With the celestial poles on the horizon, all stars appear to rise in the east and set in the west for observers at the equator. Observers can never see all 88 constellations from a single location on Earth.
Another frequently asked question is “Why do the stars rise in the east?”.
Earth rotates or spins toward the east, and that’s why the Sun, Moon, planets, and stars all rise in the east and make their way westward across the sky. Suppose you are facing east – the planet carries you eastward as it turns, so whatever lies beyond that eastern horizon eventually comes up over the horizon and you see it!
Where do constellations get their names?
Constellation names that come from Greek mythology and figures from Greek and Roman myths are the best known. They were created and documented by the Greek astronomer Ptolemy.
They also created some wonderful, mythical stories to go along with these heavenly pictures. The myths of the constellations are tales about gods and monsters as well as villains and heroes. One may think that people don’t rely on these stories anymore, but if they look closely, they just might find them sneaking into everyday life.
Now, constellations are defined as areas of the sky – not as star patterns – with borders clearly defined by the IAU. Ptolemy, as well as many who came after him, saw constellations as asterisms and identified stars by their position within them.
While the astrology constellations were invented in the Near East, they are now thought of as a legacy of the Greco-Roman world. Many constellations in modern astronomy were known to the ancient Greeks. Often, the constellations were said to be images of figures and symbols from Greek mythology.
Another common inquiry is “How many Greek constellations are there?”.
One frequent answer is, greek constellations are the 48 ancient constellations listed by the Greek astronomer Claudius Ptolemy in his Almagest in the 2nd century CE. All but one of these constellations have survived to the present day and are officially recognized by the International Astronomical Union (IAU).
How do the constellations change as the Earth spins?
As our planet spins on its axis, we see different constellations, with stars appearing to move across the sky from east to west, just as the Sun rises in the east and sets in the west from our point of view.
Constellations by Month Constellations that can be seen in the evening sky change from month to month. Stars rise and set four minutes earlier each night and, as a result, we see constellations rising and setting two hours earlier each month.
When is the best time to see the constellations?
Each constellation is best seen in the evening sky at a certain time of year, whether it only briefly shows up above the horizon or it is visible throughout the year from a certain location. Below is the list of constellations visible at 9 pm each month.