Caption
The stunning Pleiades, photographed on April 1, 2019, by Abhijit Patil. (See more at abhijitpatilphoto.com and @abhijitcpatilphotography on Instagram).
The Seven Sisters, also known as the Pleiades star cluster, form one of the most recognizable patterns in the night sky. This sparkling group of stars, sometimes called a “tiny dipper,” is a favorite sight on fall and winter evenings. But why are they called the Seven Sisters when many people see only six stars? Let’s explore the astronomy, mythology, and meaning of this famous star cluster.
Why Is the Pleiades Star Cluster Called the Seven Sisters?
The Seven Sisters come from Greek mythology. The Pleiades were the seven daughters of Atlas, the Titan who held up the sky, and the Oceanid nymph Pleione. The sisters have names: Alcyone, Asterope, Electra, Celaeno, Maia, Merope, and Taygete.
In the sky, the Pleiades are an open star cluster—a group of stars born together—in the constellation Taurus, the Bull. Although only a handful stand out to the unaided eye, the cluster contains many more stars.
Wen Can You See the Pleiades?
For Northern Hemisphere observers, fall and winter are excellent seasons to enjoy the Pleiades. Look toward the east on fall evenings as the cluster climbs into view. By winter, it is higher in the evening sky; by spring, it appears in the west after sunset.
Despite their dipper-like shape, these stars are not the Little Dipper. Look for a small, tightly packed gathering that may appear slightly fuzzy at first. NASA describes the unaided-eye view as a grouping of six or seven stars.
How Old Are the Pleiades?
No obstetrician attended the birth of the Pleiades, roughly 100 million years ago. As these fiercely hot suns awakened in their gaseous nursery, the newborn stars began the lives we now glimpse from about 440 light-years away. Estimates vary, but the cluster is generally placed at roughly 100 to 125 million years old—still young by stellar standards.
Their brightest blue-white stars lend the cluster its sparkling appearance. But those brilliant stars are only part of the family: Fainter, lower-mass stars belong to the Pleiades, too.
Pleiades Meaning and Symbolism
The Pleiades have inspired stories and helped people mark the seasons in cultures around the world. Their meaning, however, differs from one tradition to another.
In Greek mythology, they are seven sisters. In Māori traditions, the cluster is known as Matariki, and its appearance before dawn in midwinter marks the new year for many communities. Different iwi recognize and celebrate this seasonal marker in different ways.
Some researchers have also proposed that dots painted near a bull in France’s Lascaux cave represent the Pleiades. It is an intriguing interpretation, rather than established proof that the paintings depict this star cluster.
The Pleiades and the Subaru Connection
In Japan, the cluster is known as Subaru. If the name sounds familiar, look at the badge on a Subaru automobile: Its six stars were inspired by the Pleiades.
The name also conveys the idea of coming together—a fitting choice for the company formed when five Japanese companies merged to create Fuji Heavy Industries in 1953.
Why Can We See Only Six Stars in the Seven Sisters?
Despite the name, there is no fixed number that everyone can see. Many observers notice six stars; others pick out seven or more. Eyesight and observing conditions affect the view.
The “missing sister” has inspired both stories and scientific speculation. One proposed explanation concerns the close pairing of Atlas and Pleione, whose light can blend together to the unaided eye. Researchers have suggested that their changing separation over very long periods might help explain some seven-star traditions, but this remains a hypothesis.
You don’t need to solve the mystery to enjoy the view. Find a dark spot, let your eyes adjust, and see how many you can count.
Viewing the Pleiades Through Binoculars
The real thrill comes when the proper instrument is pointed their way. A simple pair of binoculars is an excellent choice because low power and a wide field are the ticket.
Suddenly, many more stars spring into visibility. A telescope can offer a beautiful view, too, provided its field is wide enough to frame the cluster. Indeed, this may be one of your binoculars’ most amazing celestial vistas.
Young by stellar standards, the sisters continue their graceful journey across our skies. On the next clear evening, take a look—and count them for yourself.
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