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What did Earth look like X million years ago?

dinosaurpictures.org

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Re: What did Earth look like X million years ago?

#61

Post by TeMPOraL »

jamesrcole wrote: post #25

That's pretty cool. I have two suggestions, if the developer is seeing this: - Mark the North and South poles. For someone unfamiliar with the past continental layouts, it's easy to get a bit disoriented . I would find a location on the globe, jump back in time, rotate the globe a bit to look around, then jump further back in time and then start to get disoriented as to where on earth the details I'm looking at are.…

> - Mark the North and South poles.

I find it easy to tell where the poles are - that's where the cloud texture gets visibly broken :).

Re: What did Earth look like X million years ago?

#62

Post by illwrks »

Brilliant, although it would be excellent if the transitions between the times was animation.

Perhaps the time could be represented as a video. Draw a video frame to a canvas and use as a texture for the sphere. As the time is updated just play forward or backward to a video point and the texture would update.

Re: What did Earth look like X million years ago?

#63

Post by chimprich »

JumpCrisscross wrote: post #7

Has anyone made a large-format map (or better yet: globe) across which one can scroll to past geographic and political maps?

Here's one: http://geacron.com I'm sure I saw another one recently with a better GUI but I can't seem to find it again.

Re: What did Earth look like X million years ago?

#65

Post by Steuard »

JumpCrisscross wrote: post #7

Has anyone made a large-format map (or better yet: globe) across which one can scroll to past geographic and political maps?

I think so! The "Magic Planet" is a digital projection globe that can display all sorts of different datasets. I've been more interested in its planetary science, astronomy, and geology applications, but I believe they've got lots of political, cultural, and economic visualizations as well.

http://globalimagination.com/

Re: What did Earth look like X million years ago?

#66

Post by gus_massa »

dluan wrote: post #17

Last week I was in the field digging dinosaurs in Montana, when one of the dig leaders mentioned there was no grass back then, just lots of ferns, because grass hadn't evolved yet. It kind of blew my mind that for most of dinosaurs, there was just a lot of leafs and ferns. Here's some pictures for context ( https://imgur.com/a/rE5wwc4 ), when you're out where most dino bones are found, you forget that it may have bee…

Do you have a blog post with more photos/context? It can be an interesting submission, specially if you can answer the comments.

Re: What did Earth look like X million years ago?

#67

Post by gus_massa »

perl4ever wrote: post #32
jcims wrote: post #29

Earlier quoted context omitted.

It is my understanding that you can mitigate this to an extent by making larger scopes or employing techniques like interferometry. I haven't found an absolute 'hard limit', only a limit based on the size of the resolving device. I'm generally a moron in this area though so I'm certainly missing large swaths of information.

On the other hand, earth is a finite sized object, and so are photons, so there are only so many photons to work with no matter how large your detector.

[I agree.]

I'm too lazy to try the calculations now, but if the nearest black hole is 2800 ly away, I guess the size of lens to resolve a dinosaur have to be much bigger than the solar system. Probably a few light-year [calculation needed]. Does the lens reach Proxima Centaury? Does the lens collapse and form another black hole?

Also, the black holes are big, but they are more far away than big, so the angular size of the area that does some interesting lens effect is very small. Then even if you have a giant lens and collect all the light that the black hole has blended (more than 90° or something), you will get a extremely dim image. But photons are discrete, and visible photons have a minimal energy, so the image will be composed of a very small amount of dots, and not something smooth where you can see anything.

Re: What did Earth look like X million years ago?

#70

Post by rement »

weinzierl wrote: post #53
barking wrote: post #52

Topically, I see Britain had everything sorted 150 million years ago while the rest of Europe was in a right heap.

First thing I noticed as well. Joking aside: Any ideas why this is so? It's not that the British Islands elevation is so extreme.

The British Isles are away from the plate edges where most disruptive geologic activity occurs (earthquakes, volcanoes, subduction, etc). The rest of Europe is along the edges of the plate and was geologically active. If you look at North West Brazil you can see very little happens for over 240 million years (away from plate edge) while Oceania has been very active for the last 100+ million years (and is still very active).

If you look at the ocean while you go back in time you can see large swaths that have very little detail. This is because that rock has been geologically recycled and is no longer part of the geologic record.

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