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40

If you look at the current time, and imagine yourself in the center a big analog watch, just place your shadow on the location of the hour's hand. Then imagine the location of the 12 o'clock hand, and exactly in the middle of the angle between those two hands is the north. Be sure to ignore daylight saving time (As the time your hand watch is showing during ...


40

This map (and the Wikipedia article) will explain why you don't have a problem (in the UK, I'm guessing), but others do, elsewhere. In the UK, you can ignore it at the moment, but you need to understand WHY you're ignoring it :) As an aside, compare this with the declination in 1872... Then, the declination error in the UK would have been between 20 and ...


32

Compasses are good equipment both spelunking and diving. Even the deepest cave you could go to is still near the earth's surface, geologically speaking. The earth's magnetic field is also essentially the same under water as above. If you are using a compass, what you need to be aware of is nearby magnets and large sources of iron. So if you were exploring ...


28

There seems to be a fixation with North in navigation. Step back to the basic purpose, why do we navigate? We navigate to get to somewhere or to find our way back. Knowing north is just one method of doing such. So predicating navigation on knowing which way is north is unnecessary. North isn't the goal, it's a reference for finding what you really want....


28

If there's a stick around and enough sunlight, I've found the stick method surprisingly accurate: Find a straight stick, around 2 feet long (length isn't that important) and plant it straight in the ground. Mark the end of the stick's shadow, perhaps with another short stick. Wait for about 15 minutes then repeat step 2. Draw a line between the two ends ...


24

Isolation and prominence are the two key criteria to classify a peak as an independent mountain. To understand the meaning I like the visualization from the German Wiki where "Dominanz" means isolation and "Schartenhöhe" means prominence: Isolation is the distance to the next point with the same height (radius) of a higher mountain. So the nearest ...


24

This depends highly on your location. Contrary to popular belief, the difference between the magnetic pole and the geographic pole is not the only reason for declination. As a matter of fact, the magnetic poles are simply defined as the points where the magnetic field points vertically. This is not the same as the pole of a anyway non-existing earth-magnet. ...


23

With fog, the only thing you're losing is extended visibility. This shouldn't throw off your plan too much, unless you were navigating by watching far away landmarks. If you were on a trail, stay on it. There's no need to wander around. If you can't see anything and traveling is becoming dangerous or you're not sure where you're going, then stop and wait ...


22

Where your magnetic compass points can be quite far away from the north shown on your map For example, on the line marked 30, your compass would point 30 degrees away from true north.


19

You need to know if you are in Northern Hemisphere or in Southern Hemisphere or nearby the Equator. If you are in Northern Hemisphere: First locate the Polaris. Its the last star in The Ursa Minor. I've had trouble in locating it sometimes. Many people do. So, if you are in such a situation, try locating The Ursa Major. The Ursa Major is located just to ...


18

If you can no longer see any trail signs, the best thing to do is go back the way you came until you find one and start searching in a circle from there. Never continue to go further assuming there is going to be a sign just up ahead. You may be right, however the risk of getting lost and something unfortunate happening is too great. If you become separated ...


18

If you need to walk on a compass bearing in poor visibility, stand still, and send someone out in front of you on the correct bearing for a distance (probably as far as you can see). Have them stand still, then walk to them. Repeat. It's slow going, but you will be walking on the correct bearing, and more accurate than just holding the compass out in front ...


16

I'd give them whatever my device or map provided me, and let them convert to whatever their devices or maps use. Anyone used to receiving lat/lon coordinates regularly should be able to convert from various formats to whatever they use internally. You're the one in trouble with limited resources. You're out there with a broken leg, lost, in the cold or ...


16

Yep! If you store your compass near objects that have strong magnets in them (such as your car speakers) it can demagnetize over extended periods of time. There are a few other issues your compass can run into that makes it less reliable as well. Air getting into the compass housing (in excess) Bubbles can form within the compass housing when doing big ...


16

Magnetic pole The distance from the rotational north pole varies over time -source By the time you read this, the north magnetic pole could be half the circumference of the planet away from the true (i.e. rotational) north pole. Thats over 20,000 km apart. It has been in the past. See magnetic pole reversal and rate of transition. Declination More ...


15

Basic celestial navigation: In the northern hemisphere, the star Polaris indicates north. In the southern hemisphere, you can use the Southern Cross, see Finding the south celestial pole.


15

The distance between the magnetic north and geographic north poles is not important for navigation purposes. What matters is the angle between them, which is called the magnetic variation or magnetic declination. The magnetic variation varies depending on where you are on earth, and also changes slightly from year to year. In Pittsburgh, Pennsylvania, it'...


14

Searching online I found lots of useful informations, like e.g. wiki says: The accuracy of step counters varies widely between devices. Typically, step counters are reasonably accurate at a walking pace on a flat surface if the device is placed in its optimal position (usually vertically on the belt clip). Although traditional step counters get affected ...


14

They're absolutely NOT the same thing. The distance varies. But it's about 500 miles. (http://www.livescience.com/41955-north-pole.html) Since its discovery in 1831, the magnetic North Pole has been around Canada’s Ellesmere Island, about 500 miles (800 kilometers) from the geographic North Pole. https://en.wikipedia.org/wiki/True_north


13

The simplest way (assuming you are in the Northern hemisphere) is to first find the Great Bear / Ursa Major / the Big Dipper / The Plough, and use the two end stars as a sight line. The star in Ursa Minor that they point to is Polaris, which is currently our Pole Star. This does change, but not noticeably in our lifetimes. (from http://www.themightyeagle....


13

Adding this mainly because it's a different kind of approach. The other ones are usually more practical, but this is an alternative that does not require remembering any constellations. If you have a rough idea and a camera, you can take a long exposure (30s minimum, more is better) and check which star in photo is the only one that does not move / stays a ...


12

A topographic map, as we see here, is made up of a number of lines.: Every point on a given line is at the same elevation. Where the lines get closer the slope is steeper, and vice versa. But that doesn't tell you directly which way the slope is going, so they put numbers on the lines - the slope goes up towards the higher numbers. These numbers indicate ...


12

I recommend visiting Yellowstone National Park (and Grand Teton National Park - they border each other and for $20 USD, you get a 1 week pass to both parks!). Here's what I recommend: Take Interstate 90 across South Dakota (or go up through Wisconsin/North Dakota, then drop - much more scenic in Minnesota/Wisconsin, and easier driving in ND than SD) ...


12

I think you already answered your own question. Most dedicated GPS devices are more rugged, have better battery life, and don't require a data connection to work well. A phone has a lot of power overhead and is fragile. There are a few possible advantages to a phone. If you're already going to be carrying one, it reduces the total weight required. It's ...


12

There are several ways to determine true north, especially when you have a map and compass: Competent maps, like most intended for backcountry hiking, will have the magnetic declination marked. This is usually in one of the corners. Take a look at any USGS topo map, for example. The compass will tell you the direction to magnetic north, and the map tells ...


11

If it's early morning, you'll note that the sun rises in the east. It additionally sets in the West. Normally, more plant-life can be found on the east side of a ridge (I don't have a source for this, I'm sure someone else can be more helpful) as it more fully receives light. Personally, I navigate almost exclusively by features and carry a contour map with ...


10

The distribution of sun east / west should be pretty close to the same. In the northern hemisphere, the south side of areas gets more sun due to the sun being more to the south (perpendicular to the equator). This doesn't necessarily translate into there being more vegetation on the south side of ridges though, it depends on the environment. Southern ...


10

On water, you can use the curvature of the earth to help you, and change your height instead of moving. According to the Boat Safe Kids web site, the formula for how far away the visible horizon is over water (in other words, how far you can see) is 1.17 * sqrt(eye height in feet) = (distance in miles) While wikihow says sqrt (1.5 * eye height in ...


10

Moss grows best in the shade (and damp, but most relevant here is shade). Because of the curvature of the Earth, in the northern hemisphere the north side of trees is shadier than the south side, so if moss grows on only one side of a tree, it is likely to be the north side. In the southern hemisphere, the whole thing is mirrored so the moss is on the south ...


10

Most GPS receivers in phones work not nearly as good as stand-alone GPS devices. Usually, one wouldn't notice this because phones use assisted GPS where they get the orbital data and/or almanac of the GPS satellites as well as the exact time from the GSM network. Also, they have a average position of the device. Without that data, phones are very slow ...



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