I seem to remember from my childhood days at summer camp being told that although the Big & Little Dipper's can be seen in the Northern Hemisphere, and the Little Dipper pours into the Big Dipper, they can't be seen at the same time, meaning if I were to look up and see the Big Dipper I wouldn't be able to see the Little one. Is that true?

I believe that would depend on the time of year and your location. If you are far enough North you should be able to see both Ursa Major AND Ursa Minor, the Big Dipper and Little Dipper respectively. The most famous star in Ursa Minor is Polaris <../hr/0424.html>, the North Star. This is the star that is nearest to the North Celestial Pole. If you stood at the north pole, Polaris would be almost directly overhead. If you can spot Polaris in the sky, you can always tell which way is north. In addition, the angle of Polaris above the horizon tells you your latitude on the Earth. Because of this, Polaris was the most important star for navigating at sea.
To find Polaris, first find the Big Dipper. If you follow the two stars at the end of the cup upwards (out of the cup of the Big Dipper), the next bright star you will run into is Polaris. The distance to Polaris on the sky is about five times the angle between the two stars at the end of the cup of the Big Dipper. Because they are so useful for finding the all-important North Star, these two stars are known as the Pointer Stars. They are also called Dubhe <../hr/4301.html> and Merak <../hr/4295.html> (Merak is the one at the bottom of the
This site gives a listing of all of the constellations with links to whichever one you're interested in.
http://www.astro.wisc.edu/~dolan/constellations/constellation_list.html

[This message was edited by frankvan on 08-15-02 at 01:43 PM.]

FrankVan, do you know what instuments navigators used to find their latitude in the early sailing days? The pitching and rolling deck of a ship at sea would not allow enough accuracy, would it?

The quadrant and the astrolabe were two early instruments used to determine position at sea but, as you say:
The drawback for both the quadrant and the astrolabe was the movement of the ship, which made it difficult to make an accurate measurement. The cross-staff , invented in the sixteenth century, solved this problem.
CROSS-STAFF - An early sixteenth-century instrument for measuring the altitude of a heavenly body. It consists of a square shaft and a sliding cross-piece set at right angles to the shaft. The shaft end is held at the observer's eye and the cross-piece positioned to line up with the sun and the horizon. The cross-piece marks a point on the shaft that is referred to in a table of degrees and minutes.
http://www.mariner.org/age/earlynav.html

Also, Polaris is actually three stars orbiting each other at a very near distance.

on the subject of the north star... what star is refered to as the north star actually varries over time as the earth wobbles a little on it's axis putting different stars closest to due north. i don't remember how long it takes for the wobble to shift a new star into the north star position, but for our lifetimes at least the north star has been and will be polaris.

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Originally posted by methos5000:
on the subject of the north star... what star is refered to as the north star actually varries over time as the earth wobbles a little on it's axis putting different stars closest to due north. i don't remember how long it takes for the wobble to shift a new star into the north star position, but for our lifetimes at least the north star has been and will be polaris.

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In our lifetimes is right, in 14,000 years it will be Vega and in another 14,000 years it will again be Polaris.

[This message was edited by frankvan on 08-16-02 at 01:03 PM.]

[This message was edited by frankvan on 08-16-02 at 01:04 PM.]

Thanks frankvan. I knew it was much longer than our lifetimes, I just couldn't remember exactly how long so i didn't want to get to specific and risk being wrong

The was a good link, it sounds like the Little Dipper is more visible in the winter sky than in the summer, so I'll be looking for it on some cold but cloudless winter night.

You're right, cold, cloudless winter nights are the best nights to watch stars because the crisp air sort of frezzes disturbances making them the clearest nights. Looking from on top of a hill is a good idea also.