I beleive that it was Ludwig who has recently asked a few questions about
Solar System mechanics. This review/reference is from a weekly internet
mailing that includes reviews from ALL areas of science. (NOT to be
confused with the weekly postal newsmagazine 'Science News'.
DAILY SCIENCE NEWS BRIEFS are now posted at the SCIENCE-WEEK
website. You can link to the daily news page at:
<A HREF="http://scienceweek.com/daily.htm";>DSN Briefs</A>
Access to the daily news page is free. The daily news briefs
appear as much as 10 days before Science-Week.
10. ON CHAOS THEORY AND THE STABILITY OF OUR SOLAR SYSTEM
Ordinarily, a physical system is a system in which future states
can be predicted from prior states. But not all physical systems
exhibit such predictability. The term "chaos theory" refers to a
theory of unpredictable behavior arising in a system that obeys
deterministic laws but exhibits unpredictability. The essential
idea is that in certain systems small perturbations may produce a
cascade of larger perturbations, so that eventually the behavior
of such systems cannot be predicted from prior states no matter
if the systems appear simple and obey deterministic laws.
.... ... Adam Frank (University of Rochester, US) reviews
considerations of our solar system in terms of chaos theory. The
solar system may have lost several planets, and Mercury or Mars
might be the next planets to be ejected from their orbits.
Mercury has a small but finite chance of being ejected after a
close encounter with Venus. The essential idea is that due to the
gravitational influence of the other planets, the orbit of a
planet may become more and more eccentric over time, finally
cross the orbit of another planet, with the less massive planet
ejected from the solar system. There is a slight possibility that
the orbit of Mars will someday cross the orbit of Earth, with
Mars ejected from the solar system because of its lower mass. The
author suggests that under the influence of chaos theory our
understanding of planetary motion has been considerably trans-
formed, and the solar system is no longer viewed as a stable
clock, but rather as a dynamic and infinitely complex entity.
QY: Adam Frank, Univ. of Rochester, Dept. of Physics 716-275-4356
(Astronomy May 1998)
It's no accident that stressed Chuck Britton
spelled backwards is desserts. britton@odie.ncssm.edu