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LAhiker
Social climber
Los Angeles
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Aug 20, 2017 - 11:35pm PT
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It seems more than a coincidence that the moon is at the perfect distance and has the exact diameter to block exactly the suns diameter!? Is it known how this is achieved? Is the moons orbit determined by both the earths and the suns gravitational pull?
Apparently it is a coincidence. The moon appearing to be the same size in the sky as the sun is due to its being around 400 times smaller than the sun but 400 times closer to earth than the sun. But because the moon's orbit around the earth is slightly elliptical rather than being completely circular, sometimes the moon is closer or further than that average distance. The linked-to piece, written just before a 2012 solar eclipse, also points out that this coincidence won't last forever -- in millions of years the moon's orbit will be slightly bigger.
https://blogs.scientificamerican.com/life-unbounded/the-solar-eclipse-coincidence/
From the piece:
"The Moon happens to be about 400 times smaller than the Sun, but the Sun happens to be about 400 times further from the Earth than the Moon is. So simple geometry tells us that the apparent disk of the Moon is almost exactly the size of the apparent disk of the Sun. Of course this match is not always quite the same, the Earth orbits the Sun in a modestly non-circular, elliptical, path and so our nearest and furthest distances (perihelion and aphelion) differ by about 3.3%. And the Moon's orbit has a roughly 10% difference between its near and far point to us, so the precise degree of total solar eclipse will vary a little as the apparent sizes of Sun and Moon vary."
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TwistedCrank
climber
Released into general population, Idaho
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Aug 21, 2017 - 07:23am PT
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Ancient astronauts.
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Chaz
Trad climber
greater Boss Angeles area
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Aug 21, 2017 - 08:14am PT
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The idiot on the TV News this morning described this as an "atmospheric event". Maybe he knows something we don't, and the moon's going to be a hell of a lot closer than we think.
Don't look at it, though. Whatever you do.
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Lorenzo
Trad climber
Portland Oregon
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Aug 21, 2017 - 09:09am PT
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First contact in Silverton OR.
9:05
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Ed Hartouni
Trad climber
Livermore, CA
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Aug 21, 2017 - 09:12am PT
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maybe an idiot, but there is a lot of observational work surrounding this eclipse relevant to the atmosphere, the Sun being the major energy source for atmospheric phenomena...
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john hansen
climber
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Aug 21, 2017 - 09:56am PT
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Was just looking at the eclipse from the Big Island Hawaii.
Only about fifteen percent here though.
Would love to see totality some day. Have fun.
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DonC
climber
CA
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Aug 21, 2017 - 10:23am PT
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I'm at Navy Beach at Mono Lake. With a few wispy clouds in the sky already, no noticeable difference.
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Ghost
climber
A long way from where I started
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Aug 21, 2017 - 10:37am PT
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The major effect of the eclipse here in Seattle was that every office tower in the downtown area was empty, and every sidewalk was packed.
Most people have now gone back to work. Except my staff. Lazy buggers are still out there somewhere. "Oh, we're just going to go to the park to watch it." It was only after they all left that I realized that the closest park is about half a mile away.
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Ken M
Mountain climber
Los Angeles, Ca
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Aug 21, 2017 - 10:59am PT
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I'm curious, inasmuch as I don't go to church, how accurate were churches and other religious groups in predicting this eclipse? After all, they purport to have superior knowledge of the Universe, compared to science......
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SC seagoat
Trad climber
Santa Cruz, Moab, A sailboat, or some time zone
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Aug 21, 2017 - 11:04am PT
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LOVING the temp drop here in Moab. Relief!
Puppy even went to sleep!
Susan
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rottingjohnny
Sport climber
Sands Motel , Las Vegas
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Aug 21, 2017 - 12:08pm PT
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Was in court this morning and the judge took a 30 min. eclipse break...
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fear
Ice climber
hartford, ct
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Aug 21, 2017 - 12:10pm PT
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That was cool in CT.... two #10 arc-welding filters worked great although a little dark.
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neebee
Social climber
calif/texas
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Aug 21, 2017 - 12:57pm PT
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hey there say... neat report, tami, with the crows! :))
also, good temp, then, for susan...
and hahaha, those 'workers going to the park'... :)
well, here, i was out at the ' right time ' but all i got was the
really NEAT color change of the greens in the yard, and i loved it!
nothing showed up, on the ground, through leaves, etc, as to images, though...
even a few silhouettes just stayed round...
but, i loved it and had fun...
felt like a 'rainy day' though it was not...
the over cast helped there, too, a bit for all of this,
adding to the ambiances... :)
will love to hear more shares, later...
:)
thank you all!
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donini
Trad climber
Ouray, Colorado
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Aug 21, 2017 - 01:05pm PT
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Yep, an event where the best viewing was generally in Trumplandia. I'll bet the locals were surprised that it came off just as the elitist scientists predicted.
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fear
Ice climber
hartford, ct
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Aug 21, 2017 - 01:13pm PT
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Ra's sun chariot lost a wheel. No big deal.
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Wayno
Big Wall climber
Seattle, WA
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Aug 21, 2017 - 01:24pm PT
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I took the dogs for a walk and the park was full of people with various devices being fascinated. I walked under some trees and instead of seeing the shadows of leaves on the ground all I saw was hundreds of little light crescents scattered among the shadows. Rather surreal.
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cragnshag
Social climber
san joser
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Aug 21, 2017 - 01:59pm PT
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totall(it)y cool!
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BooDawg
Social climber
Butterfly Town
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Aug 21, 2017 - 02:04pm PT
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Here is one of my pix taken from Corvallis, OR. More pix and a narrative to follow...
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