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Bonez
12-04-07, 21:50
I don't really know what to research, since I don't know if it has a word, but I have a question about light and dark.

Well, obviously the world is round, and one half is in light and one half in darkness. ( Not perfectly I don't think though... )

Anyway... What if you lived on the exact line of light and dark?

Would it be night all the time.. or day all the time?

Or could you go outside and see a wall of dark? I'm being serious. :p

Mad Tony
12-04-07, 21:53
There isn't a line that separates the two. It just gets gradually darker/lighter as you move around. Then back again.

Lew
12-04-07, 21:54
Also, the earth titles on its axsis during summer and winter, thats why Australia has different winter than us, when we have our summer.

Bonez
12-04-07, 21:55
Oh ok.. But i still don't understand.

Ok.. if you were flying somewhere, and it would be night when you arrived but day when you set off... would you enter a wall of darkness?

Lew
12-04-07, 21:56
It would probably get gradually darker like sunset. I dunno

Ampersand
12-04-07, 21:56
I imagine it fades gradually from one to the other. It's not like someone actually gets a ruler to draw where the sunlight stops. :D

Bonez
12-04-07, 21:57
It's not like someone actually gets a ruler to draw where the sunlight stops. :D

Thats how I imagine it XD

Oh ok, thanks. I forget about the tilting axis...

walk_man
12-04-07, 22:01
Yeh, you can never stand on a line. Tho, when the sun is setting, look at the sun area, then look behind you. Sometimes it looks like Night.

Geck-o-Lizard
12-04-07, 22:02
You've never seen a sunset?

Bonez
12-04-07, 22:06
Me? Yeah..

Geck-o-Lizard
12-04-07, 22:22
That's what the boundary between night and day looks like. No wall of darkness. :)

Punaxe
13-04-07, 00:18
Exactly. If there would indeed be a wall of darkness or a sharp line, you would see this wall or line approach every evening, and it will be dark within a second after passing it.
Instead, we see a gradual decrease of light intensity. If you spread this out over an axis of time, it is actually the same as it is spread over the Earth.

Izzie404
13-04-07, 00:22
That would be so cool...but kind of ominous looking. So...when you are flying, you're going really fast thru time? :jmp::jmp:

Ok, now I have a question: If you were to go all the way around the world [so go through all the time zones] before one day had passed, would you go back in time :confused:

Mr.Burns
13-04-07, 00:30
That would be so cool...but kind of ominous looking. So...when you are flying, you're going really fast thru time? :jmp::jmp:

Ok, now I have a question: If you were to go all the way around the world [so go through all the time zones] before one day had passed, would you go back in time :confused:


No. Time is constant. Going by your question, even though according to our clocks and calenders you may (or may not, I'm not sure) have gone one day ahead or stayed the same, your passage through time has remained constant. While it is theoretically (highly debatable) possible to travel back in time, it is impossible with our current level of technology and based on the study released (I'll see if I can dig it up for you) it would be highly impractical.

EDIT: Here ya go (http://www.time.com/time/magazine/article/0,9171,996610-1,00.html). :wve: It's not the actual one I'm looking for but this should help.

Einstein's Theory of Relativity states that the closer to the speed of light one travels, the slower through time we would proceed so if we somehow managed to get that close in speed, a few days for us would be in reality a few months or years.

Tomb-Raider
13-04-07, 01:03
this is very confusing..

Ward Dragon
13-04-07, 05:28
I don't really know what to research, since I don't know if it has a word, but I have a question about light and dark.

Well, obviously the world is round, and one half is in light and one half in darkness. ( Not perfectly I don't think though... )

Anyway... What if you lived on the exact line of light and dark?

Would it be night all the time.. or day all the time?

Or could you go outside and see a wall of dark? I'm being serious. :p

This might help you to visualize it. Take a globe into a dark room (or a ball if you don't have a globe). Shine a flashlight directly at the side of the globe to represent the sunlight. If you spin the globe, you should notice that a particular point, say a city, will gradually get lighter and darker as it goes through the "day."

This little movie might help you to visualize how the amount of sunlight changes during a year as the earth moves in relation to the sun. This causes the different seasons. For example, when the earth is in a position where the northern hemisphere receives the most light due to the tilt of the axis, then it is summer in the northern hemisphere and winter in the southern hemisphere.

http://www.classzone.com/books/earth_science/terc/content/visualizations/es0408/es0408page01.cfm?chapter_no=04

I hope this helps :) If it doesn't make any sense, that's because I drank a bottle of Vault and now I have insomnia despite being tired :rolleyes:

Mytly
13-04-07, 05:55
I don't really know what to research, since I don't know if it has a word, but I have a question about light and dark.

Well, obviously the world is round, and one half is in light and one half in darkness. ( Not perfectly I don't think though... )

Anyway... What if you lived on the exact line of light and dark?

Would it be night all the time.. or day all the time?

Or could you go outside and see a wall of dark? I'm being serious. :p
As Geck-o-Lizard points out, the boundary between night and day looks exactly like sunset or sunrise (indeed, that's precisely what sunset and sunrise are!).
But this applies only to a planet like Earth which has an atmosphere, which causes the sun's light to scatter. On airless worlds like the Moon, there is a sharp distinction between night and day, and even between shadows and light. But even there there is no such thing as a "wall of dark", as one cannot see darkness.

Bonez
13-04-07, 11:22
Oooh.. thanks so much everyone. :)

Time is really wierd.

Andromeda66
13-04-07, 11:28
You'll appreciate Einstein theory of Relativity and Time Dilation better a bit later in school or college. :wve:

If you are really interested, however, I would recommend you read 'The Universe In A Nutshell' by Stephen Hawking. It explains time travel in simple, elegant words. :)

Bonez
13-04-07, 11:44
You'll appreciate Einstein theory of Relativity and Time Dilation better a bit later in school or college. :wve:

If you are really interested, however, I would recommend you read 'The Universe In A Nutshell' by Stephen Hawking. It explains time travel in simple, elegant words. :)

Cool! I mighthave to check that out... its very interesting. :)

Mr.Burns
13-04-07, 16:53
There's also a "Brief History of Time." Hawking's most famous book. A bit more technical than "Nutshell" but still a good read:)

Andromeda66
14-04-07, 12:04
Yes. That book gives me the impression that he enjoys being deliberately obscure at times.