As of December 2008, the MPC had a database of 59 million observations of more than 435,000 small bodies, with a second database of more than 10 million observations of objects having no or incomplete orbital information. The MPC receives daily observations of small bodies. The MPC first identifies new observations with known objects or determines that the object is new. All orbits of identified objects are updated and improved daily. Most, but not all, MPC processing is now automated. Observations of NEOs are made available to the public in less than 24 hours after they are acquired; comet observations can require up to a week to process and are largely not automated (Spahr, 2008).

All incoming observations from NEO surveys are checked routinely for potential NEOs. This process is now automated: on the basis of its orbit, any new discovery is assigned a probability code of being an NEO. New possible NEOs are posted on the Web NEO Confirmation Page (NEOCP) in order to facilitate follow-up observations within minutes of posting. Updating of the NEOCP is 95 percent automatic; data and calculated orbits are publicly available.

Recent upgrades to computer equipment allow the MPC to calculate tens of thousands of orbit improvements per day. Access has also been established to a 1,000+ node supercluster run by the Smithsonian Institution, and the MPC is purchasing nodes for this computer. The MPC is currently able to handle the large volumes of data expected in the near future from NEO discovery programs using larger telescopes.

Near Earth Object Program Office

The Near Earth Object Program Office operates at the Jet Propulsion Laboratory (JPL) for NASA; it is charged with coordinating the NEO observations program for NASA. This office is fully funded by NASA and maintains Web-accessible information about NEOs, including their close approaches to Earth as well as NEO discovery statistics.

The NEO Program Office also maintains the automated Sentry software, a collision-monitoring system that continually scans the most current asteroid orbit data for objects that could hit Earth in the next 100 years. When a potential impactor is detected, its future orbit is calculated along with its uncertainty, and the results are published in the Sentry Risk Table on the NEO Program Office Web site.

Near-Earth-Objects Dynamic Site

The NEODyS maintains Web-accessible information about NEOs including orbits, an information database sorted by individual NEOs, and risk assessment of possible impact. The NEODyS is maintained at the University of Pisa, Italy, with a mirror image site at the University of Valladolid, Spain, to ensure that information is always accessible to users.

PAST NEAR-EARTH-OBJECT DISCOVERY EFFORTS

The survey and discovery effort for NEOs has advanced through several phases. Significant initial progress in the effort to identify the NEO population benefited greatly from the seminal efforts at many different telescope systems. The size of NEOs that can be detected is, however, related to the sizes of telescopes and their optics, cameras, and detection software, as well as to the observing strategy of the teams performing the searches. In recent years, some previous NEO survey programs have ended or are being phased out of operation because surveys more capable of finding smaller-diameter NEOs have become operational, and the emphasis on detection has shifted to objects with increasingly smaller diameters. These previous surveys, the Lowell Observatory Near-Earth-Object Search (LONEOS) and the Near-Earth Asteroid Tracking (NEAT) Program, are described below.

Lowell Observatory Near-Earth-Object Search

The LONEOS, operated by the Lowell Observatory, had the capability to scan the entire sky accessible from Flagstaff, Arizona, every month. The 0.6-meter-diameter telescope could record objects about 100,000 times



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