NORTH TO 10 deg. SOUTH.]
In the front part of the book, after the long calendar, and the tables
relating to the sun and the moon, will be found about thirty pages of
tables headed, in large black letters, with the names of the
planets--Mercury, Venus, Mars, Jupiter, Saturn, etc. Two months are
represented on each page, and opposite the number of each successive day
of the month the position of the planet is given in hours, minutes, and
seconds of right ascension, and degrees, minutes, and seconds of north
and south declination, the sign + meaning north, and the sign - south.
Do not trouble yourself with the seconds in either column, and take the
minutes only when the number is large. The hours of right ascension and
the degrees of declination are the main things to be noticed.
Right ascension, by the way, expresses the distance of a celestial body,
such as a star or a planet, east of the vernal equinox, or the first
point of Aries, which is an arbitrary point on the equator of the
heavens, which serves, like the meridian of Greenwich on the earth, as
a starting-place for reckoning longitude. The entire circuit of the
heavens along the equator is divided into twenty-four hours of right
ascension, each hour covering 15 deg. of space. If a planet then is in
right ascension (usually printed for short R.A.) 0 h. 0 m. 0 s., it is on
the meridian of the vernal equinox, or the celestial Greenwich; if it is
in R.
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