Science marches on. New studies of lunar material might call into question the collision theory of lunar formation. If a Mars sized object struck the Earth early in it’s history, then today’s Moon might be too wet.
It’s odd to think of the Moon as too wet, or indeed, to think of it as wet at all. Recent discoveries have indicated there is a lot of water there. Some very recent work has indicated, however, that the Moon may be too wet!
Scientists at the Carnegie Institute for Science have examined rocks brought back from the Moon by Apollo astronauts, and have come to the conclusion that there is more water on the Moon than would be allowed by the currently accepted collision theory. (I think it’s great that 35 years and more after the last Apollo mission to the Moon, we’re still doing science with the lunar material the astronauts brought back. Science that is still cutting edge.)
This article at Astronomy Now Online gets into more detail about the new research and what it means for our current thoughts on the formation of the Moon.
We might have to reconsider our ideas about the collision theory. Perhaps we’ll change the ideas about the amount of water in lunar rocks and how it might have gotten there. We’ll definitely learn more about how the early solar system was formed, the forces that acted on bodies then, and how those reactions have echoed down to our time. Theories about the very nature of the Earth-Moon system may change, or perhaps the theories that the current science maintains will change to merge the data into coherent thoughts about what happened 4.5 billion years ago.
If the Moon hadn’t struck the young Earth (if, indeed, that’s what happened), things might be very different here. The interactions of the tides created by the Moon may have been a key force in the development of life. The Moon was much closer to the early Earth than it is now, and tidal action was much more dramatic than what we experience today. Huge tidal surges in the past drove water well inland, and then drained back out. Evolution may have gotten it’s kick-start with these massive tides.
The scientists keep working on the subject, and we’ll keep refining our thoughts on the matter. This new work suggests we don’t really know what happened, exactly, but we are learning more each time someone cracks open a rock and says “let’s see what we find!”. A wetter than expected Moon tosses out some old ideas, creates new ones, and gives us pause. We can step outside and look up, and on a clear night we can stand and wonder, looking right at it… the Moon. You can almost reach out and touch it. And billions of years ago, it was even closer!
The Sun sustains life on Earth, but it might be the Moon that to which we owe our very existence. We continue asking the questions, and science gives us the answers. All we have to do is ask the right questions.