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- From: hrubin@pop.stat.purdue.edu (Herman Rubin)
- Subject: Re: averting doom
- Message-ID: <C06Er2.F0F@mentor.cc.purdue.edu>
- Sender: news@mentor.cc.purdue.edu (USENET News)
- Organization: Purdue University Statistics Department
- References: <JMC.92Dec29211051@SAIL.Stanford.EDU> <C05E2y.B7E@cs.uiuc.edu>
- Date: Fri, 1 Jan 1993 12:59:26 GMT
- Lines: 31
-
- In article <C05E2y.B7E@cs.uiuc.edu> scott@cs.uiuc.edu (Jay Scott) writes:
- >John McCarthy writes:
- >>By the way, it seems to me that if the above idea is sound, it settles
- >>the question of the stability of the solar system - in the negative.
-
- .......................
-
- >Without being so rash as to do any actual calculations, I
- >would guess that this does not say much about the stability
- >question. I would guess that an asteriod is so much more likely
- >to be ejected from the solar system, or smashed to dust by
- >collisions, or fall into a planet, than to be captured into
- >a destructive resonant orbit that the asteriods will all be gone
- >before they destabilize the solar system.
-
- From the standpoint of stability as precisely defined in the theory
- of dynamical systems, a gravitational system is not stable; the effects
- of a perturbation do not die out. It is, for example, quite possible
- that one of our space probes could alter the orbit of an asteroid so
- that the gravitational attraction of another asteroid could cause it
- to get a gravity boost from Jupiter which knocks it out of the solar
- systme. Even more so, a change of one micron/second in the earth's
- speed will eventually have a non-trivial effect on the paths of
- Venus and Mars. I have not made any attempt to calculate how long
- this will take.
-
- --
- Herman Rubin, Dept. of Statistics, Purdue Univ., West Lafayette IN47907-1399
- Phone: (317)494-6054
- hrubin@snap.stat.purdue.edu (Internet, bitnet)
- {purdue,pur-ee}!snap.stat!hrubin(UUCP)
-