Ground-based astrometry calibrated by Gaia DR1

• Verfasst von: Spoto, Federica [VerfasserIn]
• Verfasst von: Altmann, Martin [VerfasserIn]
• Titel: Ground-based astrometry calibrated by Gaia DR1
• Titelzusatz: new perspectives in asteroid orbit determination
• Verf.angabe: F. Spoto, P. Tanga, S. Bouquillon, J. Desmars, D. Hestroffer, F. Mignard, M. Altmann, D. Herald, J. Marchant, C. Barache, T. Carlucci, T. Lister, and F. Taris
• E-Jahr: 2017
• Jahr: 31 October 2017
• Umfang: 8 S.
• Fussnoten: Gesehen am 13.01.2021
• Titel Quelle: Enthalten in: Astronomy and astrophysics
• Ort Quelle: Les Ulis : EDP Sciences, 1969
• Jahr Quelle: 2017
• Band/Heft Quelle: 607(2017) Artikel-Nummer A21, 8 Seiten
• ISSN Quelle: 1432-0746
• DOI: doi:10.1051/0004-6361/201731439
• Datenträger: Online-Ressource
• Sprache: eng
• K10plus-PPN: 1571412034

Abstract

Data Release 1 (GDR1) is a first, important step on the path of evolution of astrometric accuracy towards a much improved situation. Although asteroids are not present in GDR1, this intermediate release already impacts asteroid astrometry.<i>Aims. <i/>Our goal is to investigate how the GDR1 can change the approach to a few typical problems, including the determination of orbits from short-arc astrometry, the exploitation of stellar occultations, and the impact risk assessment.<i>Methods. <i/>We employ optimised asteroid orbit determination tools, and study the resulting orbit accuracy and post-fit residuals. For this goal, we use selected ground-based asteroid astrometry, and occultation events observed in the past. All measurements are calibrated by using GDR1 stars.<i>Results. <i/>We show that, by adopting GDR1, very short measurement arcs can already provide interesting orbital solutions, capable of correctly identifying near-Earth asteroids (NEAs) and providing a much more accurate risk rating. We also demonstrate that occultations, previously used to derive asteroid size and shapes, now reach a new level of accuracy at which they can be fruitfully used to obtain astrometry at the level of accuracy of <i>Gaia <i/>star positions.