William Atkins
Wednesday, 18 February 2009 21:30
Science -
Space
Page 1 of 3
Andrea Milani and his team of professional asteroid hunters have upgraded the probability that Asteroid 1999 RQ36 could hit the Earth between the years 2169 and 2199.
The asteroid, also called (101955) 1999 RQ
36, is classified as an
Apollo asteroid, with a diameter estimated to be about 580 meters (1,900 feet) and
an approximated mass of 1.4 x 10
11 kilograms (3.1 x 10
11 pounds)
Apollo asteroids are a group of near-Earth asteroids that are named after Asteroid 1862 Apollo, the first asteroid discovered in the group. It was discovered by Karl Wilhelm Reinmuth.
The American Astronomical Society paper “
The Shape and Spin of 101955
(1999 RQ36) from Arecibo and Goldstone Radar Imaging” states,
“Radar
images at 19-m and 15-m resolution in 1999 and 7.5-m resolution in 2005
show that RQ36 is well approximated as an irregular spheroid about 580m
in diameter. There is no evidence in the radar images for a satellite
larger than 15m. The nearly spheroidal shape suggests that it is a
strengthless rubble pile, and may have formed by mechanisms similar to
near-Earth binary systems, and may even have been in a binary system in
its past.”
Further information on the asteroid is found on the website “
101055 1999 RQ36” of the NASA Near Earth Object Program.
The NASA website states that there are eight (8) potential future
impact dates by the asteroid, according to radar, Doppler, and optical
observations made between 1999 and 2006 of the asteroid. They occur in
2169, (two in) 2182, 2185, 2189, 2192, 2195, and 2199.
The asteroid was discovered in 1999 by Lincoln Near-Earth Asteroid
Research (
LINEAR), and have been tracked over the years by the Arecibo
Observatory Planetary Radar and the Goldstone Deep Space Network.
Page two continues with tracking by the LINEAR project, along with more news on the near-Earth asteroid 1999 RQ
36.
