J/AJ/158/159 Astrometric positions for (84922) 2003 VS2 (Benedetti-Rossi+, 2019)
The trans-Neptunian object (84922) 2003 VS2 through stellar occultations.
Benedetti-Rossi G., Santos-Sanz P., Ortiz J.L., Assafin M., Sicardy B.,
Morales N., Vieira-Martins R., Duffard R., Braga-Ribas F., Rommel F.L.,
Camargo J.I.B., Desmars J., Colas A.F., Vachier F., Alvarez-Candal A.,
Fernandez-Valenzuela E., Almenares L., Artola R., Baum T.-P., Behrend R.,
Berard D., Bianco F.B., Brosch N., Ceretta A., Colazo C.A.,
Gomes-Junior A.R., Ivanov V.D., Jehin E., Kaspi S., Lecacheux J., Maury A.,
Melia R., Moindrot S., Morgado B., Opitom C., Peyrot A., Pollock J.,
Pratt A., Roland S., Spagnotto J., Tancredi G., Teng J.-P., Cacella P.,
Emilio M., Feys F., Gil-Hutton R., Jacques C., Machado D.I., Malacarne M.,
Manulis I., Milone A.C., Rojas G., Sfair R.
<Astron. J., 158, 159-159 (2019)>
=2019AJ....158..159B 2019AJ....158..159B (SIMBAD/NED BibCode)
ADC_Keywords: Solar system ; Minor planets ; Positional data
Keywords: Kuiper Belt
Abstract:
We present results from three world-wide campaigns that resulted in the
detections of two single-chord and one multi-chord stellar occultations
by the plutino object (84922) 2003 VS2. From the single-chord
occultations in 2013 and 2014 we obtained accurate astrometric positions
for the object, while from the multi-chord occultation on 2014 November 7,
we obtained the parameters of the best-fitting ellipse to the limb of
the body at the time of occultation. We also obtained short-term photometry
data for the body in order to derive its rotational phase during the
occultation. The rotational light curve present a peak-to-peak amplitude of
0.141±0.009 mag. This allows us to reconstruct the 3D shape of the body,
with principal semi-axes of a=313.8±7.1 km, b=265.5-9.8+8.8 km, and
c=247.3-43.6+26.6 km, which is not consistent with a Jacobi triaxial
equilibrium figure. The derived spherical volume equivalent diameter of
548.3-44.6+29.5 km is about 5% larger than the radiometric diameter
of 2003 VS2 derived from Herschel data of 523±35 km, but still
compatible with it within error bars. From those results we can also derive
the geometric albedo (0.123-0.014+0.015) and, under the assumption that
the object is a Maclaurin spheroid, the density ρ=1400-300+1000
for the plutino. The disappearances and reappearances of the star during
the occultations do not show any compelling evidence for a global
atmosphere considering a pressure upper limit of about 1 microbar for a
pure nitrogen atmosphere, nor secondary features (e.g., rings or satellite)
around the main body.
Description:
Astrometric updates of the candidate stars (and the TNO when possible) were
performed using several telescopes close to the dates of events in Brazil
at the Pico dos Dias Observatory (Perkin Elmer 1.6 m, Boller & Chivens
0.6 m, and ZEISS 0.6 m), in Spain at the Calar Alto Observatory (1.23 m
and 2.2 m telescopes), at the Sierra Nevada Observatory (1.5 m telescope),
and at the Observatorio de La Hitta (77 cm telescope), and in France
at Pic du Midi (T100 cm telescope) so to reduce systematic errors caused
by the reference catalogs. Astrometric positions obtained for VS2 with
those observations are listed on Table 3.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table3.dat 50 57 Astrometric positions for VS2
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See also:
B/astorb : Orbits of Minor Planets (Bowell+ 2009)
J/A+A/505/1283 : (84922) 2003 VS2 differential light curve (Duffard+, 2009)
J/A+A/522/A93 : Short-term variability of 29 minor planets (Thirouin+, 2010)
J/A+A/561/A37 : Prediction of stellar occultations 2012.5-2014
(Camargo+, 2014)
Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 18 A18 "date" Date Date of observation (in decimal days)
20- 21 I2 deg RAd Degree of Right Ascension (ICRS)
23- 24 I2 arcmin RAm Arcminute of Right Ascension (ICRS))
26- 32 F7.4 arcsec RAs Arcsecond of Right Ascension (ICRS)
33 A1 --- DE- Sign of the Declination (ICRS)
34- 35 I2 deg DEd Degree of Declination (ICRS)
37- 38 I2 arcmin DEm Arcminute of Declination (ICRS)
40- 46 F7.4 arcsec DEs Arcsecond of Declination (ICRS)
48- 50 A3 --- Site IAU code (1)
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Note (1): IAU code defined as follows:
493 = In Spain at the Calar Alto Observatory (1.23 m and 2.2 m telescopes);
586 = In France at Pic du Midi (T100 cm telescope);
I95 = At the Observatorio de La Hitta (77 cm telescope);
J86 = At the Sierra Nevada Observatory (1.5 m telescope).
Positions obtained with the ESO 2p2 telescope - IAU code 809 - under mission
090.C-0118(A) are published in Camargo et al. (2014, J/A+A/561/A37).
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History:
From electronic version of the journal
(End) Tiphaine Pouvreau [CDS] 02-Dec-2019