More than 160 Near Earth Asteroids observed in the EURONEAR network

Mirel Birlan (1) , O. Vaduvescu (1, 2, 3) , A. Tudorica (4, 5) , A. Sonka (6) , A. Nedelcu (1, 7) , A. Galad (8) , Florent Colas (1) , F. Pozo N. (3) , A. Barr D. (3) , R. Toma (4) , I. Comsa (9) , P. Rocher (1) , V. Lainey (1) , D. Vidican (10) , D. Asher (11) , C. Opriseanu (10) , C. Vancea (4) , J. P. Colque (3) , C. P. Soto (12) , R. Rekola (13) , E. Unda-Sanzana (3)

1 IMCCE - Institut de Mécanique Céleste et de Calcul des Ephémérides
2 Isaac Newton Group of Telescopes
3 Instituto de Astronomıa
4 Department of Physics
5 ISS - Institute of Space Science [Bucharest-Măgurele]
6 Astronomical Observatory ”Admiral Vasile Urseanu”
7 Astronomical Institute of Romanian Academy
8 ASU / CAS - Astronomical Institute of the Czech Academy of Sciences
9 UBB - Babes-Bolyai University [Cluj-Napoca]
10 Astroclubul Bucures
11 Armagh Observatory [Armagh]
12 Departamento de Ingenierıa de Sistemas y Computacion
13 Tuorla Observatory

Astrometry is mandatory in order to acquire the positional information necessary to define and improve orbits of NEAs and PHAs and to study their trajectories through the solar system, especially in the vicinity of Earth. Photometry is required to derive some physical information about NEAs and PHAs. In order to achieve these objectives, the main method of research of the EURONEAR is the follow-up programme of objects selected by a few criteria, carried out mostly at 1m-class telescopes endowed with medium and large field cameras. 162 NEAs summing more than 1,500 individual positions were observed for a total time of 55 nights in both visiting mode and regular runs using nine telescopes located in four countries. The observations were reduced promptly and reported to the Minor Planet Centre (MPC) which validated and included them in the MPC and NEODyS databases following the improvement of their orbital elements. For one binary NEA we acquired photometry and were able to determine its orbital and rotational periods. Complementary to the follow-up work, as many as 500 unknown moving objects consistent with new Main Belt asteroids and one possible NEA were discovered in the analyzed fields. Our positions present 1′′ precision with an accuracy of 0.2-0.4′′ , sufficient for achieving our immediate main goals. The observations and data reduction were conducted by our network members, which included some students and amateurs supervised by professional astronomers. In most cases, we increased the observational arcs decreasing the uncertainties in the orbits, while in some cases the new positions allowed us to recover some bodies endangered to be lost, defining their orbits.

Mots clés: astrometry; celestial mechanics; observations; solar system; asteroids

Domaines: Autre

Mirel Birlan, O. Vaduvescu, A. Tudorica, A. Sonka, A. Nedelcu, et al.. More than 160 Near Earth Asteroids observed in the EURONEAR network. 2009. ⟨hal-00441035⟩