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Author Topic: Will we eventually see the dark side of the moon?  (Read 4714 times)

Offline chris

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The moon is phase locked in its rotation so that one complete moon-cycle (orbit of the Earth) coincides with one complete revolution of the body. Consequently it always shows us the same face.

But as the moon moves further from the Earth, which is happening at the rate of about 3cm per year due to the moon accelerating, will it eventually reach a position whereby we can see its dark side? If so, when?

Chris


 

Offline dentstudent

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Will we eventually see the dark side of the moon?
« Reply #1 on: 05/12/2008 08:49:15 »
Chris - the question should be "will we ever see the FAR side of the moon". There is no "dark" side - or rather there is a dark side, but it's not always facing away from us, as in the case of a new moon. But the "far" side is always facing away.
« Last Edit: 05/12/2008 12:23:26 by dentstudent »
 

Offline RD

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Will we eventually see the dark side of the moon?
« Reply #2 on: 05/12/2008 11:10:52 »
According to these articles the answer is no ...

Quote
The Moon's tidal forces on our planet continue to slow Earth's rotation. Every century, the length of our day increases by about one and a half milliseconds. (To keep up, earthlings invented leap seconds, but that's another story for another afternoon.) Meanwhile, the Moon's orbit is continuing to grow, by about one and a half inches per year, and so the lunar month is getting longer. What's going on is that the Moon is trying to get even and give Earth its own far side. That will happen when Earth's rotation rate has slowed enough to be equal to the Moon's orbital period. The Earth-Moon system will then have achieved a "double tidal lock." This never-invented wresting hold may sound rare, but it's actually common, particularly among double-star systems in our galaxy. Right here in our own backyard, Charon has managed to lock Pluto just as Pluto has locked Charon.

By the time the Moon tidally locks Earth, the system will have slowed down so much that the Earth day and the lunar month will both last almost fifty, present Earth days, greatly simplifying the calendar. Long before that, though, the Sun will become a red giant and vaporize the Earth-Moon system. But let's ignore that complication.
http://findarticles.com/p/articles/mi_m1134/is_3_115/ai_n26823967/pg_2


Quote
Earth's rotation will continue to slow down, and the Moon will continue to spiral away until the Earth day exactly equals the lunar month. At that time, one Earth rotation will last over 1000 hours, which would require 4 million leap seconds per day. No need to panic just yet. You have over a trillion years to think about it.
http://research.amnh.org/~tyson/18magazines_tidalforce.php
« Last Edit: 05/12/2008 11:22:26 by RD »
 

Offline Don_1

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Will we eventually see the dark side of the moon?
« Reply #3 on: 05/12/2008 12:19:52 »
Yes you can see the Dark Side of The Moon, here you are:

Dark side of the Moon, Pink Floyd
 

paul.fr

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Will we eventually see the dark side of the moon?
« Reply #4 on: 05/12/2008 12:58:38 »
I prefer Monn!
 

Offline dentstudent

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Will we eventually see the dark side of the moon?
« Reply #5 on: 05/12/2008 13:13:57 »
I prefer Monn!

touché my friend!
 

Offline Soul Surfer

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Will we eventually see the dark side of the moon?
« Reply #6 on: 05/12/2008 23:50:02 »
Chris no the moon is distorted by the fact that it is locked with one face towards us. It has a bulge on the side towards the earth so it effectively "knows" which way it is pointing so as the moon's orbit gets slower the rotation period gets slower too.
 

Offline chris

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Will we eventually see the dark side of the moon?
« Reply #7 on: 08/12/2008 20:44:15 »
But the moon is speeding up, not slowing down.

chris
 

Offline RD

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Will we eventually see the dark side of the moon?
« Reply #8 on: 09/12/2008 09:43:57 »
The moon's orbital period has slowed ...

Quote
Dr Eriksson, of the Australia National University in Canberra, explains the evidence as due to variations in the pull of the Moon depending how far or how close the satellite was to Earth in its orbit.

He told BBC News Online: "In my mind this represents unambiguous evidence for tides on Earth some 3,200 million years ago, and implies the presence of the Moon in orbit around the Earth at that time."

The analysis of the tidal patterns also suggests that the duration of the lunation, the length of the lunar month, was 20 days as opposed to the 27.5 days today.  
http://www.cyberconf.org/~cynbe/facts/monthgrowth.html
« Last Edit: 09/12/2008 09:47:35 by RD »
 

Offline chris

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Will we eventually see the dark side of the moon?
« Reply #9 on: 09/12/2008 21:09:23 »
Sorry - I was misled by the use of the word "slowed" - the period has "increased" because the moon has speeded up. PAradoxical as it sounds this is because the moon feels a force from the tidal bulge on Earth and this accelerates it. Consequently it moves further from Earth - hence the migration away by 3cm per year.

Chris
 

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Will we eventually see the dark side of the moon?
« Reply #9 on: 09/12/2008 21:09:23 »

 

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