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View Full Version : Can we recognize east west south and north in space at night?



suntrack2
2006-Sep-07, 11:49 AM
If I am in space and doing journey in night how can I recognize the east,west,south and north when I have no instrument to recognize at which position I am going.


sunil

Tog
2006-Sep-07, 12:04 PM
If I am in space and doing journey in night how can I recognize the east,west,south and north when I have no instrument to recognize at which position I am going.


sunil

You can't. There is no "north" in space. North is casued by the magetic poles on a planet. In space you need to use the stars. If you set a bright, distant star, like Deneb, as "north", you could use that for all of you navigation. If Deneb is 20 degrees to your left and "above" your line of flight, you would have some idea where you were going. The further the star is, the more accurate this will be, since as you get close, you will run into an error as the star's position shifts. Better yet would be another galaxy, as long as you could see it clearly.

Oh, and there should be a star about 90 degrees from the one you use as north. This one would be "up". You would use it to make sure you are still "level". A 5 degree tip of the wings to the right could end up making a huge navigation error.

For travel in just our solar system, any star will do. None of the bright ones are close enough to make much of a difference.

That's my take. See below for corrections.:p

NEOWatcher
2006-Sep-07, 04:10 PM
That's my take. See below for corrections.:p
My take too. So no correction.

But; I would like to add there is no "night" in space unless you are behind something.

captain swoop
2006-Sep-07, 04:38 PM
well eventhat depends how close to the sun your are

Bob
2006-Sep-07, 04:52 PM
You are always east of the sun and west of the moon.

SMEaton
2006-Sep-07, 05:03 PM
Galactic coordinates, possibly?

tofu
2006-Sep-07, 05:52 PM
Well, you can always find polaris (the north star) so you call that North, and South would be opposite of that. We could come up with a similar rule for East/West.

Very far outside of our solar system though, that system would break down. It'd be better to use a quasar instead of a star, then you could have cardinal directions from anywhere in our galaxy.

hhEb09'1
2006-Sep-07, 09:31 PM
Here's an exercise to try. Imagine that you're on the earth, and you look straight up, and there is a star above you. If you head straight up for that star, you are not going east nor west nor south nor north.

But in space you'd always be heading towards some star that was directly over some point on earth.

To find direction, use a galactic coordinates map, as SMEaton suggested.