Some Useful Definitions
There are a few terms which we use a lot
when trying to understand the sky:
Latitude is a way of
describing where you are on the Earth between the equator and the
poles. If you're latitude is 45° North, then you are halfway
between the equator (latitude = 0°) and the north pole
The horizon is the plane which defines the half of
the sky that you can see.
Altitude is the angle between the object you are
looking at and your horizon.
The ecliptic can refer to many slightly different
ideas which all relate to the Earth's orbit. The plane in which the
Earth goes around the Sun is called the ecliptic. The ecliptic is
also an imaginary line in the sky along which the Sun appears to
travel as the Earth goes around the Sun. The path of the ecliptic
determines the zodiacal constellations; they are all constellations
through which the Sun appears to move as the Earth goes around the
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