Category Archives: Asterisms
The winter sky is an excellent place to begin exploring the constellations that make up the night sky. Orion is the key, or signpost, for locating many of the other constellations in the winter sky. There are two convenient ways to locate all of the main constellations around Orion once Orion is located. Fortunately, Orion is easy to locate and well known to most people.
The first way is to follow lines made by pairs of stars in Orion. The second way is to locate the great winter hexagon of bright star around Orion.
The Constellations of the Winter Sky
If you live in the northern latitudes and you scan the sky from the southern horizon to the region overhead, you should be able to see the following constellations on a clear winter night: Orion the Hunter, Canis Major the Great Dog, Canis Minor the Little Dog, Taurus the Bull, Auriga the Charioteer, Gemini the Twins and the Pleiades star cluster. (See the map on the next page).
In Greek mythology, Orion was a great hunter who eventually offended the gods, especially Apollo. Apollo tricked Artemis, the Goddess of the hunt, into shooting Orion on a bet. When she discovered that she had shot Orion, she quickly lifted him to the heavens and made him immortal, where he now hunts eternally with his two dogs, Canis Major and Canis Minor. In front of him is his prey Taurus the Bull.
The myths surrounding Auriga the Charioteer vary, but it is an ancient constellation dating back to at least to the Ancient Greeks. Some say Auriga invented the chariot and others that he trained horses for the best chariots.
Gemini is a constellation made up of two stick figures known as the twins, Castor, who was a great horseman, and Pollux, who was a great boxer. According to one myth, Castor and Pollux (a.k.a. Polydeuces) were the sons of Zeus and Leda (from Leda and the Swan) and were hatched from an egg. Their sister was the beautiful Helen whose face launched a thousand ships to do battle in front the Trojan city of Troy.
Method 1: Using Pairs of Stars in Orion as a Guide
Finding Sirius and Canis Major
If you follow a line from the belt stars of Orion to the left and slightly down, you will come across a very bright star called Sirius, which is also known as the Dog Star. (See the arrows in the diagram to the right).
Sirius is the brightest star in the night sky so it is hard to miss. Once you’ve located Sirius you can locate the other stars in the constellation Canis Major the Great Dog.
Finding Procyon and Canis Minor
From there you should be able to see the other star that us easily visible. Together, the two stars make up the constellation Canis Minor, which is also known as the Little Dog. Along with Canis Major, Canis Minor follows Orion across the heavens on an eternal hunt.
Finding Aldebaran and Taurus
Following the belt stars to the right, you will pass just below the bright star Aldebaran and through the constellation Taurus, which is also known as the Bull.
Continuing on you will run across a fuzzy blur of stars closely grouped. These are the Pleiades, or the Seven Sisters.
Finding Capella and Auriga
Follow the bottom most star on the left and the left most belt star upwards (going roughly over your head) and you will come across a very bright star called Capella. From Capella, you can follow the pentagon of brighter stars nearby that make up Auriga. Just below Capella, there is a triangle of stars known as ‘the kids’ as in goat babies.
Capella was one of the most important stars for navigation as it could be seen throughout most of the year from mid northern latitudes.
Finding the Twins Castor and Pollux
Follow a line from Rigel to Betelgeuse heading upwards and overhead. You will come to two rough sticks of stars that are headed by two brighter stars. This is the constellation Gemini, composed of the twins Pollux and Castor. Pollux is on the left and Castor is on the right.
Method 1: Using the Winter Hexagon Centered About Orion
If you look in around the sky centered on Orion, you should be able to see a rough hexagon of very bright stars. This is called the Winter Hexagon. Starting at Rigel, if you go counterclockwise by one, you end up at Aldebaran in Taurus. Go counterclockwise once more and you end up at Capella in Auriga. Go counterclockwise once more and you end up at the pair of stars Pollux and Castor in Gemini. Go counterclockwise once more and you end up at Procyon in Canis Minor. Finally, if you go counterclockwise once more you end up at Sirius in Canis Major.
- The winter hexagon v/s the summer hexagon? (heavenswithlamps.wordpress.com)
- Constellations: Origins and Now (heavenswithlamps.wordpress.com)
- What is Starhopping? (heavenswithlamps.wordpress.com)
- Astronomy Outreach for dummies (heavenswithlamps.wordpress.com)
- How to identify stars in the winter sky (boyslife.org)
- My Top 20 Guideposts in the Sky (heavenswithlamps.wordpress.com)
- 100 Guide Posts in the Sky (heavenswithlamps.wordpress.com)
- Asterisms : What? and List (heavenswithlamps.wordpress.com)
- Constellations: Official List (heavenswithlamps.wordpress.com)