THE EARTH'S PLACE IN THE UNIVERSE 



17 



is the only star near the line which is as bright as the 

 pointers. 



5. Stars Visible all the Year. The constellations in 

 the northern sky are visible any clear night in the year from 

 all places in the northern hemisphere. 



Three well-known groups are the Great Bear, the Little 

 Bear, and Cassiopeia (sometimes called Cassiopeia in her 



FIG. 2. THE BIG DIPPER AND 

 THE NORTH STAR 



Distances in the sky are meas- 

 ured in degrees (1 = 1/360 of a 

 circle). The pointers are 5 apart; 

 using this distance as a measure, 



1. Estimate the distance between 

 the stars at the top of the Dipper; 



2. From either pointer in a straight 

 line to the end of the handle; 3. 

 From the North Star to the farther 

 pointer. 



* North Star 



* * 



Chair). A part of the Great Bear is known as the Big Dip- 

 per, and the tail of the bear is the handle of the dipper. The 

 tail of the Little Bear makes the handle of the Little Dipper, 

 and the North Star is at the end of the tail. Except for the 

 stars that form the outlines of the dippers, there are no 

 conspicuous stars in the constellations of the bears. 



To locate Cassiopeia, imagine a circle around the North 

 Star passing through the bowl of the Big Dipper. Look 

 about half-way around the circle from the bowl and you find 

 an open, sprawling, W-shaped figure. This is the brightest 

 part of the chair. (LABORATORY MANUAL, Exercise I.) 



