New asteroid models Virtual Observatory Resource

Authors
  1. Durech J.
  2. Hanus J.
  3. Published by
    CDS
Abstract

In addition to stellar data, Gaia Data Release 2 (DR2) also contains accurate astrometry and photometry of about 14000 asteroids covering 22 months of observations. We used Gaia asteroid photometry to reconstruct rotation periods, spin axis directions, and the coarse shapes of a subset of asteroids with enough observations. One of our aims was to test the reliability of the models with respect to the number of data points and to check the consistency of these models with independent data. Another aim was to produce new asteroid models to enlarge the sample of asteroids with known spin and shape. We used the lightcurve inversion method to scan the period and pole parameter space to create final shape models that best reproduce the observed data. To search for the sidereal rotation period, we also used a simpler model of a geometrically scattering triaxial ellipsoid. By processing about 5400 asteroids with at least ten observations in DR2, we derived models for 173 asteroids, 129 of which are new. Models of the remaining asteroids were already known from the inversion of independent data, and we used them for verification and error estimation. We also compared the formally best rotation periods based on Gaia data with those derived from dense lightcurves. We show that a correct rotation period can be determined even when the number of observations N is less than 20, but the rate of false solutions is high. For N>30, the solution of the inverse problem is often successful and the parameters are likely to be correct in most cases. These results are very promising because the final Gaia catalogue should contain photometry for hundreds of thousands of asteroids, typically with several tens of data points per object, which should be sufficient for reliable spin reconstruction.

Keywords
  1. solar-system
  2. asteroids
Bibliographic source Bibcode
2018A&A...620A..91D
See also HTML
https://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/620/A91
IVOA Identifier IVOID
ivo://CDS.VizieR/J/A+A/620/A91
Document Object Identifer DOI
doi:10.26093/cds/vizier.36200091

Access

Web browser access HTML
http://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/620/A91
https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/620/A91
http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/620/A91
IVOA Table Access TAP
http://tapvizier.cds.unistra.fr/TAPVizieR/tap
Run SQL-like queries with TAP-enabled clients (e.g., TOPCAT).

History

2018-11-30T09:00:35Z
Resource record created
2018-11-30T09:00:35Z
Created
2019-01-07T09:13:33Z
Updated

Contact

Name
CDS support team
Postal Address
CDS, Observatoire de Strasbourg, 11 rue de l'Universite, F-67000 Strasbourg, France
E-Mail
cds-question@unistra.fr