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The most accurate map for August 21’s total solar eclipse

nasaviz.gsfc.nasa.gov

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Re: The most accurate map for August 21’s total solar eclipse

#61

Post by learc83 »

Florin_Andrei wrote: post #26
learc83 wrote: post #13

Earlier quoted context omitted.

I don't see the point of booking something without knowing the weather unless you don't care about throwing it away and going somewhere else. My initial plan was to book several hotels in different areas, but it seems like every hotel inside the path of totality requires a 2 week notice to cancel (and this was months ago). Since I'm about 1.5 hours from the path of totality in Georgia, my current plan is to drive out…

Book it months in advance, and then the price is normal. That's what I did. I'll be in Salem.

But you're still out the money in case of heavy cloud cover.

And I don't trust people not to cancel early bookings once they realize what kind of prices they can get.

Re: The most accurate map for August 21’s total solar eclipse

#62

Post by Angostura »

idlewords wrote: post #24

If you've never seen a total eclipse before and you live in the US, make every effort to see this one! It's not something that you can get the feel of by viewing photos or video. Watching the sun get eaten by a black void activates something deep inside the animal brain. Don't settle for a partial eclipse, do what it takes to get in the path of totality. If you have seen a total eclipse before, then you don't need an…

I'd recommend finding somewhere near leafy forest if you can. Watching the dappled shade gradually become thousands of tiny crescents is really interesting. I'd never realised that the canopy created multiple pinhole-camera images of the sun until then.

Re: The most accurate map for August 21’s total solar eclipse

#63

Post by hellbanner »

idlewords wrote: post #24

If you've never seen a total eclipse before and you live in the US, make every effort to see this one! It's not something that you can get the feel of by viewing photos or video. Watching the sun get eaten by a black void activates something deep inside the animal brain. Don't settle for a partial eclipse, do what it takes to get in the path of totality. If you have seen a total eclipse before, then you don't need an…

Is that the "Black circle"? Or is that the line of the path?

Re: The most accurate map for August 21’s total solar eclipse

#64

Post by aakriti1215 »

jasode wrote: post #15
JPKab wrote: post #8

Earlier quoted context omitted.

I think Oregon is a bad spot to view it. The weather (yes, even in summer) is too unpredictable and it's too close to populated coastal areas. Wyoming is the way to go, or western Nebraska. Don't expect to get hotels, but camping on a rancher's land is easy, and the arid climate in the summer minimizes chances of cloud cover.

>, or western Nebraska. I'll be in eastern Nebraska (Omaha) and will drive south on I-80 towards the eclipse path and hopefully pull off to the side and park somewhere. What's hard to plan for is whether too many other Nebraskans will have the exact same idea which means I have to camp out a ridiculous 12 hours before the event to secure a spot -- or give up entirely.

I'm in Lincoln and I don't think too many people are planning to go far since its in the middle of the day.

Re: The most accurate map for August 21’s total solar eclipse

#65

Post by jessriedel »

Dave_Rosenthal wrote: post #41
jessriedel wrote: post #32

Can someone explain why the claimed shadow of the moon is vastly more bumpy than it ever appears in the night sky? Or how to square this with the fact that altitude of the highest and lowest points on the Moon differ by less than 20km, or less than 1% of the diameter? The shadow looks like it has bumps of about 5-10% of the diameter.

The diameter of the path of totality is only about 100 miles, because it's only the umbra of the shadow. This is 20x smaller than the moon diameter. But, a 1km moon bump is a 1km bump on the umbra as well, magnifying it's effect by the mentioned 20x and leading to a much different appearance.

I hadn't thought about this effect! You're absolutely right. Thanks very much.

(For others:) A diagram of the umbra makes this clear:

https://c.tadst.com/gfx/750x500/total-solar-eclipse-com.png?...

If you draw a few triangles, you can get an analytic expression.

Re: The most accurate map for August 21’s total solar eclipse

#66

Post by frandroid »

hellbanner wrote: post #59
rbritton wrote: post #4

Some tips for photographing it: http://www.nikonusa.com/en/learn-and-explore/a/tips-and-tech... Solar filters: https://www.bhphotovideo.com/c/buy/solar-photography-filters...

Won't it just be.. black?

http://cdn-7.nikon-cdn.com/Images/Learn-Explore/Photography-...

Re: The most accurate map for August 21’s total solar eclipse

#67

Post by Symbiote »

hellbanner wrote: post #60

Are these safe to view? I thought these would be black. Another link talks about "getting eye protection"?

Eye protection is essential.

There was a total eclipse in Britain when I was a child [1], and everyone bought special protective glasses to wear.

Mine were like the paper red-green "3d" glasses you used to get, but with a black film that was close to opaque. They worked fine.

[1] http://xjubier.free.fr/en/site_pages/solar_eclipses/TSE_1999... ("Britain" is exaggerating, but we were in Cornwall on holiday.)

Re: The most accurate map for August 21’s total solar eclipse

#68

Post by scott_s »

hellbanner wrote: post #59
rbritton wrote: post #4

Some tips for photographing it: http://www.nikonusa.com/en/learn-and-explore/a/tips-and-tech... Solar filters: https://www.bhphotovideo.com/c/buy/solar-photography-filters...

Won't it just be.. black?

See ErrantAstro's excellent post in this thread, the "second factor": https://news.ycombinator.com/item?id=14547178

Re: The most accurate map for August 21’s total solar eclipse

#69

Post by scott_s »

ErrantAstro wrote: post #40
jessriedel wrote: post #32

Can someone explain why the claimed shadow of the moon is vastly more bumpy than it ever appears in the night sky? Or how to square this with the fact that altitude of the highest and lowest points on the Moon differ by less than 20km, or less than 1% of the diameter? The shadow looks like it has bumps of about 5-10% of the diameter.

There are two principal factors at work here. The first is the eccentricity of the lunar orbit - 0.0549 which means that depending on where in the lunar orbit the eclipse occurs, the moon is closer or further away meaning the apparent size ratio between the Sun and Moon varies. In fact - it's even possible to have an eclipse where the Sun's limb is visible around the edge of the Moon at totality - this is called an a…

To anyone who viewed the YouTube link above, reference [2], go back to about 2:45 and watch the start of the diamond ring effect. It's spectacular.

Re: The most accurate map for August 21’s total solar eclipse

#70

Post by jen729w »

wyldfire wrote: post #2

I heard from a co-worker who plans to travel to Oregon that some of the hotel rooms in the path of the umbra are sometimes > 2-3k USD for the night(s) prior to the eclipse.

We're travelling all the way from Australia for this (thanks to my epic girlfriend). Got a roadside motel in Pleasant View, ~50 miles from maximum totality (Hopkinsville), for Not expecting it to be anything flash, but there's stuff out there. Don't be put off!
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