1 22 
THE GUIDE TO NATURE 
Taurus. Thus Orion and the adjacent 
constellations contain half of these 
stars. The only other constellation 
which contains more than one is Ursa 
Major, which has three. This constel- 
lation is also visible now. In October 
only ten of these bright stars were 
visible. We also have the Milky Way 
•crossing the heavens through the 
zenith. Many of the brighter stars are 
found near the Milky Way. 
On Figure i have been drawn two 
-circles of equal size. The southern 
one is redrawn as Figure 2. In it are 
contained as mentioned above fifteen 
stars brighter than the 2.0 magnitude, 
which is half of all that are ever seen 
liere. The circle has a radius of about 
thirty degrees, and contains an area 
equal to nearly an eighth of that of the 
whole map and a tenth of the entire 
sky ever visible here, or one-fifteenth 
of the area of the entire celestial 
sphere. This means that this circle is 
more than eight times as rich in these 
brighter stars as the rest of the sky. 
In Figure 2 this very important re- 
gion is redrawn. The numbers on the 
stars indicate the order of their bright- 
Figure 2. Orion and his neighbors — the 
finest section of the sky. 
ness. Number one is Sirius, the bright- 
est, and fifteen to the right of it is Beta 
Canis Majoris, which is a trifle brighter 
than 2.0 magnitude. The names of the 
stars to seven inclusive are Sirius, 
Rigel, Procyon, Betelgeuse, Aldebaran, 
Pollux and Castor. Number nine is 
Bellatrix. Individual names are not 
usually applied to the others. 
The northern circle on Figure i is 
of the same radius and area as the one 
in the south which we have described. 
It contains not even one star as bright 
as 2.0 magnitude. The north star or 
Polaris is the brightest star in the 
circle. There is thus a very great dif- 
ference between the brilliance of the 
stars in the north and those in the 
south at this time. It is this brilliance 
of the southern sky which helps to give 
the impression that the stars shine 
much more brilliantly in winter than 
in summer. There are actually more 
bright stars to be seen without regard 
to the condition of the atmosphere. 
The Planets. 
Neptune is the only planet whose 
position is such that it is within the 
limits of our map. This planet cannot 
be seen with the naked eye. No planet 
visible to the naked eye could be shown 
on these maps since July last. This, 
however, is the last month in which 
this will be true, for both Jupiter and 
Saturn are just a little beyond the 
eastern horizon. They can be seen 
before midnight now and will be with- 
in the limits of the map next month. 
From that time we shall have at least 
one of the brighter planets visible until 
the end of the year. Neptune becomes 
an evening star February 3. Uranus 
becomes a morning star February 9 
but remains close to the sun for several 
months. Jupiter and Saturn are in the 
constellation Virgo and Mars in Libra. 
At the end of the month Mars will be 
just north of Antares, the star whose 
name means the rival of Mars. 
^ ^ ^ 
Jupiter’s Satellites. 
Those who have small telescopes and 
Avho have been interested in observ- 
ing the motions of the satellites of 
Jupiter will find them interesting on 
the mornings of February 7 and Febru- 
ary 23. On the first date, the first and 
second satellites are eclipsed at the 
same time from 1 156 to 4 :2i A. M. 
Eastern Standard Time. It is on the 
morning of February 23, however, that 
they are most interesting, as many 
things happen then. First satellite 
three conies between the sun and Jupi- 
ter at 10:32 P. M. Eastern Standard 
Time February 22 so that we see its 
shadow begin to cross the planet. At 
11:29 the shadow of satellite two be- 
gins to move across the planet for a 
similar reason. The four brighter satel- 
lites themselves are still visible. At 
12:10 A. M. satellite one enters the 
