Astronomy & Space - October 2006

In trying to use a GPS receiver to determine "sunrise", the answer given was not what I want. I need to determine the time at which early morning twilight begins (eg. still totally dark) when all I have is the time of sunrise.
Given the variables of :elevation on the earth , level surrounding terrain, time of the season, etc...What is the number of minutes I subtract from "sunrise", as given by a GPS unit, to arrive at that time at which early morning twilight will begin (but is still completely dark)?

2006-10-12 08:33:03 · 4 answers · asked by Jim B 1

2006-10-12 08:22:09 · 11 answers · asked by Abdul Karim 1

How many days lapse and how far does it travel in 1 orbit around the Sun?

2006-10-12 07:38:15 · 28 answers · asked by exert-7 7

2006-10-12 07:32:20 · 16 answers · asked by Andy C 1

Sometimes in the early night hours as the moon appears over the horizon the moon looks huge but as it moves overhead in the sky its apparent size gets much smaller. I would think that the moon at the horizon is further away from me than when its directly above.

2006-10-12 07:30:56 · 9 answers · asked by abel g 2

2006-10-12 07:26:35 · 6 answers · asked by Rachit 1

2006-10-12 07:25:07 · 2 answers · asked by Rachit 1

2006-10-12 07:18:21 · 3 answers · asked by Anonymous

2006-10-12 06:11:38 · 5 answers · asked by aladin 1

2006-10-12 06:10:10 · 8 answers · asked by Lisa 1

rotation of the moon how fast in miles per hour does it rotate

2006-10-12 05:55:16 · 6 answers · asked by jan 1

If not, what was "there" before the big bang?

2006-10-12 05:08:01 · 21 answers · asked by Wing commander 3

2006-10-12 05:02:53 · 20 answers · asked by Trueblue 1

what would happen if it suddenly stopped?

2006-10-12 05:01:10 · 13 answers · asked by daka 2

2006-10-12 04:49:20 · 8 answers · asked by Lisa 1

2006-10-12 04:47:45 · 5 answers · asked by Lisa 1

about the moon

2006-10-12 04:02:24 · 5 answers · asked by jan 1

2006-10-12 04:01:47 · 17 answers · asked by mumphie 1

Can ne1 launch their own satellite or do they need permission from the countries it would orbit over or the country it would be launched from? Do government people check them out before they can be launched? Are satellites allocated their own space outside our atmosphere so they don't all crash into each other?

2006-10-12 03:11:35 · 9 answers · asked by Anonymous

2006-10-12 02:59:44 · 7 answers · asked by Anonymous

how far away is it. or how long will it take to reach there with current technology?

2006-10-12 02:55:00 · 7 answers · asked by Anonymous

2006-10-12 02:35:58 · 1 answers · asked by STORMY K 3

2006-10-12 02:29:19 · 3 answers · asked by STORMY K 3

i read in a book that the denssity of a black hole is 100000000000000000000000000000000000000000000000000000000000000000000000000000000 tons per cubic in. of 1E^80 tons per cubic in. is it true? i thought that you could not mesure that because nothing could get close enough to test it without being destroyed.

2006-10-12 02:05:41 · 9 answers · asked by fayt 2

Here are some surface pictures of Venus for those of you who didn't know they existed.http://www.mentallandscape.com/V_DigitalImages.htm

2006-10-12 01:58:43 · 10 answers · asked by Anonymous

what do scentists predict?

2006-10-12 01:52:53 · 24 answers · asked by ? 1

2006-10-12 01:41:36 · 9 answers · asked by meenal 1

2006-10-12 01:32:28 · 5 answers · asked by BRIAN M 1

Is there any theories regarding this?

2006-10-12 01:21:30 · 22 answers · asked by ? 1

2006-10-12 01:16:23 · 22 answers · asked by Anonymous