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Astronomy Picture of the Day -- Red Moon, Green Beam
NASA ^ | April 18, 2014 | (see photo credit)

Posted on 04/18/2014 9:44:08 AM PDT by SunkenCiv

Explanation: This is not a scene from a sci-fi special effects movie. The green beam of light and red lunar disk are real enough, captured in the early morning hours of April 15. Of course, the reddened lunar disk is easy to explain as the image was taken during this week's total lunar eclipse. Immersed in shadow, the eclipsed Moon reflects the dimmed reddened light of all the sunsets and sunrises filtering around the edges of planet Earth, seen in silhouette from a lunar perspective. But the green beam of light really is a laser. Shot from the 3.5-meter telescope at Apache Point Observatory in southern New Mexico, the beam's path is revealed as Earth's atmosphere scatters some of the intense laser light. The laser's target is the Apollo 15 retroreflector, left on the Moon by the astronauts in 1971. By determining the light travel time delay of the returning laser pulse, the experimental team from UC San Diego is able to measure the Earth-Moon distance to millimeter precision and provide a test of General Relativity, Einstein's theory of gravity. Conducting the lunar laser ranging experiment during a total eclipse uses the Earth like a cosmic light switch. With direct sunlight blocked, the reflector's performance is improved over performance when illuminated by sunlight during a normal Full Moon, an effect known as the real Full Moon Curse.

April 18, 2014

(Excerpt) Read more at 129.164.179.22 ...


TOPICS: Astronomy; Astronomy Picture of the Day; Science
KEYWORDS: apod; astronomy; lunareclipse; science
[Credit & Copyright: Dan Long (Apache Point Observatory) - Courtesy: Tom Murphy (UC San Diego)]

1 posted on 04/18/2014 9:44:08 AM PDT by SunkenCiv
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To: brytlea; cripplecreek; decimon; bigheadfred; KoRn; Grammy; steelyourfaith; Mmogamer; dayglored; ...
"That's No Moon!" (had to get the Death Star joke out of the way).
The Big One

2 posted on 04/18/2014 9:44:57 AM PDT by SunkenCiv (https://secure.freerepublic.com/donate/)
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To: SunkenCiv

“Fully operational battle station!”


3 posted on 04/18/2014 9:50:25 AM PDT by Darksheare (Try my coffee, first one's free..... Even robots will kill for it!)
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To: Darksheare

4 posted on 04/18/2014 10:04:58 AM PDT by rickmichaels
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To: SunkenCiv

Wow. That’s an astounding picture, and the data collected from “shooting the Moon” are wonderful as well.

That’s no Death Star!! ;-)


5 posted on 04/18/2014 10:20:00 AM PDT by TheOldLady
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To: TheOldLady

6 posted on 04/18/2014 10:25:28 AM PDT by uglybiker (nuh-nuh-nuh-nuh-nuh-nuh-nuh-nuh-nuh-nuh-nuh-nuh-nuh-nuh-nuh-nuh-BATMAN!)
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To: uglybiker

*Snort* [giggles]

Watch out! Old ladies can die laughing, you know!


7 posted on 04/18/2014 10:54:23 AM PDT by TheOldLady
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To: SunkenCiv

Good shot!


8 posted on 04/18/2014 11:16:14 AM PDT by TigersEye (Stupid is a Progressive disease.)
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To: SunkenCiv

I initially thought that could have been the laser from my rifle as I was pointing it at the Moon(was doing a demonstration for the kids).


9 posted on 04/18/2014 11:51:17 AM PDT by KoRn (Department of Homeland Security, Certified - "Right Wing Extremist")
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To: SunkenCiv

Lunar Asteroid Deflector Base (If al-NASAM does their job...)

10 posted on 04/18/2014 12:47:03 PM PDT by mikrofon (Reprise)
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