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Japanese Discover Large Earth-Crossing Asteroid

Armagh Observatory, 31st October 2000.

A team of Japanese scientists including Armagh astronomer Dr David Asher have announced the discovery of the second largest known Earth-crossing asteroid. The group is based at the new Japanese Spaceguard Centre at Bisei, west of Osaka. The brightness of the new object suggests that it is between five and ten kilometres in diameter, about the same size as the comet or asteroid that caused the extinction of the dinosaurs 65 million years ago.

The cosmic cannonball was first observed on October 21st from the Japanese Spaceguard Centre. The subsequent tracking and orbit determination was assisted by Armagh asteroid expert David Asher, who is currently visiting Japan to help in the setting up of the new Spaceguard Centre funded by the Japanese government. He counts himself lucky to be involved in such an important find, saying "I just had to turn up and do nothing, and within three days this discovery. Quite a skill!"

Remarkably, the new asteroid was discovered with a test telescope, a tiny instrument having an aperture just ten inches across, a size of telescope owned by quite a few amateur astronomers. The discovery suggests that there must be many more kilometre and sub-kilometre size asteroids to be found.

The new asteroid, which has been given the designation 2000 UV13, and knowledge of whose orbit is continually being refined as new data come in, moves on a path that brings it within about ten million kilometres of the Earth's orbit, or about thirty times the distance to the Moon. On the cosmic scale this is remarkably close, but current observations give no indication that it will collide with our planet in the foreseeable future.

On 18 September the Minister of Science, Lord Sainsbury, published a Task Force report on the hazard posed by Near Earth Objects. The report confirms the high level of risk posed by comet or asteroid impacts, and makes recommendations for government action, notably that the UK together with international partners should build a new 3-metre class search telescope to complement existing US and Japanese programmes; and that the UK should set up a Centre for Near Earth Objects to promote and coordinate work on the subject in this country.

Asteroid search telescopes are quite different from conventional astronomical instruments, and present various technological challenges. Engineers at Telescope Technologies Limited, a company based in Liverpool, are working on possible designs after discussions last week with UK asteroid and comet experts.

For further details, contact John McFarland or Mark Bailey at Armagh Observatory, College Hill, Armagh, BT61 9DG; Tel: 028-3752-2928, FAX: 028-3752-7174; e-mail: jmf@star.arm.ac.uk, and meb@star.arm.ac.uk.

Photographs of the Japan SpaceGuard Observatory at Bisei are available at: http://neowg.mtk.nao.ac.jp/neo/photo/
A list of potentially-hazardous asteroids is given at: http://cfa-www.harvard.edu/iau/lists/Dangerous.html

See also:
NEO Impact Hazard
Today's Map of the Inner Solar System

Last Revised: 31st October 2000
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