
Earth may once have had more than one moon, most probably two more, NASA scientists think.
Prevailing scientific consensus holds that the existing Moon was formed when a Mars-sized planet collided with the Earth 4.5 billion years ago, when the solar system was very young.
In a separate study, astrophysicist Matija Cuk of the University of British Columbia thinks the smallest possible moons, those only a few dozen miles across, could have lasted for up to a billion years at the Lagrangian points in the Moon's orbit.
Separate modelling work by Matija Cuk, an astrophysicist at the University of British Columbia in Canada, suggests small, asteroid-sized objects a few tens of kilometres across would have lasted the longest as Trojan satellites. Cuk estimates these 'lost moons' might have circled Earth for a billion years or more after the Moon's formation.
Very cool to think off. Of course the surface of the Earth was basically boiling lava then.
Hence, three moons but no-one to see them!
So, what about our one remaining moon, will it ever leave us, too? A quick look around the web, the answer seems to be "no", barring some cosmic event as yet unforeseen.
We should start REXing ASAP.
(Civ4 rhetoric)
Thanks all for the interesting questions and input.
You're in Easy Mode. If you prefer, you can use XHTML Mode instead. |