You can find the Pleiades star cluster – sometimes called the Seven Sisters – easily just by looking for it. No other pattern in the sky is so little and yet so clearly shaped like a dipper. Late at night on September 13, 2014, until dawn on September 14, you can see the waning gibbous moon near this star cluster. The bright reddish star nearby is called Aldebaran.
From the Northern Hemisphere: Look for the moon and Pleiades up in the east late evening or around midnight, or high in the south at or near dawn.
From the Southern Hemisphere: The moon and Pleiades rise after midnight and are found in the northern sky around dawn.
The Pleiades isn’t a constellation. Instead, it’s a cluster of stars. This little cluster is part of the constellation Taurus the Bull. It looks like a tiny misty dipper in the night sky. It’s much more dipper-like than the actual Little Dipper in the northern sky.
In the vast space of our galaxy, the Pleiades are considered to be sibling stars.
Modern astronomers say the Pleiades stars were born from the same cloud of gas and dust some 100 million years ago. This gravitationally bound cluster of several hundred stars looms some 430 light-years distant, and these stars drift through space together at about 25 miles per second. Many of these Pleiades stars shine hundreds of times more brightly than our sun.
So watch before bedtime on September 13, or on September 14 before dawn, for the moon and Pleiades. Because of the moonlit glare, you might need binoculars to view this cluster.
More than one person has asked us about a winking star in the Pleiades. All faint stars are likely to wink out when you look directly at them. The reason is that the light sensitive rods in your eye are found mostly in the outer part of the retina of the eye. That’s in contrast to the color-sensitive cones, which are found mostly in the center of the retina.
So when we look directly at something (as we do most of the time), we’re using the part of our eye that is most sensitive to color. But when we look at something indirectly, looking to one side of it rather than directly at it, we’re using the part of our eye that’s most sensitive to faint light.
It’s an old trick in astronomy never to look directly at faint objects. If you look to one side, you can see faint objects better. Astronomers call this trick using your averted vision.
Bottom line: Watch for the waning gibbous moon and Pleiades star cluster before bedtime this Monday night (September 13, 2014) until Tuesday dawn. You might need binoculars to see the Pleiades in the moon’s glare. When the moon has moved away, you can use the famous constellation Orion to find the Pleiades.