During the 1950s, the campaign of main-stream science to discredit Velikovsky assured the public that the solar system was the epitome of stability---wayward planets were impossible. Then along came chaos theory which implied that the flight of a butterfly in Brazil could, in principle, affect weather in Canada. In effect, a slight change in initial conditions could, in the fullness of time, have very large effects. Now, it is generally admitted that the solar system is chaotic after all. Each planet is subject to the tiny, butterfly-like gravitational tugs of the other planets, especially Jupiter. Given enough time, these gravitational nuances can result in the ejection of a planet from the solar system—and may already have done so in the past!

Mercury and Mars are the most vulnerable on a billion-year time scale. In the case of Mercury, its orbit will become more and more elliptical according to computer simulations. Eventually a close gravitational encounter with Venus is possible. This could send Mercury careening off into deep space. The probability of this happening is only 1 in a 1000 over 5 billion years, but it is not zero.

Mars might likewise be ejected by a passing nudge from earth. However, this encounter could go the other way. Depending upon the celestial dynamics of the encounter, Mars might gravitationally fling earth out into the Galaxy, and our planet would truly become "Spaceship Earth."

Source: Frank, Adam
"Crack in the Clockwork"
Astronomy, 26:54, May, 1998

Comment. The computer simulations used in the foregoing study have to assume that we know all the forces acting in the solar system. This may not be the case according to the next item.

THE FORCE IS WITH THEM

The communication loop between earth-based ground stations and interplanetary spacecraft allows extremely accurate measurements of the radial velocities of these distant man-made machines. As these spacecraft hurtle toward the fringe of the solar system, the visible sun dwindles to a small, bright point, and its gravitational field falls off as the inverse square of the distance. At least that is what is supposed to happen.

Four far-flung spacecraft, (Pioneer 10, Pioneer 11, Ulysses, and Galileo, are experiencing a mysterious decelerating force not encompassed by the Law of Gravitation. It's a tiny force, but it seems to be real. Making it even more puzzling is the fact that it is decreasing according to the inverse of distance from the sun rather than the inverse square. Is it a non-solar force? Is it "new" physics? Or maybe just an artifact of the spacecraft and ground-based equipment?

The fact that four spacecraft feel its tugging suggests the force is real. But the motions of the distant planets do not seem to be affected by it. So, everyone is perplexed.

Source: Schilling, Govert
"Spacecraft Motions Puzzle Astronomers"
Science, 281:1581, 1998

Source: Seife, Charles
"If the Force Is with Them. . ."
New Scientist, p. 4,
September 12, 1998

Source: Browne, Malcolm
"After Study, Mystery Force Remains One"
New York Times, September 17, 1998

Cr. M. Colpitts