What does steering by a star mean?

Answer 1

The stars move very very slowly from our perspective because they are so far away. Polaris, sometimes called the North Star, is and has been for millennia, located directly above the northern pole of the earth's axis, which means that if you are in the northern hemisphere and you need to know where north is to be able to steer a ship at sea, the North Star will give you that information. The Southern Cross performs a similar function in the Southern Hemisphere.

If you are sailing near the equator, the pole stars will be near the horizon and may be hard to see. However, if you know the constellations and particularly the signs of the zodiac, which are on the ecliptic, you should still be able to calculate your directions more or less.