Author Topic: Strong arguments versus weak arguments.  (Read 130263 times)

Offline Count Zero

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Offline Bob B.

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Re: Strong arguments versus weak arguments.
« Reply #436 on: October 10, 2012, 09:45:13 AM »
I've seen only one total solar eclipse (February 26, 1979 in Oregon along the Columbia River east of the Cascades) and was surprised that the sky didn't get as dark as I expected. Only the planets and brighter stars were easily visible even though I had dark-adapted my eyes before totality. The sky was a very dark blue but not quite black. The horizon was bright in every direction, and only the center of the sun (moon, actually) looked completely black. I doubt it was actually darker than anywhere else in the sky, it was undoubtedly an optical illusion due to the sharp contrast with the corona at the moon's edge.

I've seen three eclipses and I've never been able to see anything other than Venus, Jupiter and Mercury.  It's never gotten dark enough to see stars.  As far as I know, no one around me was able to see stars either.

Offline ka9q

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Re: Strong arguments versus weak arguments.
« Reply #437 on: October 10, 2012, 10:55:08 PM »
I was at Kanarrahville, Utah recently for Ground Zero of this year's annular eclipse.  It got eerily dark, but not so dark that you could see stars.  The guy next to me photographed a jet contrail transiting the eclipse.  It was a pretty striking photograph.
And we were on the south rim of the Grand Canyon. It didn't really get dark at all, absolutely nothing like a total eclipse, even though it got noticeably dim. I had hoped the sun would be low enough in elevation to photograph it above the canyon without a filter, but this was not possible.

I also watched Venus transit the sun as it set here in San Diego, ready to snap a picture through my telescope, again without a filter. I was unable to do it until the sun was directly on the horizon; in fact only my first picture actually captured Venus, then it was below the trees.

Offline ka9q

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Re: Strong arguments versus weak arguments.
« Reply #438 on: October 10, 2012, 10:59:44 PM »
I've seen three eclipses and I've never been able to see anything other than Venus, Jupiter and Mercury.  It's never gotten dark enough to see stars.  As far as I know, no one around me was able to see stars either.
And I'm wondering why that is. Is the corona bright enough to wash them out, or is it light scattered by the earth and atmosphere from outside the umbra?

I tend to think the latter. During the 1979 eclipse the horizon was rather bright in every direction. It must have been the source of the light that kept the sky a dark blue rather than black, even in mid-totality.

Still, it's easily one of the most impressive sights anyone can witness from the earth's surface. Those last few seconds before totality are as if someone's turning down the house lights on a dimmer. We could see the umbra rushing toward us, and I almost felt like ducking.



Offline Count Zero

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Re: Strong arguments versus weak arguments.
« Reply #439 on: October 11, 2012, 10:28:09 AM »
In the last momensts before totality, when the sun is 99% covered, you still have more light than a brightly-lit room.  It's roughly the same light-level you would have if you were standing on a moon of Saturn.

When totality comes, you're going from well-lighted-room to darkness - but only for a couple of minutes; and you're spending a significant amount of those minutes looking at bright things like the solar corona and the horizon.

Your eyes simply do not have the opportunity to adapt enough to see stars.

I've seen two totol eclipses, and both times I was too busy screaming and jumping around to even think about looking for stars.  I'll probably be the same way in 2017.  I can see the stars on any clear night.  I'll want to be looking at the corona & horizon!
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Offline Glom

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Re: Re: Strong arguments versus weak arguments.
« Reply #440 on: October 11, 2012, 10:34:25 AM »
In the last momensts before totality, when the sun is 99% covered, you still have more light than a brightly-lit room.  It's roughly the same light-level you would have if you were standing on a moon of Saturn.

When totality comes, you're going from well-lighted-room to darkness - but only for a couple of minutes; and you're spending a significant amount of those minutes looking at bright things like the solar corona and the horizon.

Your eyes simply do not have the opportunity to adapt enough to see stars.

I've seen two totol eclipses, and both times I was too busy screaming and jumping around to even think about looking for stars.  I'll probably be the same way in 2017.  I can see the stars on any clear night.  I'll want to be looking at the corona & horizon!

And then the flash and you go blind.

Offline DataCable

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Re: Strong arguments versus weak arguments.
« Reply #441 on: October 11, 2012, 07:50:01 PM »
And then the flash and you go blind.
June Wheeler: Like my uncle Tito used to say, "It's always darkest just before the dawn."
[beat]
Bob Wheeler: Burned out his retinas starin' into an e-clipse.
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Offline ka9q

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Re: Strong arguments versus weak arguments.
« Reply #442 on: October 11, 2012, 08:49:12 PM »
Your eyes simply do not have the opportunity to adapt enough to see stars.
During the 1979 eclipse I actually tried to keep my eyes closed as much as possible between first and second contact so they'd be dark adapted for totality. I figured I could still see the entire partial phase after totality. I think I began really watching only in the last minute or so before totality, but even then I couldn't really see stars. But the fact that the sky was a dark blue rather than black says I couldn't have been too badly adapted to the dark.

Offline Zakalwe

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Re: Strong arguments versus weak arguments.
« Reply #443 on: October 12, 2012, 03:10:05 AM »
We just need some hoax believers now......

http://apollohoax.net/bingo/


Is this game still 'active'..? Because we can expect a nice chap soon (Edwardwb1001), really convinced that NASA faked it all. His best shot (I presume) is the BBC 1970 interview with Neil Armstrong done by Patrick Moore.

He questions Collins' statement regarding the stars, and Armstrong being unable to see any on the supposed long trip to the moon. Why an astronomer such as Moore thinks that there should have been stars brightly visible in the lunar sky, so much, that he thought they might even be visible in the solar corona. Et cetera, et cetera.

Nothing new, then?

Dunno if the bingo is still active. Maybe eddy can reactivate it.

Well....we've had the blast crater already.....
"The strain of anti-intellectualism has been a constant thread winding its way through our political and cultural life, nurtured by the false notion that democracy means that 'my ignorance is just as good as your knowledge.' " - Isaac Asimov