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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

#171

Post by Stratoscope »

gravypod wrote: post #154
Stratoscope wrote: post #100

Here are my viewing tips, based on my experience in the 1979 eclipse in Oregon. You can photograph the eclipse, but you will have a much grander experience if you don't try. Photography is just a distraction from the awesome spectacle of the eclipse, including the phenomena that happen on the ground. There will be plenty of other people taking great photos, so enjoy those after the eclipse. A total eclipse, viewed di…

> Except during totality, when the Sun's bright face is completely blocked by the Moon, it is never safe to look directly at the Sun through a telescope or binoculars. During the partial phases of the eclipse, you must secure a special-purpose solar filter over the front of your optics before aiming at the Sun. That's a quote from one of the links. Most people will not be in totality. Most people will only be seeing…

Yes, my comment was addressed specifically to those who will be viewing the total eclipse, not the partial eclipse. That's why I emphasized total eclipse and totality.

But thank you for making it more clear that viewing any other kind of eclipse - partial or annular - requires proper eye protection!

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

#172

Post by dionidium »

joezydeco wrote: post #160
dionidium wrote: post #157

Earlier quoted context omitted.

I'll be in St. Louis for this, too. I'm thinking about viewing it from here: https://mostateparks.com/event/64121/solar-eclipse-showdown

I've been trying to scout out some open areas away from civilization, mostly to avoid ambient light but also to avoid huge traffic in and out of any park or freeway interchange. I fully anticipate traffic to be screwed up for hours afterward.

I could be totally wrong, but I just don't see it, at least not down there in Jefferson County. That's not a densely populated area. It's over an hour's drive from Downtown St. Louis. [0]

I have to say, though, I'll probably leave earlier that morning than I'd originally planned, because of the comments in this thread.

[0] https://goo.gl/maps/bJRKJndLnQG2

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

#173

Post by BenjiWiebe »

JPKab wrote: post #158
ant6n wrote: post #101

Earlier quoted context omitted.

I'm planning to drive up north from Denver, the day of. Kind of concerned about how many people will have the same idea, and how early I should start...

I'm in Denver area too. The question is this: How much better is a 100% eclipse vs. a 90% eclipse that we'll get here? Is it worth the trip to Wyoming? I think so, but not positive.

According to everything I've read, and all pictures I've seen, 99% is one thing, and 100% totally something else.

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

#174

Post by oh_sigh »

leblancfg wrote: post #43
dekhn wrote: post #12

Earlier quoted context omitted.

it's projection geometry. You create a geometry object with the earth's surface shape. Another with the moon's surface shape. Then, a light source that emits from a sun's shape. All objects are placed at the appropriate distances, and made to rotate and translate through space according to normal orbits. Then, you project the light from the sun onto the earth, with the moon in-between. This creates the 2D shape on th…

Thanks dehhn. From the LRO picture in the article, you can see that they're actually taking high-precision elevation maps of both the Moon and Earth into consideration, which sounds like something rather computationally intensive. I might be wrong, but I don't think they used Blender to handle that. I would be curious to hear what tool they actually use, their pipeline, etc.

Depends how high precision those maps are, but I can't imagine it being a very big deal with the right data pruning(you only need to consider elevations near wear earth intersecting sun rays are close to tangential to the moons surface)

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

#175

Post by tropo »

bhandziuk wrote: post #83
BatFastard wrote: post #81

Why would they use a tif format for the downloadable map? I haven't seen a tif format in 10 years.

lossless format (potentially) that everyone can open?

Nope. This is in fact why TIFF is pretty much dead.

The format is very extensible. It was originally specified to have 5 ways to encode data: uncompressed, LZW, fax, RLE, and JPEG. The use of proprietary encodings is normal however, along with several non-proprietary encodings. Data can be lossless or not. Data can be bitmap or vector. There are even two different ways to store JPEG data, with many tools supporting only the original style and many other tools only supporting the newer style.

Now consider trying to view a TIFF that you have received. You have a several TIFF-capable image viewers. No two of them handle the same set of encodings. The most recently installed viewer is associated with the file extension, and as a normal user you are thus unable to use the other viewers. If you install another TIFF-capable viewer, you gain the ability to view some TIFF images while losing the ability to view some other images.

PNG just works. JFIF and EXIF JPEG do too, because nobody creates 12-bit or arithmetic-encoded files. GIF just works.

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

#176

Post by Grangar »

baursak wrote: post #51
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…

> Watching the sun get eaten by a black void activates something deep inside the animal brain. I was planning to have my 5 year old son see it. But now I wonder whether it will have any traumatic effect on him.

It was my 6th birthday when I saw it. I still vividly remember it, in a good way.
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