Page 1 of 2

Navigating with the moon and a watch

PostPosted: Mon Sep 19, 2011 6:33 pm
by machineman9
This has sparked off because a friend of mine has become lost in country lanes just minutes off from where they're meant to be heading (though, she is the sort who would get lost on a straight road). So I thought...

If you can use your wristwatch to navigate with the sun (in the Northern hemisphere, align hour hand with sun and bisect the angle between that and '12' to find North/South line, then use common sense to work out which side is East and which is West) can you do it with the moon?

Would it follow the same guideline for the moon? It is quite late, so the sun has gone to bed... And England being England, it is constantly covered in cloud (so no stars to follow!)


Cheers

Re: Navigating with the moon and a watch

PostPosted: Mon Sep 19, 2011 6:52 pm
by Club508
I don't know for certain, But I'm pretty sure you can't.  The reasons I think that are:
1.  The moon is orbiting around us as we spin on our axis, the sun is staying in the same place RELATIVE TO OUR SOLAR SYSTEM.
2.  The moon deviates within about 10* up and down in it's orbit around us.

Re: Navigating with the moon and a watch

PostPosted: Mon Sep 19, 2011 7:27 pm
by machineman9
That is very true, and both are reasons I had considered. It's hard to keep complete track of that celestial body, but it seemed to show up in quite a similar location most nights at the same time. A wobbly orbit, yeah, but hopefully good enough to determine all 4 directions?

Re: Navigating with the moon and a watch

PostPosted: Mon Sep 19, 2011 7:40 pm
by Webb
Wouldn't it be easier to just find the north star?

Re: Navigating with the moon and a watch

PostPosted: Mon Sep 19, 2011 7:44 pm
by hyperpep111
That's a tricky one.
I'm not an astronomer so I'm not very good at this. But here's what I know...
The full moon rises to the east So at midnight it's approximately to the south and sets in the west because of it's orbit course.
If it's a crescent moon you can Imagine a line from tip to tip of the crescent which when It touches the horizon It's approximately south.
I don't understand it either. So it's up to you to guess where North or South Is :o.
And Your friend drives without a compass or any navigational data including gps a map? :-X

Re: Navigating with the moon and a watch

PostPosted: Mon Sep 19, 2011 7:51 pm
by beaky
Despite its motion relative to the Earth, the Moon rises and sets at roughly the same interval as the Sun. So the watch thing might work. But it may rise during the day, or have set by sundown... not much use in using the moon when ol' Sol is visible.

Re: Navigating with the moon and a watch

PostPosted: Tue Sep 20, 2011 9:03 am
by ozzy72
Depending on the time of the month you can use this method (you have to know if the moon is waxing or waning).

Because the moon has no light of its own, we can only see it when it reflects the sun's light. As it orbits the earth on its 28-day circuit, the shape of the reflected light varies according to its position. We say there is a new moon or no moon when it is on the opposite side of the earth from the sun. Then, as it moves away from the earth's shadow, it begins to reflect light from its right side and waxes to become a full moon before waning, or losing shape, to appear as a sliver on the left side. You can use this information to identify direction.

If the moon rises before the sun has set, the illuminated side will be the west. If the moon rises after midnight, the illuminated side will be the east. This obvious discovery provides us with a rough east-west reference during the night.

It isn't good enough for putting a bomb through a terrorists front door but it can get you pointed in the right direction.
One of my Kiwi mates had an abillity to navigate using this and the time and could actually get you on a course within a couple of degrees of a compass reading! I never got that good at it.

Re: Navigating with the moon and a watch

PostPosted: Tue Sep 20, 2011 9:27 am
by jetprop
just saying but if you have a  watch and you can see the moon,why dont you check the time and see where the moon is?
if its midnight,well,then you might have a problem.

Re: Navigating with the moon and a watch

PostPosted: Tue Sep 20, 2011 10:09 am
by DaveSims
The problem is the moon is not always in the same location at the same time.  Sometimes it is up during the day, sometimes it is up at night.  I would think navigating by the moon would be more like navigating by the stars, needing a book that would give locations for a given date/time. 

Re: Navigating with the moon and a watch

PostPosted: Tue Sep 20, 2011 1:00 pm
by H
If only using the Moon, rising in the east and setting in the west, as a 'general' direction indicator when one is substantially north or south of the equatorial line, that isn't a major problem. The query concerned direction, so let's not confuse time with directional reference, the two only definitively relitively important for something more exact... and, obviously, the Moon could only be used as a reference when it's there... it's always nice to have at least a dim view of where you're going.
;)


8-)

Re: Navigating with the moon and a watch

PostPosted: Tue Sep 20, 2011 3:26 pm
by Club508
I think I have a good idea,
Just get out and ask for directions! :D

If you ask me, it's more manly to ask for directions and make it home than to run out of fuel and be completely helpless. ::)
And even then you'll  still need to ask for directions anyway.

Re: Navigating with the moon and a watch

PostPosted: Tue Sep 20, 2011 4:27 pm
by hyperpep111
Club. It's in the middle of the night. You aren't just gonna get out and ask for directions. Maybe thieves, Murderers e.t.c are out there :o

If you ask me, it's [glow=yellow,2,300]more manly [/glow]to ask for directions and make it home than to run out of fuel and be completely helpless.


This has sparked off because a friend of mine has become lost in country lanes just minutes off from where they're meant to be heading (though, [glow=yellow,2,300]she[/glow] is the sort who would get lost on a straight road). So I thought...


Just to clarify ::)

Re: Navigating with the moon and a watch

PostPosted: Tue Sep 20, 2011 5:52 pm
by machineman9
To be fair, I do have a compass app on my phone, but that's no fun!

I would ordinary navigate using the North Star, but the atmosphere is usually acting against me, and it is quite hard to see anything through the clouds. There are only a few days when I ever see any stars at all, let alone useful ones!

Though I take it that it's a fairly inaccurate method of navigating. Blowing the clouds away would probably be more effective  ;D

Re: Navigating with the moon and a watch

PostPosted: Tue Sep 20, 2011 6:05 pm
by Steve M
When I was out on back roads at night, before the days of GPS, cloud cover could be plus. I could see city lights reflecting off the bottom of the clouds from 40 miles away. Although that doesn't tell you what direction your going it does usually get you back to a main road.

Re: Navigating with the moon and a watch

PostPosted: Tue Sep 20, 2011 6:14 pm
by Club508
Club. It's in the middle of the night. You aren't just gonna get out and ask for directions. Maybe thieves, Murderers e.t.c are out there :o

If you ask me, it's [glow=yellow,2,300]more manly [/glow]to ask for directions and make it home than to run out of fuel and be completely helpless.


This has sparked off because a friend of mine has become lost in country lanes just minutes off from where they're meant to be heading (though, [glow=yellow,2,300]she[/glow] is the sort who would get lost on a straight road). So I thought...


Just to clarify ::)

Whoops.  There goes that.  :o :o :o

Sorry. :-X