The Lowell Observatory Near-Earth-Object Search (LONEOS) is an ongoing search for asteroids and comets that can approach our planet. These bodies, collectively called near-Earth objects (NEOs), have bombarded Earth throughout history, sometimes with devastating consequences. A mass extinction of more than half the species on Earth, including the dinosaurs, about 65 million years ago was likely precipitated by the impact of a 15 kilometer (km) asteroid or comet in the Yucatan peninsula.

There are thought to be roughly 1,000 near-Earth asteroids (NEAs) larger than 1 km. As of 2003 July, about 655 have been found. One kilometer is considered the threshold size for an asteroid that would have globally catastrophic consequences if it hit Earth. Finding these large asteroids is the first step towards averting future catastrophic impacts. That task requires a network of telescopes searching the night sky for these potentially hazardous objects. LONEOS is part of that effort.

LONEOS has the capability to scan the entire sky accessible from Flagstaff, Arizona, every month. The telescope is able to record objects to a magnitude limit near V=19.3 or about 100,000 times fainter than can be seen with the naked eye. As of 2004 July, LONEOS had submitted more than 2.8 million asteroid observations to the IAU Minor Planet Center. After 10 years of full-time operation, we estimate that LONEOS could discover 500 of the 1-km or larger NEOs and perhaps twice as many smaller ones, thus substantially increasing our knowledge of these bodies.

Discovery Summary

As of 2004 Jul 23

Asteroid Type Discoveries
Aten 17
Apollo 97
Amor 82
Comets 16
Total 213

Discoveries: The full list of LONEOS NEA and comet discoveries.

Staff: Meet the LONEOS science staff.

Milestones: A summary of significant achievements for LONEOS.


Last updated 2004 Jul 23

Contact: Bruce Koehn (koehn@lowell.edu)
Web Curators: Ted Bowell and Bruce Koehn

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