Perhaps the most significant development of this line of research will be the finding that such objects also wind up following these same channels to plummet through the atmosphere and wreak havoc.More Moons Around Earth? It’s Not So LoonyOctober 29 1999 -- Earth has a second moon, of sorts, and could have many others. Cruithne, the 3-mile-wide (5-km) satellite, takes 770 years to complete a horseshoe-shaped orbit around Earth, and will remain in a suspended state around Earth for at least 5,000 years. Every 385 years, it comes to its closest point to Earth, some 9.3 million miles (15 million kilometers) away. Its next close approach to Earth comes in 2285. "We found new dynamical channels through which free asteroids become temporarily moons of Earth and stay there from a few thousand years to several tens of thousands of years," said Fathi Namouni, one of the researchers, now at Princeton University. Namouni’s colleague Apostolos Christou said, "At specific points in its orbit, it reverses its rate of motion with respect to Earth so it will appear to go back and forth." In his view, there are three classes of moons – large moons in near-circular orbits around a planet, having formed soon after the planet; smaller fragments that are the products of collisions; and outer, irregular moons in odd orbits, or captured asteroids like Cruithne. In the past year, astronomers have reported finding such objects around Uranus.
by Robin Lloyd
V.A. Firsoff (Valdemar Axel Firsoff, as it turns out) wrote a lot of books (I think he's dead, but perhaps not), including Strange World of the Moon published back in 1959, ten years before the manned landings started, and even before the first robotic landers.
A while back I picked up a used copy for $1.98 at the enormous chain bookstore, which had "Shimon Kaplan, Israel" on the flyleaf, or whatever that blank first page is called. Hard to figure, considering this is Grand Rapids Michigan, but it's not exactly like a message in a bottle.
Firsoff's book is interesting in that it shows the prevailing ideas about what would be found on the Moon (it was already believed during the 19th century, and more relevantly, by the 1920s and 1930s in Germany, that humans would visit the Moon). In a chapter "The Earth's Fair Child or a Foundling?" Firsoff blows off the idea that impact plays any role on the Moon, attributing its surface features to vulcanism, a view that died a quiet death in 1972, when a geologist first set foot on the Moon.
Due to his volcanism bias, which was an outgrowth of his uniformitarian bias, he wasn't able to accept that the Moon's impact craters were in fact from impact, and attributes them instead to the Moon's capture by the Earth (as well as contraction of the lunar sphere), apparently after having been tossed off by the overspin condition very early in the history of the Earth (see Thomas Van Flandern for a similar articulation). He appears to envisage three encounters between the formed Moon and the Earth, resulting in temporary capture twice leading to the eventual outright capture.
...the Moon clearly could not have been the satellite of the Earth then, for a total period of about 2,000 million years... Spurr points out that the face of the Moon shows two systems of great surface fractures, or faults, lying about 30 degrees from the two poles and trending from west-south-west to east-north-east. This is explained by him as a result of the halting of the Moon's rotation... Curiously, the face of the Earth, too, shows a similar structure, with the same general trend -- the Highland Boundary Fault... The poles of the Earth would also seem to have shifted place on at least three occasions, in the Cambrian, Permian, and (lastly) Quaternary Periods, brining ice and cold to previously warm lands... some mighty force made the crust of the Earth slip (the rotational stability of the axis of a mass as large as the Earth is enormous) and the position of the poles wobbled... there exists on the Moon a triple grid of surface fractures... perpendicular to each other within each grid, the grids being of different ages... Cambrian, Perm-Carboniferous, and Tertiary.Fascinating idea, based though it is on outmoded ideas about impact (i.e., Firsoff's view that there was no role for impact). He's basically given us a snapshot of the problems inherent with a fission origin (either by overspin or by impact), not least of which is that the fission origin also requires in orbit formation of the lunar sphere and capture by the Earth, while showing that capture is possible.
Here's Van Flandern's book (revised edition). FWIW, I don't agree with him regarding the origin of the moon, wonder how the EPH is an apparently frequent phenomenon while TVF provides no mechanism, and most notoriously, wonder how and why he remains a supporter of Richard Hoaxland's "face on Mars" nonsense:
Dark Matter, Missing Planets and New Comets:
Paradoxes Resolved, Origins Illuminated
by Tom Van Flandern
