Thursday, January 29, 2009

Kids, More Kids, and Something Fishy

Last week we located the constellation of Auriga the Charioteer and explored its central asterism (recognizable star pattern), the Pentagon.

Now let’s take a closer look and see if we can spot three smaller, quirkier asterisms.

Auriga the Charioteer in Johann Bode’s 1801 star atlas
Courtesy of
Linda Hall Library of Science, Engineering and Technology

1) About an hour after sunset, locate the Pentagon. Consult last week’s post if you need help finding it.

The Pentagon of Auriga
Star maps created with
Your Sky

2) Just south of bright Capella is a small triangle of stars. This is the asterism known as the Kids, a reference to the two baby goats being cradled by the ancient figure of the Charioteer. The three stars are all dimmer than any of the five stars of the Pentagon.

The brightest of the three is Almaaz, which is Arabic for he-goat. (Do you recall which star in Auriga has a name that means she-goat?) Almaaz is a yellow-white supergiant that undoubtedly will expire someday in a cataclysmic explosion called a supernova.

The other two dimmer stars of the Kids asterism are called the Haedi, Latin for the kids.

Asterisms in Auriga

3) Hoofing it across the Pentagon, south of Menkalinan, look for another small triangle of stars that resembles the Kids, if the Kids were dimmer and upside down. This is the asterism called the Little Kids.

4) Finally, look inside the Pentagon, down toward its “base.” If you’re in a dark location, free of light pollution, you’ll see an elongated patch of light. This is the combined light from a string of four naked-eye stars plus a couple dimmer ones, and this is the asterism known as the Minnow. Can you see the silvery flash of its scales as it navigates the currents of the Milky Way?

Astronomy Essential: Polaris, the North Star, is NOT the brightest star in the night sky.

Many beginning stargazers have trouble picking out Polaris (poe-LAIR-uss) because they figure the North Star must be really bright and flashy. But on the scale of cosmic bling, it’s not much of a sparkler. In fact, it’s number 48 on the brightest-stars hit parade.

The importance of Polaris lies in its location, not its magnitude of brightness. It lies very close to the North Celestial Pole, the imaginary fixed point in the sky that the Earth’s axis would intersect, were it extended from the North Pole into space. Therefore, if you locate Polaris and face it, you’ll be facing geographic north, also known as true north.

To learn how to locate Polaris using the Big Dipper, visit this post.

By the way, the brightest star in the night sky is Sirius, aka the Dog Star, found in the winter constellation of Canis Major, the Big Dog.