J/A+A/584/A96 Observations of 50 TNOs and Centaurs (Desmars+, 2015)
Orbit determination of Transneptunian objects and Centaurs for the prediction
of stellar occultations.
Desmars J., Camargo J.I.B., Braga-Ribas F., Vieira-Martins R., Assafin M.,
Vachier F., Colas F., Ortiz J.L., Duffard R., Morales N., Sicardy B.,
Gomes-Junior A.R., Benedetti-Rossi G.
<Astron. Astrophys. 584, A96 (2015)>
=2015A&A...584A..96D 2015A&A...584A..96D (SIMBAD/NED BibCode)
ADC_Keywords: Minor planets ; Ephemerides ; Positional data
Keywords: astrometry - celestial mechanics - occultations -
Kuiper belt: general - methods: numerical
Abstract:
The prediction of stellar occultations by trans-Neptunian objects
(TNOs) and Centaurs is a difficult challenge that requires accuracy
both in the occulted star position and in the object ephemeris. Until
now, the most used method of prediction, involving dozens of
TNOs/Centaurs, has been to consider a constant offset for the right
ascension and for the declination with respect to a reference
ephemeris, usually the latest public version. This offset is
determined as the difference between the most recent observations of
the TNO/Centaur and the reference ephemeris. This method can be
successfully applied when the offset remains constant with time, i.e.
when the orbit is stable enough. In this case, the prediction even
holds for occultations that occur several days after the last
observations.
This paper presents an alternative method of prediction, based on a
new accurate orbit determination procedure, which uses all the
available positions of the TNO from the Minor Planet Center database,
as well as sets of new astrometric positions from unpublished
observations.
Orbits were determined through a numerical integration procedure
called NIMA, in which we developed a specific weighting scheme that
considers the individual precision of the observation, the number of
observations performed during one night by the same observatory, and
the presence of systematic errors in the positions.
Description:
The table provides 2895 ground-based observations of 50
trans-Neptunian objects and Centaurs performed between 2007 and 2014.
The table contains the name of the observed TNO, the date of the
observation, the topocentric ICRS coordinates of the object and the
IAU observatory code.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tnoobs.dat 66 2895 Table of ground-based observations of TNOs
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See also:
J/ApJS/189/336 : HST astrometry of TNOs (Benecchi+, 2010)
J/A+A/541/A142 : Prediction of stellar occultations 2008-2015 (Assafin+, 2012)
J/A+A/561/A37 : Prediction of stellar occultations 2012.5-2014 (Camargo+ 2014)
J/A+A/569/A3 : Rotational properties of TNOs (Thirouin+, 2014)
Byte-by-byte Description of file: tnoobs.dat
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Bytes Format Units Label Explanations
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1- 11 A11 --- Name Name or designation of the object
12- 15 I4 yr Obs.Y Year of observation
17- 18 I2 "month" Obs.M Month of observation
19- 28 F10.6 d Obs.D UTC date of observation
29- 45 F17.12 deg RAdeg Topocentric ICRS right ascension
46- 62 F17.12 deg DEdeg Topocentric ICRS declination
63- 66 A4 --- ObsID Observatory code (1)
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Note (1): From Minor Planet Center (code IAU)
http://cfa-www.harvard.edu/iau/lists/ObsCodes.html as follows:
493 = Calar Alto
586 = Pic du Midi
809 = European Southern Observatory, La Silla
874 = Itajuba
J13 = La Palma-Liverpool Telescope
J86 = Sierra Nevada Observatory
W85 = Cerro Tololo-LCOGT A
Z20 = La Palma-MERCATOR
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Acknowledgements:
Josselin Desmars, desmars(at)imcce.fr
(End) Josselin Desmars [IMCCE], Patricia Vannier [CDS] 19-Oct-2015