Constellation separation

How many kilometers is Andromeda from the earth?

People often ask the question "How far is a constellation from the earth".

Friends who ask questions simply don't understand what a "constellation" is.

Constellation is an artificially divided area for people to identify the starry sky. From the earth, any celestial body located in this area, no matter how far or near, belongs to this constellation. Theoretically, all celestial bodies in the region belong to this constellation as long as they leave the earth's atmosphere.

For example, "Mars is currently running in Andromeda", then Mars belongs to Andromeda during this time. When Mars was closest to the Earth, it was only over 50 million kilometers. The distance of Andromeda alpha star (Chinese name Cebi II) is 100 light years; The distance of Andromeda beta star (Chinese name Milac) is 199 light years. The distance of Andromeda π (Quezon VI) is 660 light years. The most famous galaxy in Andromeda, M3 1, is 2.54 million light years away from the Earth. In Andromeda, there are many deep space objects, mainly some more distant galaxies, with a distance of more than 65.438+0 billion light years.

Therefore, for any constellation, it cannot be explained by "how far". If we must say how far a constellation is from the earth? That's the distance between this constellation and the earth from outside the earth's atmosphere to infinity.