The red end of a compass needle, the one traditionally indicating the direction toward the magnetic north pole, is the "north seeking pole" of the compass needle. The geomagnetic north pole is the only point where that end of the compass needle would point straight down, if the suspension allowed. At the geomagnetic south pole the other end of the needle would point straight down and the north-seeking end would point straight up.
Are you trying to claim that what we read in wikipedia is a lie?
The North Magnetic Pole is the point on the surface of Earth's Northern Hemisphere at which the planet's magnetic field points vertically downwards (in other words, if a magnetic compass needle is allowed to rotate about a horizontal axis, it will point straight down). There is only one location where this occurs, near (but distinct from) the Geographic North Pole and the Geomagnetic North Pole. http://en.wikipedia.org/wiki/North_Magnetic_Pole
Not in this case; what you quoted sounds pretty much like what I was saying. How do you think it's different? As already noted, Wikipedia is crowd sourced - anyone can make entries - so it's not infallible.
As usual, the point those illustrations are intended to convey is completely wrong. There's no requirement for the magnetic field lines to be completely level (zero inclination) for a compass to work. Good compasses can cope with a moderate inclination using low-friction bearings that work well even with a fair amount of inclination. If the inclination is very high, you're getting close to the magnetic pole, and the general usefulness of a magnetic compass drops considerably since it can easily be as much as 180° off for finding true north. Cheaper ones will counterbalance the needle to offset the inclination; these will work reasonably well in a certain range of magnetic latitudes, but probably will "stick" if used in the opposite hemisphere.
My wife and I will be going to Patagonia next week for ten days. From there we go to Antarctica for three weeks. Will be doing some hiking but just day stuff. Here is a question for all of you as I can't seem to find a straight answer on the Internet - does a compass work in the southern hemisphere? Will the magnetic needle still point north? This is not a huge issue for me but just wondering. Thanks for your help!
03.25.2013. after he had come back he wrote this:
I just got back from my five week Patagonia/Antarctica trip last week. Just before leaving for the Antarctica segment of the trip, I did an experiment in the city of Ushuaia which is located on the southern tip of South America. It's latitude 54°48′south. I visited a local park that had a large decorative compass made out of stone. I used it to get my north, south, east, west bearings. Side by side I set up a North American compass, a global compass, and an iPhone compass. All three pointed in the exact same direction - north (see photo below). I mentioned my experiment to a guy I met from Australia. He said, "Of course they pointed north. A compass will point north unless you sitting on the South Pole..." As I mentioned in my previous post, this was not a huge issue for me but it was fun finding out the answer. http://www.energeticforum.com/255802-post1.html
Here is the picture of his compasses:
Those Bruntons and Suuntos are nice compasses. Apparently they work well at about -45° magnetic inclination. I'm not surprised, but it's good to see. For reference, the USA is at about +60° magnetic inclination, so, if anything, this was easier for those compasses.
It's latitude 54°48′south, so would you be so kind to demonstrate to us how in this latitude compass needle can point towards North if the Earth is round?
Sure. The compass needle lines up with the magnetic field lines, which (by convention) "emerge" from the surface in the southern (magnetic) hemisphere, follow a curved path toward the north magnetic pole, and dive back into the surface in the north (magnetic) hemisphere. Here's a picture from a Google search on
magnetic field lines earth and scrolling through the myriad of images offered[nb]Note that the "bar magnet" inside the Earth representing the source of the Earth's magnetic field in the illustration has its S end in the northern hemisphere. Because of this the N pole of your compass needle points to the north, toward this end of the "bar magnet".[/nb].
The mechanical compass needles shown are free to rotate in azimuth, but constrained from tilting too much vertically, so they align with the horizontal component of the direction of the field lines in the area, which are generally N-S in southern South America. The phone contains a magnetometer that can determine the orientation of the field lines in, possibly in 3D (and probably their intensity), and an app running on the phone displays this information as a conventional compass display.
Where is North (geometrically) if we are trying to determine it (North) at this latitude (54°48′south)?
Same as it is everywhere except the poles themselves. North (
geometrically) is 180° from south. In the picture, magnetic north is to the upper right (south to the lower left), in the direction the red ends of the needles are pointing. Geographic north is probably about 15° east of where the needles are pointing.