Lowell Observatory Near-Earth-Object Search
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Lowell Observatory Near-Earth-Object Search (LONEOS) is a program run by NASA and Lowell Observatory in Flagstaff, Arizona, to discover near-Earth objects. The LONEOS system began in 1993. The principal investigator is Ted Bowell.
LONEOS is a system designed to find Earth-crossing asteroids (ECAs) and comets (ECCs), collectively known as near-Earth objects (NEOs). These objects can occasionally collide with Earth sometimes with devastating consequences. Finding large NEOs is the first step in averting a collision. It is thought that there are about 1600 ECAs larger than 1 km in diameter. However, only 100 ECAs are known presently. Thankfully, in 1999-2000, the efficiency of the LONEOS program in discovering NEOs has increased significantly due to the upgrades to the CCD camera and data reduction software.
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[edit] Telescope
LONEOS uses a 0.6-meter f/1.8 Schmidt telescope, which was acquired from Ohio Weslayan University in 1990, and a 16 megapixel CCD detector that gives a wide field of view of 3.17 by 1.58 degrees of the sky. It has a nightly scan rate of about 1,000 square degrees. (The camera can cover the entire visible sky in about a month.) The CCD has detected asteroids as faint as visual magnitude 19.8.
[edit] CCD camera
The CCD chip is made by Loral, with two butted chips in the camera. The chip size is 2048 by 2048 pixels. It also has thermoelectric cooling to -50 degrees Celsius. The camera itself is cylindrical, 7 inches in diameter. The readout rate is 250 kpixels/sec. It has 14 bit pixels, and has 50 percent detection in all three scans at 19.6 magnitude. The field of view is 3.17 degrees by 1.58 degrees. The readout time is 34 seconds, and the pixel size is 15 micrometers. This has 40 percent maximum quantum efficiency, and was built by Chris Stubbs, Alan Diercks, and John Angione of the University of Washington, Seattle. As of April 26, 1995, the camera is complete except for the field flattener. The field flattener will be installed as soon as it arrives, and the camera will be received shortly.
[edit] Camera management
The task of managing the camera and searching for asteroids is primarily performed using computers and some custom-written software.
[edit] Computers
It runs on 6 R3000 processors, has 64 MB of main memory, 2 GB of disk storage, has an aggregate speed of ~160 MIPS, has VME camera interface, and Silicon Graphics IRIS 4D/220GTX.
[edit] Software
The computer runs on UNIX. The software was developed using FORTRAN 77. The FORTRAN extensions (PFA) allow simultaneous use of all processors.
[edit] Observing site
The astronomers of Lowell Observatory perform most of their observations through the telescopes on Anderson Mesa. The 1961 addition of the Perkins 69 inch (soon to be 72 inch), it became clear that a site was needed that would be more immune to the growing light pollution of Flagstaff. Anderson Mesa was a logical choice for several reasons. It is in the Coconino Natural Forest so it cannot be developed, it is on the south edge of the Colorado Plateau at an altitude of 2200 m., and it is easily accessible through good roads from Flagstaff.
[edit] The LONEOS dome
In 1970, funds from the Lowell endowment were used to construct a 24 foot diameter dome on Anderson Mesa. This dome housed the A. Lawrence Lowell Astrograph, the 13 inch camera used to discover Pluto. This was moved to Anderson Mesa due to the bright lights of the city of Flagstaff. However, as of 1993, the astrograph has been moved back to Mars Hill because the dome is undergoing renovations to accept the LONEOS telescope.
[edit] Press releases
[edit] May 20, 2004
LONEOS Discoveres Asteroid with the Smallest Orbit MPC Electronic Circular Announcement Orbit Diagram(PDF)
[edit] October 15, 2003
Recovery of 1937 UB (Hermes) Recovery images of 1937 UB (Hermes) Orbit Diagram Documentation of Hermes' Recovery
[edit] October 3, 2003
Discovery of the closest Earth-approaching asteroid 2003 SQ222 Discovery images of 2003 SQ222 Orbit Diagram
[edit] August 14, 2001
Discovery of large Earth-Crossing Damocloid Discovery images Orbit Diagram
[edit] LONEOS scientific staff
Lowell staff: Dr. Ted Bowell, Principal investigator Dr. Bruce Koehn, Computer programming.
External staff: Dr. Steve Howell, Department of Physics and Astronomy, CCD performance modeling Dr. Karri Muinonen, University of Helsinki, Asteroid detection modeling
[edit] See also
- NASA's Planetary Data System (PDS) [1]
- Minor Planet Center
- Spacewatch Project
