Asteroid Toutatis Arriving 29th Sept... Jul 29, 2004 1:10:45 GMT -6
Post by Chicago Astronomer Joe on Jul 29, 2004 1:10:45 GMT -6
Asteroid 4179 - Toutatis
Toutatis, a potato shaped asteroid, will be making a close approach to Earth on September 29th 2004, and will pass within 4 lunar distances of Earth - (0.0104 A.U.), presenting a good opportunity for observation. This will be the closest approach of any known asteroid or comet between now and 2060. Toutatis , an Alinda asteroid, has dimensions of 2.9 miles by 1.5 miles by 1.2 miles.
(The Alinda asteroids are a group of asteroids with a mean orbital radius of 2.5 AU and an orbital eccentricity approximately between .4 and .65. These objects are held in this region by the 1:3 orbital resonance with Jupiter. An object in this resonace has its orbital eccentricty steadily increased by gravitational interactions with Jupiter until it eventually has a close encounter with an inner planet that breaks the resonance. Some Alindas, such as 4179 Toutatis, have perihelia very close to Earth's orbit resulting in a series of close encounters at four-year intervals. )
The 2004 approach is particularly interesting. 0.0104 Astronomical Unit equals about 1.5 millions of kilometers from us. Seen from Toutatis, the Earth will be as large in the sky as the Moon is from the Earth, and from Earth it will be large enough that the best telescopes will start resolving its apparent size.
Discovered by accident in 1989 while photographing Jupiter's fainter satillites, the discoverers named the asteroid after a Celtic/Gallic god whose name is invoked often in the well known comic book series "Les Aventures d'Asterix," set in ancient Gaul. Toutatis is the protector of Asterix and his compatriots, who fear nothing except that someday the sky may fall on their heads.)
The Sep. 29, 2004, approach is the closest in this century of any known asteroid at least as large as Toutatis. The vast majority of asteroids, and all the planets, spin about a single axis, like a football thrown in a perfect spiral, but Toutatis tumbles like a flubbed pass.
Being in the Heart of Chicago, it will be practically impossible for me to even attempt to target Toutatis, but some of you in darker skies have a good chance to observe it. If you do, please do post it here.