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KemiClarke subscribed to SpaceRip
(1 week ago)
From NASA's Scientific Visualization Studio. New images from NASA's Lunar Reconnaissance Orbiter (LRO) spacecraft show the moon's crust is being st...
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From NASA's Scientific Visualization Studio. New images from NASA's Lunar Reconnaissance Orbiter (LRO) spacecraft show the moon's crust is being stretched, forming minute valleys in a few small areas on the lunar surface. Scientists propose this geologic activity occurred less than 50 million years ago, which is considered recent compared to the moon's age of more than 4.5 billion years.
A team of researchers analyzing high-resolution images obtained by the Lunar Reconnaissance Orbiter Camera (LROC) show small, narrow trenches typically much longer than they are wide. This indicates the lunar crust is being pulled apart at these locations. These linear valleys, known as graben, form when the moon's crust stretches, breaks and drops down along two bounding faults. A handful of these graben systems have been found across the lunar surface.
We think the moon is in a general state of global contraction because of cooling of a still hot interior," said Thomas Watters of the Center for Earth and Planetary Studies at the Smithsonian's National Air and Space Museum in Washington, and lead author of a paper on this research appearing in the March issue of the journal Nature Geoscience. "The graben tell us forces acting to shrink the moon were overcome in places by forces acting to pull it apart. This means the contractional forces shrinking the moon cannot be large, or the small graben might never form."
The weak contraction suggests that the moon, unlike the terrestrial planets, did not completely melt in the very early stages of its evolution. Rather, observations support an alternative view that only the moon's exterior initially melted forming an ocean of molten rock.
In August 2010, the team used LROC images to identify physical signs of contraction on the lunar surface, in the form of lobe-shaped cliffs known as lobate scarps. The scarps are evidence the moon shrank globally in the geologically recent past and might still be shrinking today. The team saw these scarps widely distributed across the moon and concluded it was shrinking as the interior slowly cooled.
Based on the size of the scarps, it is estimated that the distance between the moon's center and its surface shank by approximately 300 feet. The graben were an unexpected discovery and the images provide contradictory evidence that the regions of the lunar crust are also being pulled apart.
"This pulling apart tells us the moon is still active," said Richard Vondrak, LRO Project Scientist at NASA's Goddard Space Flight Center in Greenbelt, Md. "LRO gives us a detailed look at that process."
As the LRO mission progresses and coverage increases, scientists will have a better picture of how common these young graben are and what other types of tectonic features are nearby. The graben systems the team finds may help scientists refine the state of stress in the lunar crust.
"It was a big surprise when I spotted graben in the far side highlands," said co-author Mark Robinson of the School of Earth and Space Exploration at Arizona State University, principal investigator of LROC. "I immediately targeted the area for high-resolution stereo images so we could create a three-dimensional view of the graben. It's exciting when you discover something totally unexpected and only about half the lunar surface has been imaged in high resolution. There is much more of the moon to be explored."
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"Wanna be my mango juice? I broke all my apples.."
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"You have a goat on your face...Awe-some"
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KemiClarke subscribed to davedays
(1 month ago)
Since I love you guys lyke sooew much, I flew to PA this weekend for 1 day just to film this video with Chris. Just edited it here in LA and decide...
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Since I love you guys lyke sooew much, I flew to PA this weekend for 1 day just to film this video with Chris. Just edited it here in LA and decided to throw it up now!! Remember my new EP "We're Just Kids" comes out on iTunes March 7th! This song is on the EP along with more new ones! Thanks for all your support. #werejustkids
My Twitter: http://www.twitter.com/davedays
Facebook: http://www.facebook.com/ddays
Chris' Channel: http://www.youtube.com/iamchrisc
Come see me play live in March! http://www.thedigitour.com
Lyrics:
She's walking over to me I'm too scared to move or look in her eyes
She wants to see me tonight
I'm counting down the minutes they pass like hours stuck in time
Stomachs filled with butterflies
(Is it cool if I kiss you)
I'm counting on chances
(Is it cool if I kiss you)
I'm waiting on time
Is it cool if I kiss you now maybe some way some how
Tell me that you want me more than I know
Hold your breath we don't need to know whats next
I just want to live this moment with you tonight
Can't sleep can't wait to wake up, no I can't wait to start my day
Knowing I will see your face
Over thinking feeling nervous hope I don't slip and screw this up
Worst of all I'd fall in love
Bridge:
I want to live this moment with you
I want this moment to last forever
(Is it cool if I kiss you)
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"I can eat computer text :P"
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