The CINEOS Project

Campo Imperatore Near-Earth Objects Survey

Telescope Begin End
Schmidt Aug 2001 Dec 2002

INTRODUCTION
The Campo Imperatore Near Earth Object Survey (CINEOS) is a dedicated search and follow-up program of Near-Earth Objects, with special emphasis to the study of objects located at small solar elongations. It is carried out at the Campo Imperatore station of the Rome Observatory near the summit of the Gran Sasso Mountain, at about 2,150 meters of elevation. The station is located about 130 km north-east of Rome. Longitude and latitude are respectively 13.5581 deg East and 42.4442 North.

CINEOS was born in 1996 from a collaboration between the Observatory of Rome (OAR-INAF), and the Istituto di Astrofisica Spaziale (IASF-CNR) within the ITANET project.
After a long hiatus from mid-1997, CINEOS has recently restarted operations taking advantage of improved hardware and software capabilities. The Observatory of Torino has been also involved in this project since the restart of the project. Operated at the Schmidt telescope (60-90-183 cm) available at the station, the program uses between 10 and 14 nights per month, usually around the first and last quarter of the moon.

INSTRUMENTATION
Schmidt Telescope The CINEOS project restarted operations in the late summer of 2001 and exploited the potential of the 1996/97 epoch through an improved software and hardware settings. Today, CINEOS observations are performed using the Schmidt telescope (60/90/183 cm) of the Campo Imperatore Observatory and its new focal plane array, the ROSI CCD camera.

ROSI is equipped with a 2048 x 2048, 13,5 micron per pixel, high efficiency, thinned back illuminated CCD chip produced by Marconi Ltd. (formerly known as EEV). The sampling is 1.51 arcsec/pixel and it corresponds to a field of view (FoV) of 52' x 52'. The camera is also equipped with a standard Johnson filter set (U, B, V, R and I) mounted on an automatic jukebox system. The high quantum efficiency (nearly 90 % at the peak) and the extremely low dark current guaranteed by the liquid nitrogen cooling system (working temperature is -100 C deg), coupled with the fast (f/3) Schmidt optics makes this system extremely valuable on moving objects where high photometric speed is required.

The telescope mechanics have also been recently upgraded with new encoders, motors and control system. Thanks to the quality of these devices the telescope is now able to perform open loop tracking (without any guider) for periods of many minutes and no visible star stretching.

SOFTWARE
To support fast data processing an automated reduction pipeline is also working. It uses the PREPROCESS software to perform flat-fielding, bad pixel and fringing pattern removal.

Another reduction pipeline is also under improvement/preparation: it performs automatic detection of moving objects, automatic astrometric reduction and semi-automatic recognition of unusual objects to be flagged for the Minor Planet Center as possible candidate for the NEO Confirmation Page. At this preliminary stage of the activity, part of the work is currently carried out with the Astrometrica software package and the USNO A2.0 astrometric catalog.
Further information about self-made software will be posted on this page very soon.

As for orbit and ephemeris calculation we use several databases: self-made software (mostly by Giuseppe Forti of the Arcetri Astrophysical Observatory), the NEODyS database and the Orbfit software for the preparation of the observing program. We also make full use of several features of the Minor Planet Center and the Lowell database. The choice of targets for NEO follow-up purposes mostly depends on the suggestions provided by the Spaceguard Central Node.

HARDWARE
From the computing point of view the project is based on the following resources: working on the Campo Imperatore LAN. Data is currently stored on CD-ROMs.

SCIENTIFIC BACKGROUND AND GOALS
The science of CINEOS consists of two main observing activities: 1) To search for Near-Earth Objects, concentrating activities at small solar elongations. Our objective is to optimize a ground-based system towards the discoveries of: Although the NEO discovery rate has grown significantly over the last four years, our knowledge of bodies with small semi-major axis remains largely incomplete (Atens) or totally incomplete (IEOs). In fact most search programs concentrate their efforts near the opposition region where it is difficult if not impossible to find these objects.
Atens are also very important because numerical simulations have shown that they have the highest frequency of close encounters with the Earth. Sometimes Atens can evolve into orbits completely inside that of the Earth and vice versa. Thus, there are bodies that can come very close to the Earth, but are very difficult to observe from the ground.

2) The second goal of CINEOS is to provide rapid astrometric data for:

For obvious reasons, the survey activity will be carried out mostly at the beginning and near the end of the night, while part of the middle of night time is usually available for the follow-up work. As a targeted follow-up system, CINEOS takes advantage of the combination of the relatively faint limiting magnitude and large FoV (probably the largest in the world for this activity). Follow-up can be provided up to magnitude 21, occasionally to 22 on the best nights.
Coordination of the follow-up work will be accomplished within the Spaceguard Central Node facilities. An essential side of the work is to chose targets that cannot be done elsewhere very easily during the epoch of the observing run.

OBSERVATIONAL STRATEGY
We performed some numerical silmulations in order to obtain the most effective observational strategy, through two independent studies.

In the first study we integrated a population of 1382 Atens and 524 IEOs with absolute magnitude H < 22, kindly provided by A. Morbidelli, in order to evaluate the density distribution of these objects at different elongations. A second study includes another sample of 360 IEOs obtained integrating the orbits of 565 real Near Earth Asteroids (NEAs) for 5 Mys. These populations are fictitious but realistic, because they considered among the best dynamical models and integration techniqes available at present. In our calculations we took into account the trailing loss effect and the technical characteristic of the CINEOS Schmidt telescope.

Our results suggest that the best performing strategy, as described better in the next section, is to take exposures of 60 - 120 seconds in order to reach an effective limiting magnitude of 20.0 - 20.5 V for moving objects under good conditions. This is also a good compromise between limiting magnitude and trailing losses. Sky coverage is performed starting from solar elongations of 40 degrees.

Although the object detection is done semi-automatically, when time allows, we try to repeat the blinking process visually by eye in order to minimize the risk of missing detections. We give precedence to the fields at small solar elongations. It should not surprise that the two most interesting discoveries so far, 2002 LC58 and 2002 MQ were detected by the observer and not by the software, which is going to get improved in the near future.

For the time in which we are about to submit the astrometric data to the Minor Planet Center, we use self-made software in order to help the MPC in discriminating interesting objects from typical main belt motion rates so that interesting targets could be posted on the NEOCP.

RESULTS
Even though CINEOS restarted operations in August 2001, only since June 2002 the observing activity has been carried out at a more satisfactory level. So far, the best results were achieved in June with the discovery of two unusual objects, 2002 LC58 and 2002 MQ, both initially posted on the NEO Confirmation Page.

2002 LC58 was particularly interesting because it was discovered at 60 degrees of solar elongation, in the morning sky. Despite its unusual motion, it was impossible to discriminate the real nature of its orbit until the observing arc became of 25 days. 2002 MQ, on the other hand, was discovered while following 2002 MN, a very interesting NEA.

The 3rd September 2002 CINEOS discovered its first NEO (2002RQ25): an Apollo object with an estimated size of about 200-300 meters. On November 27th 2002 another NEO (2002WP11) of the Amor family has been discovered by CINEOS.  

October-November 2002 results, for a total of 3576 published positions:  

Known New PHA
NEO Amor
2
0
0
Apollo
7
0
3
Aten
1
0
1
Total
10
0
4
MBO
700
173
Unusual
0
0
Centaurus and
Scattered-Disk
0
0
Total
700
173
 

Activity results since August 1st 2001, 11640 published positions:  

Known New PHA
NEO Amor
11
0
2
Apollo
20
1
6
Aten
8
0
2
Total
39
1
10
MBO
2274
469
Unusual
0
2
Centaurus and
Scattered-Disk
0
0
Total
2313
472
 

Published positions plot since August 2001:

Discoveries plot since August 2001:

STAFF
CINEOS scientific staff consists of the following people, some directly involved in the observations, others simply concentrating on dynamical studies and/or for software development:

LINKS

REFERENCES
  • Boattini A., Carusi A: Atens: Importance among NEAs and Search Strategies, Vistas in Astronomy, Vol. 41, No. 4, PP 527-541, 1997.
  • Bottke W.F., Morbidelli A. et al.: Debiased Orbital and Absolute Magnitude Distribution of the Near-Earth Objects, Icarus V.156, Issue 2, 399-433,2002.
  • Bowell E., Muinonen K., p.149. Hazards due to comets and asteroids, Space Science Series, Tucson,AZ: Edited by Tom Gehrels, M. S. Matthews. and A. Schumann.Published by University of Arizona Press, 1994.
  • D'Abramo G., Harris A. W. (JPL), Boattini A., Werner S.C.,Harris A. W. (DLR), Valsecchi G.B.: A simple probabilistic model to estimate the population of Near Earth Asteroid.Icarus153 214-217,2001.
  • Di Paola A.:PREPROCESS: a fast image processing tool Gamma-Ray Bursts in the Afterglow Era 17-20 Roma, Italy, 390-392, October 2000.
  • Masi G.: Searching for Inner-Earth Objects: a possible ground-based approach. In preparation, 2002.
  • Morrison D.:The Spaceguard Survey: Report of the NASA, International Near-Earth-Object Detection Workshop. NASA publication,1992.
  • MPEC 2002-M14: 2002 MN, 2002 June 18, 21:58 UT. Minor Planet Center, Smithsonian Astrophysical Observatory, Cambridge, MA, U.S.A.
  • Pedichini F., D'Alessio F, Di Paola A. et al. ROSI: a compact 2k x 2k CCD imager for Schmidt telescopes.SPIE 2000 4008 389-396.
  • Rabinowitz D. L. et al. :A reduced estimate of the number of kilometre-sized near-Earth asteroids. Nature 43 165-166, 2000.
  • Speziali R., Pedichini F. Design of a new cryostat for the Schmidt Telescope at Campo Imperatore Rome Astronomical Observatory. Internal Report #2, May 1997