Sky Watch: The winter stars are coming!

Whenever I spot the constellation Taurus, the bull, rising in the east after dark, I know that winter isn't far behind.

Stargazers with a vivid imagination might be able to trace the stars of Taurus into the outline of a bull's head and long horns, with the bright star Aldebaran marking its fiery red eye.

Aldebaran, along with the bright stars Antares, Regulus and Fomalhaut, was one of the four Royal stars of ancient Persia. Surrounding it, we can easily notice a V-shaped grouping of stars known to astronomers as the Hyades.

In the lore of the ancients -- from Greece all the way to China -- the Hyades has been associated with wet and stormy weather; the name is said to come from an archaic Greek word meaning "to rain."

Only 150 light years away, the Hyades forms the nearest open star cluster to Earth, and may be only about 660 million years old. Though it appears that Aldebaran is part of this cluster, it's actually less than half that distance from us.

Riding on the back of Taurus appears a tiny grouping of stars that many people misidentify as the Little Dipper; it's really a cluster known as the Seven Sisters, so-named because, on a clear dark night, stargazers with excellent vision can see seven stars within it.

Astronomers more properly know it as the Pleiades; the name is believed to derive from the Greek word meaning "to sail" because when ancient stargazers saw the Pleiades rise just before the sun, it was a sign of the opening of the navigational season in the Mediterranean world.

In Greek mythology, the stars represented the half-sisters of the Hyades (the V-shaped star grouping just below the Pleiades) who were saved by Zeus from Orion's pursuit by transforming them into a group of celestial doves. Aratus gave us their individual names in a poem from the third century B.C.:

These the seven names they bear:

Alcyone and Merope, Celaeno,

Taygeta, and Sterope, Electra,

And queenly Maia, small alike and faint,

But by the will of Zeus illustrious all

At morn and evening, since he makes them mark

Summer and winter, harvesting and seed-time

The most famous reference to the Pleiades in English literature, however, occurs in the opening passages of Lord Alfred Tennyson's prophetic "Locksley Hall":

Many a night I saw the Pleiads,

rising thro' the mellow shade,

Glitter like a swarm of fireflies

tangled in a silver braid.

The Pleiades lie less than 400 light-years away, and may be only between 50 and 100 million years old -- a veritable cosmic youngster.

Unfortunately, many modern stargazers live in areas where artificial lights obliterate the faintest stars, and often find it tough to find the Pleiades. But you can almost always spot it by casting your gaze slightly to the side of the cluster; this will make it much more visible than if you stare at it directly.

If you've never seen this magnificent star grouping shimmering in the east after dark, get out this week to do so. It truly is one of the most exquisite sights in all the heavens -- and a true harbinger of the upcoming season.