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 (latitude=90°).

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 Sun.

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