is true north polar; or using sphere;/north star= north.?

Question

ancient star charts indicate;true north is not north at all .living on a sphere shaped star/or planet.one must use the heavens too find north south east &west.v;i;a corner stone stars.the question remains as is.is true north polar or astro phisics/star trek knowledge.

Answer 1

That's a confusing question with poor grammar, but I think you are asking how do we determine true north.

There are two different "true" north directions:

1. Astronomic true north which uses the North Star (Polaris) as a reference, and

2. Geographical (or polar) true north which uses the earth's axis of rotation as a reference.

The two directions are very close to each other. Of course magnetic north varies widely depending on your position on the earth as well as over time. Scientists, surveyors, and navigators have to specify which north reference they are using to avoid any confusion.

Answer 2

"TRUE" north is defined as the northern end of the earth's axis of rotation. This direction can actually be found very accurately using gyroscopic techniques. However, prior to the invention of inertial navigation in the 1950s, there were two approximations for true north that were readily available:

magnetic north, as shown by any compass

approximate north, as measured by sighting Polaris.

Magnetic north varies significantly from true north, as the earth's magnetic north pole is actually somewhere around 83 deg north latitude (I don't really the longitude at the moment). Since the magnetic pole lies significantly distant from true north, a compass reading might not point anywhere near north, depending on your location on earth. Fortunately, this deviation is easily calculated, and is provided on most decent maps as a "magnetic declination" reading.

Using Polaris is more accurate, but not completely. As has been pointed out, the earth's axis actually points about 1 degree away from Polaris, but this is sufficiently accurate for most local navigation. However, this reference is not constant. The earth's rotational axis actually wobbles, with a rotation period of about 25,000 years. So, although Polaris has been the north star throughout recorded history (going back 5000 yrs or so), it won't always be.

Both of these vagaries are defeated by using a good gyrocompass, which will ALWAYS find TRUE NORTH.

Answer 3

Your question is not clear to me. The Earth spins around its axis every day. This axis points toward the pole star, Polaris (actually about 1 degree from Polaris). About 13,000 years ago, it pointed 23.5 degrees away from Polaris, in the direction of the star Vega. In about 13,000 years it will again point toward Vega.

Answer 4

tru north points towards our north pole, the north star indicatesn a direction to head towards. magnetic north is located in northern canada.