Top 10 Most Popular Questions About Famous Constellations

~4 min

Everyone who regularly observes the night sky begins to wonder about constellations sooner or later. What is a constellation? How many of them are there? Why is the Big Dipper not a constellation? In this article, you’ll find answers to the most frequently asked questions from Star Walk 2 and Sky Tonight users!


What are the constellations?

A constellation is a group of stars that appears to form a pattern when viewed from the Earth. Constellations are completely imaginary – most of them were invented by ancient astronomers and used as memory aids for navigating the night sky.

What is the difference between a constellation and an asterism?

Asterisms differ from constellations in that they are not officially registered. Most asterisms are easily recognizable patterns of stars within a constellation. For example, the most well-known asterism is undoubtedly the Big Dipper in Ursa Major; another famous one is the Teapot in Sagittarius. Sometimes, an asterism can comprise stars from multiple constellations – like the Summer Triangle that includes the stars located in Cygnus, Lyra, and Aquila.

How many constellations are there?

The International Astronomical Union (IAU) officially recognizes 88 constellations that cover both northern and southern skies. Each constellation is a region of the sky, bordered by arcs of right ascension and declination. Any given point on a celestial sphere lies in one of the constellations.

How many zodiac constellations are there?

There are 12 zodiac constellations. The constellations are Aries, Taurus, Gemini, Cancer, Leo, Virgo, Libra, Scorpius, Sagittarius, Capricornus, Aquarius, and Pisces. Some think there are 13 or even more than 20 zodiac constellations. The reason is people confuse the zodiac constellations with the ecliptic constellations and the constellations of the zodiac belt. If you would like to explore these concepts in more detail, check our article on the zodiac constellations. Also, take our quiz about zodiac constellations: the best way to learn something is by practice!

How to find constellations in the sky?

The easiest way to find constellations (as well as individual stars, planets, and other celestial bodies) is to use stargazing apps, like Star Walk 2 and Sky Tonight. Just point your device up to the sky, and the app will show you the name and shape of any constellation above your head. For more detailed instructions, check our video tutorials on how to find celestial objects via Star Walk 2 and Sky Tonight.

Some constellations also hold exceptionally bright stars or recognizable star patterns, which make it easier to identify them in the sky. You can see examples of easy-to-find constellations in our infographic: check it out and try to spot these constellations tonight!

7 Constellations Everyone Can Find
Learn how to easily find famous star patterns and constellations in the night sky. Discover interesting facts about each of the constellations.
See Infographic

Why do constellations not look like their names?

Don’t forget that constellations are products of ancient people’s imagination. The human brain has a tendency to see meaningful patterns in random structures, and the final result is highly individual. Where the Greeks saw Orion the Hunter, ancient Chinese astronomers saw the White Tiger and Vermilion Bird. If you were to name constellations, you’d probably come up with totally different shapes and names.

What is the biggest constellation?

The largest of 88 constellations is Hydra – it measures 1,303 square degrees and takes up 3.16% of the night sky. It is also the longest constellation, spanning over 100 degrees in length. If you live in the Southern Hemisphere, you can find this constellation by looking for the Head of Hydra asterism, located between bright stars Regulus and Procyon. Or you can simply use a stargazing app!

What is the smallest constellation?

The smallest of 88 constellations is Crux: it only takes up 68 square degrees. Still, it is one of the most popular constellations of the Southern Sky, as its brightest stars form a cross-shaped pattern that is well-seen in the night sky and has been used for navigation since ancient times.

Which constellation holds the brightest star in the northern sky?

The brightest star in the night sky is Sirius; it can be seen from both the Northern and Southern Hemispheres. Sirius resides in the constellation Canis Major and shines with a visual magnitude of -1.44.

What are three stars in a row called?

The famous asterism of three stars in a straight line is the Orion’s Belt situated in the constellation of Orion. It consists of the three bright stars Alnitak, Alnilam, and Mintaka. Looking for Orion’s Belt in the night sky is the easiest way to find the constellation of Orion.

15 stars everyone can find Intro
Learn how to identify the most famous stars: Polaris, Sirius, Arcturus, and many others. Familiarize yourself with the night sky using this infographic!
See Infographic

Top questions about famous constellations: bottom line

A constellation is a group of stars that seem to form a pattern in the sky. There are 88 officially recognized constellations. The biggest of them is Hydra, and the smallest one is Crux. We hope you’ve learned some interesting facts from our article and maybe cleared up some misconceptions about constellations. If some of your questions were left unanswered, don’t hesitate to ask them in the comments on our social media!