Right Ascension and Declination
Aside from their catalog numbers (which stand in place of names for most places we've never been),
stars are given referencial digitations denoting their particular position in the sky, known as Right Ascension and Declination
- this is a time-worn system of coordinates, which assumes all observations (needing these numbers, anyways) will be made from planet Earth
- basically based on Longitude and Latitude; kinda the same concept.
For Right Ascension, imagine Time Zones (or peel an orange and notice the slices)
- and like an orange section, these regions are widest at the equator and narrowest at the poles
- 24 equal sections known as Hours (further divided into Minutes and Seconds).
For Declination, measure by Degrees, (also further divided up into Minutes and Seconds),
relative to the equator (positive and negative, 0-90).
The North Pole is +90� and South Pole is -90� ..... and 0� would be anywhere on the Equator.
Roughly corresponding to the Celestial Equator, is the Ecliptic,
which is the path that the Sun and Moon and all the Planets follow (except for Pluto) - basically the disc of the Solar System.
The Zodiac also kinda follows the middle of our sky,
and thus appears to turn around once per day, as diagramed above, in the outer ring.
Not all stars within each Sign of the Zodiac are within relative proximity to us or each other.
Some of the dim ones are very close to us, while many of the bright ones are very far away.
Some stars, known as Optical Binaries, appear to be orbiting each other
- but it is merely that they are on near exact line of sight, from our perspective, with respect to our position.
Therefore, Constellations (such as the Signs of the Zodiac) are not necessarily groupings of stars among themselves
- and most stars in most Constellations do not consider themselves to have anything to do with each other;
and any Constellation they might consider themselves to be a member of, might not be apparent to us.
Our sun, as a star in someone else's sky, is very dim compared to other stars
- and only a naked-eye star within a few light years or so
- maybe a dozen, or 20, depends on the sky.
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