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Prior to July, 1995 ZetaTalk described the Trailing Moons of Planet X and again in late Dec, 2001 ZetaTalk stated that the Moons of Planet X swirled behind, rather than orbit, Planet X, due to the periodic rapid passage it took it passing one of its suns. On April 23, 2002 the New York Times reported that when asteroids were discovered to have moons, or were of equal size to each other, this was the behavior.

Why would such a moon pattern perpetuate itself? Does Planet X not come to a virtual stop at the mid-point between its two foci? Having established a swirl behind the planet, the moons have two factors preventing a return to the normal orbital pattern of moons around a planet. First, their swirl perpetuates itself. The speed is dictated not only by the normal rotation around a gravitational master that attractants in the vicinity would create, it is dictated by the need to move away from the other moons in the swirl. Second, the larger moons in the cluster are perpetually trying to reach a closer proximity to their planet, the point where the repulsion force between the moon and its planet creates a stalemate. Being the larger moons, they push smaller moons away from their path, but this pushing action, in space, has the effect of causing them both to move, thus not only increasing and perpetuating their swirling motion, but also pushing the larger moon away from the planet it seeks to come closer to.

Abundance of Cometlike Objects With Moons Stuns Experts
The New York Times
April 23, 2002

Even small cometlike bodies at the edge of the solar system often have companion moons, to the surprise of astronomers who cannot yet explain how such tenuous gravitational pairings formed. Writing in the current issue of the journal Nature, a team of American and French astronomers describe the looping elliptical orbits of 1998 WW31, a small icy clump 4.3 billion miles from the Sun, and its moon. The pair is part of the Kuiper Belt, a ring of debris beyond the orbit of Neptune. When a Kuiper Belt object is nudged by a passing object's gravity and falls into the inner solar system, it becomes a comet.

Discovered four years ago, 1998 WW31 is one of more than 500 bodies that have been cataloged in the Kuiper Belt. In follow-up observations in 2000, astronomers led by Dr. Christian Veillet of the Canada-France-Hawaii Telescope in Kamuela, Hawaii, noticed that 1998 WW31 appeared elongated, like a blurry peanut. Comparing their images with those taken earlier, they found that the shape of the peanut changed over time, suggesting the motion of a moon around 1998 WW31. The astronomers announced the discovery last year, the first known around a Kuiper Belt object, unless one counts Pluto's moon Charon. (Some regard Pluto as the largest of the Kuiper Belt objects.)

With help from new photographs by the Hubble Space Telescope, the same team of astronomers has now mapped out the trajectories. Roughly the same size, 1998 WW31 is estimated at 75 to 90 miles wide; its moon is 60 to 75 miles wide and the two twirl around each other in a slow, highly elliptical dance. At their closest, they pass 2,500 miles from each other. At their most distant, they are 25,000 miles apart. They take 570 days to revolve around each other. "Their orbital motion is very, very eccentric," Dr. Veillet said. Astronomers once thought the gravitational pull of small bodies like asteroids and comets to be too slight to hold onto moons. In 1994, they were astonished when photographs from NASA's Galileo spacecraft revealed a tiny moon circling the asteroid Ida. A handful more moons have been discovered since among the thousands of asteroids between the orbits of Mars and Jupiter.

Moons around Kuiper Belt objects may be unexpectedly common. In the past year, astronomers have found moons about six more Kuiper Belt objects, and they have not yet examined most of them. "That's the extraordinary thing about this," said Dr. David Jewitt, a professor of astronomy at the University of Hawaii and one of the scientists who found the first Kuiper Belt object in 1992. No one predicted the observed abundance of moons. "It just happened," he said. Low-speed collisions between two Kuiper Belt objects may dissipate enough energy to allow the two to go into orbit around each other. A collision could also split one of the objects into a pair. "Then the details after that are hazy," Dr. Jewitt said. Now, most Kuiper Belt objects are too small, dim and distant for astronomers to learn much about them. They could get precise measurements of the sizes of 1998 WW31 and its moon when their orbits turn edge-on toward Earth, and one passes directly in front of the other. Astronomers have plenty of time to get ready, but many will not be alive to observe it. The earliest the eclipses may occur is around 2050. "I think I'm not likely to be," said Dr. Veillet, 54.