What are the Seven Sisters? These are stars in the Pleiades star cluster—one of the most noticeable star pattern in the spring. This tiny dipper of six stars appears at nightfall, lowish in the west, directly above where the Sun sets. So, wait, why are they called the Seven Sisters? Read on—plus, find my viewing tips.
According to Greek mythology, these Pleiades were the seven daughters of Atlas, the Titan god who held the sky above. The sisters’ names were Maia, Electra, Alcyone, Taygete, Asterope, Celaeno and Merope. The Greeks weren’t the only ancients to observe and tell legends of the Pleiades. More about this late…
First, where are the Pleiades in the spring night sky? In 2021, mid-April brings a good opportunity to spot this star cluster as the young crescent Moon will be your pointer.
After sunset, look west.
On April 14 and 15, look for the very young crescent Moon. It will hover below the star cluster on the 14th and above the star cluster on the 15th.
The Pleiades look like a small misty dipper of six stars. It’s an obvious sight if you have dark, clear skies.
Here’s another pointer. On the 14th and 15th, the Moon is passing straight between the bright star Aldebarran (on its left or south) and the Pleiades (on its right or north). Aldebarran is the orange eye of Taurus the Bull constellation.
All you need are dark skies and good eyes—or, binoculars!
As Alfred, Lord Tennyson wrote:
Many a night I saw the Pleiades rising thro’ the mellow shade, Glittering like a swarm of fireflies, tangled in a silver braid.
What a poetic image!
Pleiades Legend and Lore
No obstetrician attended the birth of the Pleiades, 120 million years ago. As these fiercely hot suns awakened from the dazzling and dangerous gaseous nursery, the newborn stars materialized like a distant sunrise in the skies of Earth 400 lightyears away.
In ancient times, the Pleiades had a strange sinister reputation. Such medieval rituals as the pagan Black Sabbath and All Hallow’s Eve (which evolved into our own Halloween) were set to occur when the Pleiades reached their highest point at midnight. Some have speculated that the rituals could have originated as a sort of commemoration of some ancient catastrophe that resulted in great loss of life. Some believe they may be linked to the Atlantis myth, itself perhaps a legend evolved from the awesome eruption of the Santorini Volcano in 1450 BC that devastated the Minoan civilization on nearby Crete.
The Pleiades had an odd importance to civilizations throughout time and around the world. In Egypt they were revered as one of the forms of the goddess Isis. In ancient Persia the date in which they reached their highest midnight ascendancy was marked with ceremony. In Mayan and Aztec culture, this same yearly occasion had a forbidding undertone and was given tremendous importance.
Subaru (the Car)
In Japan, their ancient name is Subaru. For decades, the six companies that merged to produce automobiles in 1953 placed a crude star map of the Pleiades on each of their cars. Over the years, one star has been portrayed as brighter and increasingly separated from the others. Does this reveal some cryptic corporate infighting?
The real thrill comes when the proper instrument is pointed their way. Not a giant telescope; that would be a mistake. Far better is a simple pair of binoculars, because low power and wide field are the ticket. Suddenly dozens spring into visibility, and their blue-white color becomes obvious as well. Indeed, this is probably your binocular’s single most amazing celestial vista.
But, to the naked eye, most people count exactly six stars.
So Why Are They Called The Seven Sisters?
Why have civilizations as disparate as the ancient Greeks, Australian aborigines, and Japanese all possessed legends of the “lost Pleiad” which have persisted through the centuries? Even two thousand years ago, a Greek poet wrote:
“… their number seven, though the myths often say … that one has passed away.”
It’s true that most people can only see six stars today (with the unaided eye). However, if you have modern binoculars or a telescope, you may see that seventh star and possibly even an eighth star. Why might these stars by more difficult to see today than in ancient times?
One clue is that, as binoculars reveal, they’re blue—a color that indicates stellar youth. Young hot stars are often unstable, gobbling up their nuclear fuel in an adolescent frenzy that frequently produces instability.
They’re in their infancy even today. And, since such massive stars die young, the Pleiades will be long gone when most of the galaxy’s stars are still enjoying middle age. Toddling gracefully across April’s skies, the newborn sisters are only for now.