Do you know your north?

Heh. In the Denver area, that's easy.

That's west. (See the Rockies?)

That's east. No mountains. In fact, when you top that hill, it's plains as far as you can see...all the way to the Mississippi River, 600 miles away. They don't call the Great Plains "Great" for nothing.

Facing the Rockies, north is to your right.

But why should you care?

Let's say that you're hiking somewhere other than Denver and you suddenly realize that you don't know where you are? Even if you have a map, you have to orient the map to your surroundings and the way you do that is to point north on your map (there will be a symbol pointing north just for that reason) toward geographic north.

You could just choose a direction and start walking. Surely a straight line will bring you to a road or stream or something you can follow out.

The problem there is that humans are very bad at walking in straight lines. They're much better at circles. People have a dominant side. If they're right handed, their stronger right side tends to push them to the left.

The way to walk in a straight line is to find a landmark and walk to it. When you get there, sight back to where you came from and extend that line of sight in the direction you're going, find another landmark, and walk there. Repeat.

But it's best if you have some idea of where you're going. Do you remember a road to the east of you? Is there a town somewhere to the southwest? Your reference is north.

When you face north, east is to your right, west is to your left, and south is behind you. And the sky will always tell you where north is. 

At night, Polaris, the pole star is due north (actually, it is off by about a degree but it's good enough for navigating on land.) If you know any objects in the sky, you should know Polaris, the Big Dipper, and Orion. The Big Dipper is hard to miss because it looks very much like a...well, big dipper. The two stars in the outer edge of the dipper are called the "pointer stars" because they point straight up at Polaris.

(South of the equator, Polaris australia is a very dim star, so you have to find where it should be by following the upright of the Southern Cross.)

If you find Polaris, you've found north so just walk straight toward...oh, wait, it's night. You shouldn't be walking around in a strange forest at night. Just wait until morning and, okay, where was Polaris, again?

Well, look for moss on a tree.

Eh, that's not a reliable way to find north. Moss likes sunshine and most of the sun in the Northern Hemisphere comes in from the South so, yes, mosses like southern exposures but they grow where they can. In dense forests, you can't trust them.

So, here's one.

Set up a vertical post (what astronomers call a "gnomon" - a rod used to cast a shadow or sight some object) and, at the top of its shadow, drive another rod into the ground. In about an hour, come back and place another rod at the tip of the gnomon's shadow (it will have moved). Strike a line from the gnomon halfway between the other two rods - that points north. A line from the second rod to the third points east.

The idea is that the sun rises in the east and sets in the west, and in the northern hemisphere, the sun is to the South, so the sun's shadow points north and moves from west to east. The problem is that this method depends on when you mark the shadows.

In the picture above, a line drawn from the rod at the left to the nearest rod points due north because I placed them at solar noon (not at Daylight Savings Time noon). At solar noon the sun is due South.

If you place the rods an equal time before and after noon, this method works.

Don't know what time it is? Well, start before noon and place small markers every so often at the ends of the gnomon shadow - maybe use little rocks or stick small twigs in the ground. Where the end of the shadow is closest to the gnomon - that's solar noon. Draw a line from the gnomon to that point and you have north.

If you spend a lot of time outdoors and pay attention to where the sun is, you can get to where you can just look at the sun and tell about what time it is and where north is.

Keep in mind that, in the Southern Hemisphere, you have to look for where the southern pole star would be if you could see it, and the sun will be in the north during the day.

A universal sundial

A world globe can be used as a sundial that can tell you the time of day anywhere on Earth, time of sunrise and sunset, how the seasons work, and many other things. All you have to do is orient it in the same direction relative to the sun as the Earth. That way, it models Earth in space. Here's how you do it.

You will need a surface that can be tilted (and, possibly a clamp for the base of the globe to keep it from tilting over. Alternately, there are globes that can be tilted in respect to the base.) You will also need a mini-gnomon. A gnomon is just a vertical rod that will cast a shadow in the sun. It has to be small enough to position on the globe's surface. I used a plastic bottle cap and drove a screw through the center from underneath. (The screw should be as near a right angle to the surface of the cap as you can make it. You can test it with a carpenter's angle or even the sides of a sheet of paper.) After using a carpenter's level, or a phone app level to level the surface you will place the globe on, place the cap on the surface and mark the edge at the point north of the screw. Use a magnetic compass or a phone app but don't forget to look up the correction for true north from where you live and add or subtract it from your compass bearing. (Do an Internet search for "magnetic declination".)

With the line between the screw and the edge mark pointing north, make another mark with an erasable marker at the end of the screw's shadow from the sun.

Now, set your globe on the surface with the north pole pointing north (according to your compass with the correction to true north.). Rotate the globe until your position is on top.

Now for the fine tuning. Place the mini-gnomon pointing north directly over your position on the globe. If the sun's shadow on the globe and the sun's shadow on the Earth are oriented the same, they will both be oriented the same in space in respect to the sun, so tilt and rotate your globe until the tip of the screw's shadow touches the mark you made earlier at the shadow's tip. Your globe is now aligned.

What time is it? One way to tell is to watch your mini-gnomon to see when it's shadow is shortest - that's solar noon. During daylight savings, the local time will be an hour behind solar noon.

You can find where on the globe that it's solar noon by moving the mini-gnomon around to find the place where it's shadow is shortest. That will be a line of longitude. Knowing that every 15 degrees of longitude is an hour will allow you to calculate the time anywhere on Earth (at least, while the sun is out.)

You may have heard that the sun is directly overhead on the equator at noon each day. Try it out.

When it's solar noon where you are, place the mini-gnomon directly over your position and slide it straight down your line of longitude to the equator. Does the screw cast a shadow? Not if it's one of the two annual equinoxes. On any other day, the sun will be exactly overhead somewhere north or south of the equator.

You can easily see where sunset and sunrise is by finding the day-night divider line on your globe.

At my current time, here, sunset is slowly creeping off Africa into the Atlantic.

There is a lot you can do with the universal sundial. Can you use a thermometer to measure differences in temperature on the surface of your globe according to the angle the sun is shining on it? That's what causes the seasons.

Once you have a globe oriented, you can use a clamp or clay or some other way to freeze it in position and make a cover to keep it out of the weather. Then you can use it all year.