Being a navigator and a pilot, I tend to watch the skies during both the day and nighttime hours.

My challenge is to determine what direction true north is in relation to your own position when you watch the sun rise or set. Mark the true direction of the sun as it rises or sets, as the case may be.

You might want to think about what hemisphere that you are in.

You might also find it interesting marking the bearing of the moonrise and moonset.

I will apparently be the first to admit that I don't have a clue as to how to find true anything from where the sun/moon rises/sets. My GPS will tell me all of that and more, but I suspect that would be considered to be cheating. I can do pretty well at finding north from other means though...

In fact, in order to find the really true north, you have to consider also the date and time of observation, your geographical location, your altitude, altitude of the horizon line, the temperature in your place and temperature gradient in atmosphere along the direction line to the Sun, the same for air pressure, and for air humidity. Everything else is just a basic math i.o.w. the answer depends on precision (or task) you are going to achieve from such an observation. Otherwise the answer is as simple as pointing to the right looking at sunset, and to the left at sunrise

Hey OBG,

You can hang out with me if needed. I have been told more than once that I am the south end of a north bound horse. You'll quickly learn which way north and south are from that stand point.

I do this pretty much in the night time since I do a lot of amateur astronomy. I the daylight hours, (when not sleeping) I usually am familiar enough with the area I am visiting to know which way north is. Though a compass and GPS do come in handy from time to time.

Still, it's a very useful tip.

Stargazer

I'm with OBG. I have no clue how to get anything more than a rough guess from rising and setting suns and moons.

But then I'm rarely far from a compass and/or a GPS.

If you have a clear view of the horizon and can see both sunrise and sunset, a line between those two positions is East-West, 90 deg offset is North (point your right arm at sunrise and your left arm at sunset and you should be looking at North).

If you are in the Northern hemisphere, the sun is on the South side unless you are really near the equator in mid-summer.

Is that what you mean or is this a trick question?

"...Otherwise the answer is as simple as pointing to the right looking at sunset, and to the left at sunrise..."

That works for me!!!

"...Hey OBG, You can hang out with me if needed..."

Considering where you live, we might take you up on that offer some day!!!

Is it just me or wouldn't that require you to say put from sunrise to sunset before going anywhere? That wouldn't be practical as you'd only be able to get your bearings once a day...and only if you'd been sitting put all day.

My experience with the bush is that you can't properly see sunrise and sunset anyhow. The bush can be so thick at times you're lucky to see much sun at all.

wildman800,

It seems to me like you are asking for how to take and calculate an amplitude. With an amplitude you observe and take a bearing of the sun as it rises or sets, then you calculate what the true bearing of the sun is based on it's declination and your latititude.

See pp. 284-286: http://www.irbs.com/bowditch/pdf/chapt17.pdf

Note that that time to take the bearing with the sun is when the lower limb of the sun is about 2/3 of the sun's diameter above the visible horizon.

You might also be able to take an azimuth at that time. But IIRC, and I have not taken on since the late 80s, an amplitude is easier to figure out.

Also, IIRC, amplitudes are very accurate and because the bearing of the sun chages little as it approaches and is on the horizon.