durkee, Shed of Science Observatory, Minneapolis, 
MN, U.S.A.; A. Aznar, Astronomia Para Todos Observatories Group, «European 
Near Earth Asteroids Research» (EURONEAR) project, Spain; and F. J. Aceituno, 
Observatorio de Sierra Nevada, report that photometric observations taken 
with a 0.35-m telescope at the Sopot Observatory in Serbia, a 0.65-m telescope 
at the Ondrejov Observatory, a 0.35-m at the Organ Mesa Observatory, a 0.50-m 
telescope at the Sugarloaf Mountain Observatory, a 0.50-m telescope at the 
Shed of Science Observatory, and a 0.9-m telescope at the Observatorio de 
Sierra Nevada during Aug. 27-Sept. 28 reveal that minor planet (10132) is a 
binary system with an orbital period of 22.44 ± 0.01 hr. The primary shows 
a period of 2.5099 ± 0.0001 hr and has a lightcurve amplitude of 0.11 mag 
at solar phases 2-3 degrees, suggesting a nearly spheroidal shape. Mutual 
eclipse/occultation events that are 0.08- to 0.16-magnitude deep indicate a 
lower limit on the secondary-to-primary mean-diameter ratio of 0.28.