739 observed NEAs and new 2-4m survey statistics within the EURONEAR network

Ovidiu Vaduvescu (1, 2, 3) , Mirel Birlan (1) , Alex Tudorica (4, 5) , Marcel Popescu (1, 6, 7) , François Colas (1) , David J. Asher (8) , Adrian Sonka (7, 9) , Oana Suciu (10, 11) , Daniela Adriana Lacatus (12, 13, 14) , Alin Razvan Paraschiv (12, 13, 14) , Toma Badescu (5) , Ovidiu Tercu (14, 15) , Alex Dumitriu (14, 15) , Aurel Chirila (14, 15) , Bringfried Stecklum (16) , Javier Licandro (3, 12) , Alin Nedelcu (1, 6) , Emil Turcu (17) , Frédéric Vachier (1) , Laurène Beauvalet (1) , François Taris (1) , Sébastien Bouquillon (1) , Francisco Pozo Nuñez (18) , Juan Pablo Colque Saavedra (19) , Eduardo Unda-Sanzana (18) , Mansour Karami (20, 21, 22) , Habib G. Khosroshahi (21) , R. Toma (8, 11) , Hugo Ledo (2, 23) , Amy Tyndall (2, 24) , L. Patrick (2, 25) , Dora Fohring (2, 26) , David Muelheims (5) , Georg Enzian (5) , Dominik Klaes (5) , Daniel Lenz (5) , Peter Mahlberg (5) , Y. Ordenes (5) , K. Sendlinger (5)

1 IMCCE - Institut de Mécanique Céleste et de Calcul des Ephémérides
2 ING - Isaac Newton Group of Telescopes
3 IAC - Instituto de Astrofisica de Canarias
4 BCGS - Bonn-Cologne Graduate School of Physics and Astronomy
5 AlfA - Argelander-Institut für Astronomie
6 Astronomical Institute of Romanian Academy
7 Bucharest Astroclub
8 Armagh Observatory [Armagh]
9 Astronomical Observatory ”Admiral Vasile Urseanu”
10 Faculty of Mathematics and Informatics
11 SARM - The Romanian Society for Meteors and Astronomy
12 Research Center for Atomic Physics and Astrophysics, Faculty of Physics
13 Institute of Geodynamics "Sabba S. Stefanescu"
14 Calin Popovici Astronomy Club
15 Galati Astronomical Observatory
16 TLS - Thüringer Landessternwarte Tautenburg
17 Astronomical Observatory of "Stefan cel Mare"
18 Instituto de Astronomıa
19 Unidad de Astronomia
20 Isaac Newton Group of Telescopes
21 School of Astronomy
22 Department of Physics [Tehran]
23 Centre for Astrophysics Research
24 JBCA - Jodrell Bank Centre for Astrophysics
25 Department of Physics and Astronomy [Sheffield]
26 Department of Physics, Centre for Advanced Instrumentation

We report follow-up observations of 477 program Near-Earth Asteroids (NEAs) using nine telescopes of the EURONEAR network having apertures between 0.3 and 4.2 m. Adding these NEAs to our previous results we now count 739 program NEAs followed-up by the EURONEAR network since 2006. The targets were selected using EURONEAR planning tools focusing on high priority objects. Analyzing the resulting orbital improvements suggests astrometric follow-up is most important days to weeks after discovery, with recovery at a new opposition also valuable. Additionally we observed 40 survey fields spanning three nights covering 11 sq. degrees near opposition, using the Wide Field Camera on the 2.5m Isaac Newton Telescope (INT), resulting in 104 discovered main belt asteroids (MBAs) and another 626 unknown one-night objects. These fields, plus program NEA fields from the INT and from the wide field MOSAIC II camera on the Blanco 4m telescope, generated around 12,000 observations of 2,000 minor planets (mostly MBAs) observed in 34 square degrees. We identify Near Earth Object (NEO) candidates among the unknown (single night) objects using three selection criteria. Testing these criteria on the (known) program NEAs shows the best selection methods are our epsilon-miu model which checks solar elongation and sky motion and the MPC's NEO rating tool. Our new data show that on average 0.5 NEO candidates per square degree should be observable in a 2m-class survey (in agreement with past results), while an average of 2.7 NEO candidates per square degree should be observable in a 4m-class survey (although our Blanco statistics were affected by clouds). At opposition just over 100 MBAs (1.6 unknown to every 1 known) per square degree are detectable to R=22 in a 2m survey based on the INT data, while our two best ecliptic Blanco fields away from opposition lead to 135 MBAs (2 unknown to every 1 known) to R=23.

Mots clés: minor planets; near Earth asteroids; main belt asteroids; a strometry and orbits; follow-up and discovery; survey statistics

Domaines: Planétologie et astrophysique de la terre [astro-ph.EP]; Planétologie et astrophysique de la terre [astro-ph.EP]

Ovidiu Vaduvescu, Mirel Birlan, Alex Tudorica, Marcel Popescu, François Colas, et al.. 739 observed NEAs and new 2-4m survey statistics within the EURONEAR network. 2013. ⟨hal-00855023⟩