GSFC: LRO Reveals 'Incredible Shrinking Moon'

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bystander
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GSFC: LRO Reveals 'Incredible Shrinking Moon'

Post by bystander » Thu Aug 19, 2010 8:28 pm

LRO Reveals 'Incredible Shrinking Moon'
NASA GFSC | Lunar Reconnaissance Orbiter | 19 Aug 2010
Newly discovered cliffs in the lunar crust indicate the moon shrank globally in the geologically recent past and might still be shrinking today, according to a team analyzing new images from NASA's Lunar Reconnaissance Orbiter (LRO) spacecraft. The results provide important clues to the moon's recent geologic and tectonic evolution.

The moon formed in a chaotic environment of intense bombardment by asteroids and meteors. These collisions, along with the decay of radioactive elements, made the moon hot. The moon cooled off as it aged, and scientists have long thought the moon shrank over time as it cooled, especially in its early history. The new research reveals relatively recent tectonic activity connected to the long-lived cooling and associated contraction of the lunar interior.
Evidence of Recent Thrust Faulting on the Moon Revealed by the Lunar Reconnaissance Orbiter Camera - TR Watters

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Re: GSFC: LRO Reveals 'Incredible Shrinking Moon'

Post by Guest » Thu Aug 19, 2010 8:34 pm

I heared before that moon is going away from earth slowly, according to laser measurements. Now, could it be that laser measurements actually show moon shrinking?

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neufer
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Re: GSFC: LRO Reveals 'Incredible Shrinking Moon'

Post by neufer » Thu Aug 19, 2010 9:07 pm

Guest wrote:I heard before that moon is going away from earth slowly, according to laser measurements.
Now, could it be that laser measurements actually show moon shrinking?
No.
http://twitter.com/elakdawalla/statuses/21597172671/ wrote:
Watters: <<"Based on the size of the scarps, we estimate the distance between the moon's center and its surface shrank by about [100 m]">>
Most of the 100 meter shrinkage of the moon's radius took place a few billion of years ago. The Moon's distance to the Earth is currently increasing by 100 meters every 2,632 years (; consistent with the lengthening of Earth's day by about 15 microseconds every year).
http://en.wikipedia.org/wiki/Moon wrote:
<<Gravitational coupling between the Moon and the bulge nearest the Moon acts as a torque on the Earth's rotation, draining angular momentum and rotational kinetic energy from the Earth's spin. In turn, angular momentum is added to the Moon's orbit, accelerating it, which lifts the Moon into a higher orbit with a longer period. As a result, the distance between the Earth and Moon is increasing, and the Earth's spin slowing down. Measurements from lunar ranging experiments with laser reflectors left during the Apollo missions have found that the Moon's distance to the Earth increases by 38 mm per year (though this is only 0.10 ppb/year of the radius of the Moon's orbit). Atomic clocks also show that the Earth's day lengthens by about 15 microseconds every year, slowly increasing the rate at which leap seconds must be added to the calendar.>>
Art Neuendorffer

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Chris Peterson
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Re: GSFC: LRO Reveals 'Incredible Shrinking Moon'

Post by Chris Peterson » Thu Aug 19, 2010 9:14 pm

Guest wrote:I heared before that moon is going away from earth slowly, according to laser measurements. Now, could it be that laser measurements actually show moon shrinking?
No. The increasing orbital radius of the Moon wasn't detected by rangefinding, but is understood in terms of angular momentum transfer. Simple orbital dynamics means it is also measurable in terms of a changing orbital period- something readily seen in geological data. The Moon used to be a LOT closer- by more than a lunar diameter, and therefore inexplicable in terms of lunar shrinkage.
Chris

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Henning Makholm
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Re: GSFC: LRO Reveals 'Incredible Shrinking Moon'

Post by Henning Makholm » Fri Aug 20, 2010 1:09 am

Chris Peterson wrote:The increasing orbital radius of the Moon wasn't detected by rangefinding, but is understood in terms of angular momentum transfer.
It has, however, been confirmed by laser rangefinding.
The Moon used to be a LOT closer- by more than a lunar diameter, and therefore inexplicable in terms of lunar shrinkage.
Quite. In fact, at the current rate of recession, it only takes about 100 million years for it to move a lunar diameter outwards.
Henning Makholm

deathfleer

Re: GSFC: LRO Reveals 'Incredible Shrinking Moon'

Post by deathfleer » Wed Nov 13, 2013 10:10 pm

Mr. Nuefer , etc,
I would be very pleased if you could verify these two photos:-
http://www.akhwatmuslimah.com/wp-conten ... crack1.jpg

and
http://www.akhwatmuslimah.com/wp-conten ... elah-1.jpg

thanks

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neufer
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Re: GSFC: LRO Reveals 'Incredible Shrinking Moon'

Post by neufer » Wed Nov 13, 2013 11:50 pm

deathfleer wrote: Mr. Nuefer , etc,

I would be very pleased if you could verify these two photos:-
http://www.akhwatmuslimah.com/wp-conten ... crack1.jpg
and
http://www.akhwatmuslimah.com/wp-conten ... elah-1.jpg

thanks
They look legitimate to me.
Art Neuendorffer