night sky

Featured constellations: Gemini the Twins, Auriga the Charioteer, and Canis Minor

For thousands of years, humans have looked up at the stars. The stars helped them try to understand their purpose, and the role they play in our lives.

To help memorize the different stars, patterns of connect-the-dot figures were created by many different cultures. Today, we recognize 88 official patterns or “constellations” of stars.

In last month’s blog, we discussed Orion the Hunter, as well as a number of other prominent constellations seen in the winter.

This month’s post will focus on three others, most notable Gemini the Twins.

Gemini the Twins

gemini-constellation

High overhead is the constellation of Gemini the Twins. Unlike many constellations, Gemini really looks like what it is supposed to be – twin people. The constellation is a pair of stick figures “Castor” and “Pollux.” Each figure is named for the brightest star at its head. To remember which is which, remember that the star Castor is closer to Polaris, the North Star, than his brother Pollux.

The star Pollux was one of the first discovered to be harbouring an extrasolar planet (2006) – a planet beyond our solar system. Now, thanks to various methods including the orbiting Kepler spacecraft, we know of thousands of extrasolar planets.

Pollux’s brother star, Castor, is a remarkable star. Astronomers have found that nearly half of all stars have companions. While most of these companion groupings occur as double stars (two stars in orbit around one another) Castor actually is made up of three pairs of double stars (six stars in total). Unfortunately, most of the six stars are too close together for us to observe without a special telescope.

The body of Castor extends downwards to its giant foot. Looking above its toe in binoculars, one can find an open cluster; a loose grouping of stars that have all formed together from a giant gas cloud. While the cloud may have dissipated, the leftover stars can still be seen.

Auriga the Charioteer

gemini-constellation

To the right of Gemini the Twins lies the constellation of Auriga, the Charioteer. Unlike its neighbour, seeing a charioteer here requires a tremendous amount of creative imagination. However, if you stretch your perspective a bit, you’ll see a house with a base, two walls ,and a three-pointed roof.

The brightest star in Auriga is Capella. This star is one of the brightest stars in the winter sky, though it can also be seen rising around midnight during the summer. Many a time a camper who stays up past midnight in the summertime will note a bright twinkling object rising in the east. That star is Capella.
Within Auriga, towards its left (east) side are three more open star clusters, each similar to the one found in Gemini.

Canis Minor, the Lesser Dog

Rounding out our three February constellations is Canis Minor, the Lesser Dog. The brightest star in this very small constellation is Procyon, which means “before the dog” because it rises before the bright dog star – Sirius.

To learn more about February’s astronomy, visit our Eyes on the Skies post.