TO KNOW THE STARRY HEAVENS 
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considered as forming an imperfect let- 
ter A (see Figure 1). The eastern side 
of the A is the so-called segment of 
Perseus. Just above the top of the A, 
at 1 ), lies the double cluster in Perseus, 
distinctly visible to the naked eye and 
a splendid object in small telescopes. 
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The Planets in December. 
Venus alone of the brighter planets 
is visible in the early evening. This 
planet may be seen in the southwest in 
the early evening. It is not within the 
limits of our map until the end of the 
month. It is then just on the edge. The 
map is for nine o’clock, whereas it be- 
comes dark much earlier, so that Venus 
first. In this case the shadow com- 
pletes its transit 7 hours and 32 minutes 
before the satellite begins its transit. 
Since this is the outermost of the four 
brighter satellites and the event occurs 
almost exactly at quadrature, this in- 
terval is about the longest possible for 
one of Jupiter’s satellites. 
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The Earth at Perihelion. 
The earth was at perihelion — that is, 
at the point of its orbit closest to the 
sun — on January 3. It will be at peri- 
helion again just when the whistles are 
blowing to herald tbe New Year in 
Eastern Standard time. It occurs 
earlier by the Central and Mountain 
may be seen earlier in the evening. It 
is so bright that it may be seen in very 
strong twilight very soon after sunset 
and before the stars come into vietv. 
Uranus is in Aquarius, but is not vis- 
ible to the naked eye. Jupiter and 
Saturn are not far apart in Leo and 
may be seen late at night. Neptune is 
not visible to the naked eye. The other 
planets are too near the sun to be seen. 
On December 9 Jupiter is at quadra- 
ture — that is, the line from the earth to 
Jupiter is perpendicular to the line from 
the earth to the sun. On this day the 
fourth satellite of Jupiter makes a 
transit over the face of Jupiter. The 
satellite also casts its shadow on Jupi- 
ter. The shadow crosses the planet 
Times. Thus this year there are two 
times when the earth is at perihelion, 
which is unusual. Next year the earth 
will not pass perihelion at all by the 
times used in this country. 
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The Pleiades. 
The Pleiades are better known than 
any other group of stars in the sky un- 
less it be those of the Big Dipper. 1 hey 
do not form a constellation, but are 
only a part of the constellation Taurus. 
They are located at E, Figure 1. As 
they are a compact group not well rep- 
resented on the small scale of Figure 1. 
a larger scale map is found in Figure 
2. To the naked eye only the six stars 
joined by the lines are easily seen. None 
