1. 1 EURONEAR, an international project to study Near Earth Asteroids Ovidiu Vaduvescu Conferinta Diasporei - Workshop Astronomie 22-24 Sep 2010 Bucharest, Romania

2. 2 Why Near Earth Asteroids (NEAs)?  Because this was my proposed subject for my association with IMCCE and Dr. Mirel Birlan;  Because asteroids and Solar System dynamics were the subjects of my Romanian PhD with the regretted Prof. Dr. Arpad Pal of Babes Bolyai Univ, Cluj Napoca (1993-1997);  Because Europe is almost null in NEA survey work, while the Americans own 99.8% of discoveries of the actual NEA population!  Because I liked a lot the movie “Deep Impact” and I really hope to be able to save the world  Because I liked a lot the movie “Deep Impact” and I really hope to be able to save the world

3. 3 MBAs, NEAs, PHAs and VIs  Main Belt Asteroids (MBAs) are minor planets moving between the orbits of Mars and Jupiter, between about 3.1 and 3.5 AU (astronomical units). Since 1800 (the discovery of Ceres), there are more than half million MBAs known today!  Near Earth Asteroids (NEAs) are defined as the asteroids with a perihelion distance (q) less than 1.3 AU. There are more than 7100 NEAs known today.  Potentially Hazardous Asteroids (PHAs) are the NEAs having a Minimum Orbital Intersection Distance (MOID) less than 0.05 AU and the absolute magnitudes (H) less than 22 mag, which corresponds to objects larger than about 150m. There are more than 1100 PHAs known today.  Virtual Impactors (VIs) are the PHAs whose present orbital uncertainty result in a non-zero impact probability with the Earth in the near future. There are about 100 VIs known today, most of them very faint and inaccessible to existing ~1m class surveys.

4. 4 What is EURONEAR? European Near Earth Asteroids Research A project which envisions to establish a coordinated network to follow-up, recover and discover Near Earth Asteroids (NEAs) and Potentially Hazardous Asteroids (PHAs) using two automated dedicated 1-2m telescopes located in both hemispheres and other facilities available to the members of the network. A project which envisions to establish a coordinated network to follow-up, recover and discover Near Earth Asteroids (NEAs) and Potentially Hazardous Asteroids (PHAs) using two automated dedicated 1-2m telescopes located in both hemispheres and other facilities available to the members of the network.

5. 5 The Network / Observing runs  Pic du Midi 1m, France (9n, 2006)  York University 0.6m, Canada (10n, 2002, 2003 & 2004)  OCA Cerro Armazones 0.84m, Chile (3n, 2007)  Las Campanas Swope 1m, Chile (10n, 2008 & 2009)  Cerro Tololo 1m, Chile (5n, 2008)  La Silla ESO 1m, Chile (3n, 2007)  Haute Provence 1.2m, France (11n, 2007, 2010)  INT 2.5m, La Palma (10n, 2009 & 2010)  La Silla ESO/MPG 2.2m, Chile (2n, 2008)  INT 2.5m & ESO/MPG 2.2m (data mining)  CFHTLS 3.6m, Hawaii (data mining)  Subaru 8.3m (data mining, to come soon)!  Vasile Urseanu Observatory 0.3m  Vasile Urseanu Observatory 0.3m Includes mostly 1-2m telescopes accessed via regular observing proposals:

6. 6 Follow up, Recovery and Discovery of NEAs and MBAs Sample of an ESO2m field showing three MBAs and probably one new NEA. The series of frames represents 8 image taken at a small interval (cca 1 min). The search of known and new asteroids and measurement (astrometry and photometry) could be performed by an amateur or student assisted by the Astrometrica program. Alternatively, some automated pipeline could be used.

7. 7 Results: Observations in the Network  224 NEAs, PHAs and VIs followed-up and reported to Minor Planet Centre (MPC) during the last 4 years in about 10 runs using mostly 1-2m class telescopes;  Probably one NEA was discovered in one ESO2m field on 12/13 March 2008, unfortunately being lost due to late inspection.  About 500 known MBAs were observed incidentally in the 2m fields and reported to MPC;  About 500 new MBAs were discovered in the ESO2m, INT 2.5m and Swope 1m observed fields, all being reported to MPC, from which 58 became EURONEAR official discoveries;  We are the first Romanian asteroid discoverers, the team being formed mostly by Romanian students and amateurs;  Part of EURONEAR, two Romanian students were the first to observe in Chile and La Palma.

8. 8 Results: Accurate Astrometry Observed minus calculated (o-c) residuals for EURONEAR NEA observations (left) compared with residuals of the same asteroids observed by all other major surveys. EURONEAR data appear better confined around zero, having a standard statistical error under 0.25” (Birlan, Vaduvescu, Tudorica et al, 2010)

9. 9 Results: Data Mining Besides new observations (subject of time allocation and telescope access), data mining of image archives (scanned photographic plates or CCD) represents another investigation tool of EURONEAR. Given one archive represented by a simple observing log, we look for serendipitous encounters of known NEAs whose positions could be measured and used to ameliorate the orbits. PRECOVERY, a software accessing SKYBOT server at IMCCE facilitates this work. Until now, we studied the following archives:  Bucharest plates 38cm refractor: ~10,000 2x2 deg plates; no apparitions due to low mag limit V~13 (Vaduvescu, Curelaru, Birlan et al, 2009)  CFHT Legacy Survey: ~25,000 Megacam 1x1 deg images, cca 500 encounters (Vaduvescu, Tudorica, Birlan et al, 2010)  ESO/MPG 2.2m WFI (100,000 34’x34’ images) and INT 2.5m (230,000 33’x34’ images): work in progress (in a team of 10 students and amateurs);  Subaru 8.3m SuprimeCam 34’x27’ (next project, collaborators welcomed)

10. 10 Results: Orbital Amelioration Astrometric positions of NEAs (from data mining or new observations) serve to ameliorate of the asteroid orbits (some of them insecure with large errors due to small number of observations or interval). We could classify the results (Vaduvescu et al, 2010):  Extended arcs at first opposition (Precoveries = serenditipitous observations at one opposition before discovery date – from data mining only);  Extended arcs at last opposition (Recoveries at one new opposition – from data mining or new observations);  Refined arcs at one intercalated oppositions (Recoveries – from data mining);  Refined very small arcs (a few weeks);  Extended arcs at second opposition (major recoveries).

11. 11 Results: Photometry of NEAs Long time photometry – a few hrs in successive nights, eventually from multiple coordinated stations. Some physical parameters could be derived from photometry:  Determination of asteroid rotation periods (with accuracy of ~0.001 hr)  Discovery of binary systems (yes, many asteroids are double systems)! This method require dedicated time (a few successive nights and good weather) and relatively large telescope (preferably 2m) to achieve good precision (~0.01mag) Birlan, Vaduvescu, Galad et al, 2010

12. 12 My Dream: 1-2 Dedicated Facilities Motto: “With only one flower, one can not make the spring”   Feb 2008: Five institutional members (IMCCE France, Armagh Observatory UK, Turku Observatory Finland, AICR the Czech Republic, and IA UCN Chile) sent an FP7 application to support EURONEAR for 4 years by the EU. The proposal passed the threshold (with a score 10/15) but could not be financed due to insufficient funding;  Sep 2010: A new FP7 proposal is intended to be submitted at the end of 2010 on behalf of 15 institutions from 10 EU countries actually constituting our EURONEAR Consortium. Presently, we are aiming to submit a 10-20 ME proposal to buy a new 2.3m telescope to be installed in Canary to devote to EURONEAR. An additional 1m telescope, preferably in the South is also envisioned to serve the original aims of our project.

13. 13 Collaborators  EURONEAR Team: M. Birlan, P. Rocher, J. Berthier, F. Colas, V. Lainey (IMCCE Paris), P. Pravec & A. Galad (Ondrejov), D. Asher (Armagh, UK), R. Rekola (Turku, Finland), etc;  About 15 amateurs and students from Romania: A. Tudorica, A. Sonka, R. Toma, M. Badea, T. Badescu, M. Popescu, I. Comsa, L. Curelaru, M. Constantinescu, D. Vidican. C. Opriseanu, C. Vancea, D. Dumitru, A. Paraschiv, D. Lacatus (SARM, Bucharest Astroclub, Univ. of Bucharest, Cluj Napoca), etc;  Former students and colleagues from Chile: F. Pozo, A. Barr, P. Longa, J. P. Colque, Prof. E. Unda-Sanzana, etc;  Present colleagues and students from Spain: J. Skvarc & T. Agocs (ING), J. Licandro (IAC Tenerife), J. L. Ortiz & R. Duffard (IAA Granada), etc;  Others welcomed!

14. 14 References Vaduvescu et al, 2006-2010: About 40 Minor Planet Circulars (see MPC or ADS) Vaduvescu, O., 2006, RoAJ 15, 171 & 14, 199 "Observing Near Earth Asteroids with a Small Telescope" Vaduvescu, O. et al., 2008, Pl. Sp. S. 56, 1913 "EURONEAR: First Results" Vaduvescu, O. et al., 2009, Astron. Nachr. 330, 7, 698 "EURONEAR: Data mining of asteroids and Near Earth Asteroids" Birlan, M., Vaduvescu, O., et al., 2010, A&A 511, A40 "More than 160 near Earth asteroids observed in the EURONEAR network" Vaduvescu, O., et al. 2010, submitted to AN (June 2010) "Mining the CFHT Legacy Survey for known Near Earth Asteroids" Pravec, P., et al., 2010, Nature 466, 1085 "Asteroid pairs formed by rotational fission" http://www.ovidiuv.ca/papers/