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THIS AN ASTRONOMY QUESTION

Describe a general rule for how the angle that the parallels of declination make with the horizon are related to the latitude of the observer.

User Kirakun
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Answer:

The positions of your north celestial pole and south celestial pole change as you change latitude on the Earth, as you move north or south. At the Earth's equator, the Celestial Equator is directly overhead, and the poles are on opposite sides of the horizon. All stars are visible as they rise, culminate at the meridian, and set. As you move north, the Celestial Equator mirrors your movement, moving south the same number of degrees away from the zenith. The altitude of any star will change with the observer's latitude (as well as the time of night).

Note: only the altitude of the star changes NOT their coordinates. The star's celestial coordinates remain the same.

Explanation:

Declination is measured in degrees north (+) or south (-) of an imaginary line called the Celestial Equator (CE). The Celestial Equator is the projection of the Earth's Equator onto the Celestial Sphere. The CE has a declination of 0 degrees, by definition. At dec = +90 degrees (90 degrees N) is the North Celestial Pole (NCP), the projection of the Earth's North Pole onto the Celestial Sphere. The South Celestial Pole (SCP) is at dec = -90 degrees.

An Example would be:

You move 30 degrees North of the equator, hence, the Celestial Equator has moved away from the zenith, 30 degrees to the south.

While the NCP has risen 30 degrees into the sky and the SCP has sunk 30 degrees below the horizon.

If you moved south, the opposite would have occurred as the Celestial Equator moved north of the zenith.

User Gjijo
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