Where is the two dog constellation _ Where is the two dog constellation?

How many constellations are there in the sky and where did the constellations originate?

Constellation refers to a group of similar stars projected on the celestial sphere. Different civilizations and historical periods may divide constellations differently. Most modern constellations evolved from the traditional constellations of ancient Greece, and the International Astronomical Union accurately divided the whole day into 88 constellations.

Western constellations originated in Babylon, one of the four ancient civilizations. It is said that there are more than 20 constellation names, such as the so-called zodiac 12 constellation, which was born in Mesopotamia about 5000 years ago. Since then, the Babylonians have continued to divide the sky into many regions and put forward new constellations. Around 1000 BC, 30 constellations have been proposed. Ancient Greek astronomers supplemented and developed the Babylonian constellation and compiled the ancient Greek constellation table. In the 2nd century A.D., Ptolemy, an ancient Greek astronomer, synthesized the astronomical achievements at that time and sorted out 48 constellations. Connect the main bright stars in the constellation with imaginary lines, imagine them as images of animals or characters, and give them appropriate names in combination with fairy tales. This is the origin of the constellation name. Most of the 48 constellations in Greek mythology live in the northern sky and north and south of the equator.

1928 The International Astronomical Union officially announced 88 constellations commonly used in the world. At the same time, it is based on the vernal equinox and equator of 1875. According to the different positions of the 88 constellations on the celestial sphere and the appearance of the stars, they are divided into five regions, namely, the Northern Celestial Constellation (5), the Polaris Constellation (40 ~ 90, 19), the Twelve Constellations (12 constellation near the ecliptic on the celestial sphere) and the Zodiac Constellation (19). The 88 constellations of the whole day are:

Northern Sky Constellation (5): Ursa minor (closest to the north celestial pole), Ursa major, Cassiopeia, Draco and Cepheus. Polaris constellation (19): Scorpio, Andromeda, Lupo, Auriga, Canis major, Foxes, Cygnus minor, Perseus, Shepherd, Pentecost, Backrow, Corona Nordica, Tmall, Lyra, Dolphin, Pegasus, Triangle. Zodiac (12): Cancer, Aries, Gemini, Aquarius, Virgo, Leo, Taurus, Pisces, Capricorn, Scorpio, Libra and Sagittarius. Twelve constellations (10): Sagittarius, Canine, Eagle, Ophiuchus, Ophiuchus, Sextant, Ophiuchus, Unicorn, Orion and Whale. Southern Constellations (42 in total): Temple of Heaven, Picture Frame, Fly, Mountain Case, Indian, Tian Yan, Flying Fish, Long Ruler, Swordfish, Clock, Rhododendron, Southern Triangle, Compass, Dragonfly, Telescope, Aquarius and Southern Cross (small constellation).