Oort cloud
Pim van Meurs (entheta@eskimo.com)
Tue, 29 Sep 1998 20:31:18 -0700I just bought a copy of Scientific American, September 1998 and on pp. 84-89, there is an interesting article about the Oort cloud. It is fascinating how scientists analyzed the data and came to the conclusion of the existance of the Oort cloud. It's even more fascinating how based upon the assumption of the existance of the Oort cloud, a computer simulation showed that a disturbance of the Oort cloud by a passing star would lead to a comet shower 300 times the normal rate and the shower would last 2-3 million years.
Using Helium 3 isotopes, other researchers found that the rate of comets increased sharpl yat then end of the Eocene epoch, about 36 million years ago and decreased slowly over about 2-3 mullion years. The Eocene epoch is also identified with a moderate biological extinction event and several impact craters have been dated to this time.
Fascinating how careful evaluation of the data can come up with so much knowledge about something which cannot be observed directly at this time.
Pim