FAQ

How many constellations are there?

The International Astronomical Union recognizes 88 official constellations covering the entire sky. 36 were listed by Ptolemy in the 2nd century. The remaining 52 were added during the Age of Exploration, mostly in the southern sky. The final list was established in 1922 and the boundaries were set in 1930.

What is the largest constellation?

Hydra the water snake at 1,303 square degrees. Virgo is second at 1,294, Ursa Major is third at 1,280. The smallest is Crux the Southern Cross at only 68 square degrees. The sizes vary enormously, with the largest being nearly 20 times the size of the smallest.

What is the zodiac?

The zodiac is a belt around the sky about 18 degrees wide centered on the ecliptic, the apparent path of the Sun across the sky. It contains the 12 traditional zodiac constellations plus Ophiuchus. The Sun spends varying amounts of time in each constellation, from about 6 days in Scorpius to 44 days in Virgo.