Big stuff, far away, what does it look like? [Archive] - Wizards Community

Big stuff, far away, what does it look like? [Archive] - Wizards Community

Post/Author/DateTime Post
Zebek
09-11-05, 07:26 PM I'm designing my campaign world at the moment and have decided to use a weird shape which means I need to put some thought into the physics.
One current problem is what would a 50 mile high rock wall look like to someone on a flat world? How far away can you be before the atmosphere makes such a feature too fuzzy to make out? 100 miles?
Maybe only the base would be fuzzy but the top clearer due to the relatively thinner layer of atmosphere in between at that angle.
Maybe I should be logging on to a weather forum :confused:
Seeker95
09-11-05, 11:25 PM You can see 20 miles on a clear day even on our curved planet. From Alaska you can see the eastern coastline of Siberia.

On a flat planet, I would assume you can see close to forever, depending on the atmosphere. After all, I can see the moon pretty clear without a telescope. How much detail you can see at what distance would probably have more to do with the quality of your eyes than the size of the object you're looking at.

A 50 mile high rock? You could easily see it from a couple hundred miles away. (On a clear day)
buggritall
09-12-05, 12:28 AM A fifty mile high rock on a flat world is probably impossble to miss, anywhere. Bear in mind that at only 6 miles, you're already in space. 50 miles high is insane.
fukachu
09-12-05, 12:54 AM On the plus side you don't need to work out anything but how far they are from the rock wall, as they won't be able to see past it. Look up some stuff on light, perspective and relative refraction. On the less physics more game side, a towering wall in the sky above the clouds would be awesomely ominous especially if foreground clutter obscured the base.
Solaris
09-12-05, 01:31 AM According to http://en.wikipedia.org/wiki/Eye, the human eye can resolve distances of about 0.73 millimeters at a distance of one meter.

That means you could discern a fifty mile high object at a distance of about 68493 miles.

An atmosphere absorbs and scatters light, however, so you wouldn't get anything like that kind of visibility. Seeker said 20 miles on a clear day -- it could be much less on another day.

Also, remember that the top will be farther away from a ground-based observer than the bottom. So even with 20 miles of visibility an observer 10 miles away from the wall will only be able to see a bit more than 17 miles up it.

Then there's depth of atmosphere to worry about too, as someone else pointed out...
Zebek
09-12-05, 07:13 AM After all, I can see the moon pretty clear without a telescope. Sure, but that's just a smear of atmosphere in the way compared to seeing across the Earth surface.
Also, remember that the top will be farther away from a ground-based observer than the bottom. So even with 20 miles of visibility an observer 10 miles away from the wall will only be able to see a bit more than 17 miles up it.You will get the same "seeing the moon" situation here. If you are 10 miles away from the base then that's 10 miles of dense atmosphere to get through to see the bottom; looking up 80 degrees at the top of the wall, though, will involve a lot less dense atmosphere in the way (assuming Earth-type atmosphere).
50 miles high is insane.Actually it's just a step :)
Imagine flat rectangular slabs, each the size of Wyoming, in a set of stairs. On one side a step up of 50 miles and on the opposite side a step down of 50 miles. Or everything several times bigger than that as 100,000 square miles isn't going to support a lot of civilisation. I haven't decided on exact scale yet.
On the less physics more game side, a towering wall in the sky above the clouds would be awesomely ominous especially if foreground clutter obscured the base.I was thinking that would be OK as it would have always been there. Of course, the folklore creationist stories for The Wall (and, of course, The Drop) would vary on distance. Those "in the shadow" may just be waiting for it to fall on them whilst those in the distance just think the "wall above the clouds" is "very big".
Joe Khol
09-12-05, 12:29 PM I'd suggest making it look however you want to and keep the physics explanation fuzzy.

Unless the player characters are due to gain some deep scientific understanding of the campaign world you can get away with 'It just is!'.

Post/Author/DateTime	Post
Zebek 09-11-05, 07:26 PM	I'm designing my campaign world at the moment and have decided to use a weird shape which means I need to put some thought into the physics. One current problem is what would a 50 mile high rock wall look like to someone on a flat world? How far away can you be before the atmosphere makes such a feature too fuzzy to make out? 100 miles? Maybe only the base would be fuzzy but the top clearer due to the relatively thinner layer of atmosphere in between at that angle. Maybe I should be logging on to a weather forum :confused:
Seeker95 09-11-05, 11:25 PM	You can see 20 miles on a clear day even on our curved planet. From Alaska you can see the eastern coastline of Siberia. On a flat planet, I would assume you can see close to forever, depending on the atmosphere. After all, I can see the moon pretty clear without a telescope. How much detail you can see at what distance would probably have more to do with the quality of your eyes than the size of the object you're looking at. A 50 mile high rock? You could easily see it from a couple hundred miles away. (On a clear day)
buggritall 09-12-05, 12:28 AM	A fifty mile high rock on a flat world is probably impossble to miss, anywhere. Bear in mind that at only 6 miles, you're already in space. 50 miles high is insane.
fukachu 09-12-05, 12:54 AM	On the plus side you don't need to work out anything but how far they are from the rock wall, as they won't be able to see past it. Look up some stuff on light, perspective and relative refraction. On the less physics more game side, a towering wall in the sky above the clouds would be awesomely ominous especially if foreground clutter obscured the base.
Solaris 09-12-05, 01:31 AM	According to http://en.wikipedia.org/wiki/Eye, the human eye can resolve distances of about 0.73 millimeters at a distance of one meter. That means you could discern a fifty mile high object at a distance of about 68493 miles. An atmosphere absorbs and scatters light, however, so you wouldn't get anything like that kind of visibility. Seeker said 20 miles on a clear day -- it could be much less on another day. Also, remember that the top will be farther away from a ground-based observer than the bottom. So even with 20 miles of visibility an observer 10 miles away from the wall will only be able to see a bit more than 17 miles up it. Then there's depth of atmosphere to worry about too, as someone else pointed out...
Zebek 09-12-05, 07:13 AM	After all, I can see the moon pretty clear without a telescope. Sure, but that's just a smear of atmosphere in the way compared to seeing across the Earth surface. Also, remember that the top will be farther away from a ground-based observer than the bottom. So even with 20 miles of visibility an observer 10 miles away from the wall will only be able to see a bit more than 17 miles up it.You will get the same "seeing the moon" situation here. If you are 10 miles away from the base then that's 10 miles of dense atmosphere to get through to see the bottom; looking up 80 degrees at the top of the wall, though, will involve a lot less dense atmosphere in the way (assuming Earth-type atmosphere). 50 miles high is insane.Actually it's just a step :) Imagine flat rectangular slabs, each the size of Wyoming, in a set of stairs. On one side a step up of 50 miles and on the opposite side a step down of 50 miles. Or everything several times bigger than that as 100,000 square miles isn't going to support a lot of civilisation. I haven't decided on exact scale yet. On the less physics more game side, a towering wall in the sky above the clouds would be awesomely ominous especially if foreground clutter obscured the base.I was thinking that would be OK as it would have always been there. Of course, the folklore creationist stories for The Wall (and, of course, The Drop) would vary on distance. Those "in the shadow" may just be waiting for it to fall on them whilst those in the distance just think the "wall above the clouds" is "very big".
Joe Khol 09-12-05, 12:29 PM	I'd suggest making it look however you want to and keep the physics explanation fuzzy. Unless the player characters are due to gain some deep scientific understanding of the campaign world you can get away with 'It just is!'.