The moon is shrinking. No, seriously.

reply to post by aboxoftrix


I am pretty sure they don't have to tell you what goes on with their missions to the moon NASA has secrets to you know

I read an article in the Guardian today about this - www.guardian.co.uk...

It's pretty interesting to think about. It's all too easy to imagine the moon as a cold, dead rock, but this suggests that there might still be heat in the core.

I wonder if the moon shrinking would affect tidal activity at all, or animal and human activity for that matter, as many have speculated that the moon affects us.

If the moon changes the tides in bodies of water, it seems reasonable to conclude that it could change us in some way, as the human body is around 60% water.


[edit on 20-8-2010 by Malvenkemo]

reply to post by Malvenkemo


I don't believe it does, as the mass stays the same. Furthermore, the change is relatively miniscule.

--airspoon

I not totally sure, but I thought that I had read somewhere, that the moon was actually putting distance between the Earth and itself, meaning that it was going further away.

Could this be why it is smaller?

My understanding was that the theory was based on the observation of wrinkles on the surface in photos from a NASA orbiter, the size of the moon measured from Earth wasn't a factor.

I do see your point Airspoon, however the moon is relatively small compared to the Earth yet, from my limited understanding, has a considerable effect on tidal activity. From that it could follow that a small change in the moon might cause a larger effect on Earth.

Of course I am no scientist (I'm a journalist as it happens), and this is all idle speculation on my part, but it's still rather interesting to think about.

reply to post by Malvenkemo


The moon's tidal effect is due to its gravitational force on the Earth. If the moon's mass is the same, its gravitational force is going to be the same, considering all of the other variables are the same. With that being said, the moon is slowing down and moving away from the Earth, which does effect tidal forces. It is this very tidal force that is causing the moon to slow down in its orbit, thus allowing it to move further out.

--airspoon

[edit on 20-8-2010 by airspoon]

Another link added today

Link

This is surprising, given the moon's relatively small size, said Pat McGovern, a geophysicist at the Lunar and Planetary Institute in Houston, Texas, who called the new findings a "blockbuster result."

"Small planetary bodies tend to lose their internal heat very quickly," said McGovern, who was not involved in the new research.

"Heat is what drives the overall evolution of a planet, and the moon is thought to have lost most of [its heat] long ago. But the idea that you have very young faulting going on is very exciting, because it's somewhat unexpected."

While the moon might still be shrinking, its rate of contraction is probably slowing, and shrinkage will eventually halt completely, study co-author Watters said.

reply to post by aboxoftrix


Very interesting.

...So if the moon can "shrink," does that mean the earth can too?

If the moon is 4.5 billion years old, and it has shrunk 600 feet in that time (from the NatGeog article,) the rate of change is barely measurable. This is a dynamic universe, it seems less surprising that the moon's size is not constant than if it was. The thing you need to concerned about is the rate -- if the North American plate is moving west at 2 centimeters per year, quite another if it were to suddenly move 30 miles.

Cool article, though, S&F, thanks!

[edit on 20-8-2010 by adjensen]