Solar eclipse to be seen in Western US on May 20, 2012

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Ed Hartouni

Trad climber

Livermore, CA

May 18, 2012 - 09:21pm PT

here's an image of the Sun today around 6pm

50mm + 2x + 1.4x + ND400 f16 1/8000s exposure at ISO 100

50mm + 2x + 1.4x + ND400 f5.6 1/6400s exposure at ISO 100

nature

climber

May 18, 2012 - 09:36pm PT

But it's not really the moon, right? :)

nope!

*giggle*

aguacaliente

climber

May 18, 2012 - 11:27pm PT

For the pinhole projection don't you need a dark enclosure to get decent contrast? I've seen recommendations for obtaining or constructing a five foot long cardboard box.

http://www.exploratorium.edu/eclipse/how.html

Take a poster tube or other long cardboard tube or box. At the top end, tape a pinhole made from aluminum foil. At the bottom end, tape a piece of paper for the projection screen. At the bottom, cut away about a third of the tube, for a length of a few inches. This is the viewing window that lets you look down at the paper.

Make it now and you can test it tomorrow when the sun is out. I'm going to go make one now.

Another cool thing is that if you look at the shadow under a tree, the leaves form apertures moving back and forth in the wind, and make little images of the circular disk of sun. During a partial eclipse the dappled shadow of leaves turns into a swarm of crescents. It is really weird looking and a lot more interesting than you would think.

neebee

Social climber

calif/texas

May 19, 2012 - 04:31am PT

hey there say, aguacaliente... thanks for the neat share...

ed, thanks for the neat pics!
(awww, and nita... thanks for being so sweet to folks)... :)

did not get to read all these yet...
:))

happy good eve, all..
:)

paganmonkeyboy

climber

mars...it's near nevada...

May 19, 2012 - 10:34am PT

that's no moon...

rolling towards zion in minutes my own self...hang ledge, sit on ledge, drink beverage, watch show...binocs and paper seem the way to go...

Chewybacca

Trad climber

Montana, Whitefish

May 19, 2012 - 12:46pm PT

This topic was discussed on 'Talk of the Nation; Science Friday' yesterday. They recommended a #14 welders glass for safely viewing the eclipse. I've never tried it myself, but if the clouds permit, I will try it tomorrow.

What I'm more interested in seeing is the Venus transit next month. This will not occur again for over 100 years. Hoping for clear skies.

http://www.transitofvenus.org/june2012/where-to-be

Ed Hartouni

Trad climber

Livermore, CA

May 19, 2012 - 03:44pm PT

reading Chewybacca's post and following the links to the NASA site I learned about using the Hα line to view the chromosphere of the sun... I have a Hoya HMC R25A filter, with a spectral transmission of ~0% at <550nm and ~100% at >650 nm, the Hα line is at 656.28nm.

So you can see the sun's chromosphere, in principal... here is a Photoshopped image with the various channels tweaked... showing the result:

50mm + 2x + 1.4x + ND400 + R25A at f5.6 1/8000s ISO 100

here the red channel is very suppressed to be able to "see through" the chromosphere to the photosphere... the filter still lets light through below 550 nm just very suppressed

climbski2

Mountain climber

Anchorage AK, Reno NV

May 19, 2012 - 04:59pm PT

Hmm did you actually catch a couple sunspots there?

Got my eclipse glasses today.. hoping to see the corona fairly well.

neebee

Social climber

calif/texas

May 19, 2012 - 07:01pm PT

hey there say, all... just a bump for tomorrow...

:)

Footloose

Trad climber

Lake Tahoe

May 19, 2012 - 08:45pm PT

Anyone going to try to get the annulus (aka the ring of fire) right at sunset? perhaps in the saddle of some hill or mountain ridge? Where I am it will take place 17 degrees off the horizon (and what is THAT angle called again, I think it has a name?) - that means more than an hour before sunset on the Carson Range summit from which I'll be seeing it.

If so and you got a picture, please post up.

I got my welder shades ready,

Happy viewing!

EDIT

Looks like it's just called "altitude" - duh.

Ed Hartouni

Trad climber

Livermore, CA

May 19, 2012 - 09:01pm PT

possible weather change
cloud cover Sunday evening in Redding and Reno...
the sort of drama I could do without

TGT

Social climber

So Cal

May 19, 2012 - 11:40pm PT

#9 welding glass should be fine.

I've used a #10 (pretty much standard for all but really high current welding)for several previous eclipses. just grabbed the hood and went outside.

The binocular projection method or cardboard box camera obscura gives you a much more detailed and impressive view though.

That would be the ticket for the Transit. Probably wouldn't look like much thru a welding lens.

climbski2

Mountain climber

Anchorage AK, Reno NV

May 20, 2012 - 03:15am PT

Will head towards Fallon or east of Fernley along 395 if necessary

schwortz

Social climber

"close to everything = not at anything", ca

May 20, 2012 - 03:22am PT

i read in multiple locations that only a #14 welding shield/glass is suitable AND that welders glass is NOT additive i.e. 9 + 5 does not = 14. fwiw...i'm not an expert but this info did come from expert sources (nasa, etc)

i bought eclipse glasses - 5 pair for 12 bucks on amazon....

Jon Beck

Trad climber

Oceanside

May 20, 2012 - 03:40am PT

I have viewed them with a Doritos bag. It works. I also use a welding helmet.

Tobia

Social climber

Denial

May 20, 2012 - 06:03am PT

My dad, as a young buck (8-11) suffered life long damage to his vision from viewing an eclipse back in the late twenties or early thirties.

Star gazing, astronomy was a major form of entertainment back then, esp in Merigold, MS where there alternatives were few. It never dulled his appreciation for astronomy, he could name many constellations.

By the time he was in his 70's his vision was very strained and in order to read he had to have a magnifying glass and light source has to be diffused.

Ed Hartouni

Trad climber

Livermore, CA

May 20, 2012 - 12:28pm PT

the eclipse expedition begins...

Chaz

Trad climber

greater Boss Angeles area

May 20, 2012 - 01:32pm PT

We had perfect sky conditions for an eclipse last night. Twenty miles to the west - in Fontana ( where else? ) - there was a forty-foot tall stack of empty wooden pallets on fire. The smoke filtered the setting sun nicely.

If I'm lucky, there'll be something like it again this afternoon.

Good luck, Dr Hartouni!