The Pleiades (or Seven Sisters) form a beautiful star cluster near the constellation Taurus. It is one of the closest stellar clouds to Earth - and perhaps the most beautiful to be seen with the naked eye. For millennia they have inspired folklore around the world, and are now being studied as a recent birthplace for new stars.
Method 1 of 2: In the Northern Hemisphere
Step 1. Look for the Pleiades in autumn and winter
In the northern hemisphere, this star cluster is visible to observers on October nights, disappearing again in April. The best month to find them is November, when they are visible from the dawn at dusk and are at their highest point in the sky.
- In early October, the Pleiades will be visible for a few hours after sunset (the exact time will depend on latitude).
- They will still be visible in late summer and early fall, but only in the middle of the night.
Step 2. Look at the southern sky
The Pleiades reveal themselves in the south after sunset, traveling westward throughout the night. At their peak in November, they soar high into the sky and disappear in the northwest before dawn. In late winter and early spring, they will only be visible for a few hours, traveling east to west along the southernmost part of the sky.
Step 3. Find Orion
Orion the Hunter is one of the most famous and distinguished constellations on the entire celestial map. On a winter night at a more boreal latitude, it will be almost at the southern base, halfway between the horizon and the sky above your head. Find it by its belt, a straight line of three strong stars close together. The nearby red star, Betelgeuse, forms your left shoulder (from the viewer's perspective), while the blue giant Rigel, which is on the other side of the belt, represents your right leg.
Step 4. Follow the belt line to Aldebaran
Observe Orion's belt as an arrow aimed towards the next destination, going left to right across the sky (in most times and places, it will aim northwest). The next bright star in that direction will be another red-orange: Aldebaran. This is an Arabic name meaning "follower", probably given because she follows the Pleiades every night.
- Aldebaran is not perfectly aligned with the belt. Don't try to find it with binoculars, or you'll lose it.
- It usually descends below the horizon in March, or even earlier in places in the far north. If Aldebaran is not visible, try to follow Orion's belt until you reach the Pleiades.
Step 5. Advance towards the Pleiades
Continue to advance with your eyes in the same direction (usually northwest) from the belt of Orion to Aldebaran and beyond. Approaching Aldebaran, you will notice a small cluster of blue stars. These are the Pleiades, also called the Seven Sisters or M45.
- Most people can only discern six stars with the naked eye, or even a bright agglutination if light pollution interferes. On a clear night with good dark-adapted vision, you can see even more than seven stars.
- The Seven Sisters are very close together. From end to end, the cluster is only two-thirds the length of Orion's belt, far inferior to the Little Car and the Big Car (star patterns that novice viewers often confuse them with).
Step 6. Use the Taurus constellation as a guide next time
The red giant Aldebaran, described above, also represents the eye of the constellation of the bull. The Hyads cluster, in turn, forms its chin. By becoming familiar with this constellation, you will be able to have it as a starting point in the search for the Pleiades.
It can be difficult to discern the Taurus constellation at full moon, especially in urban areas
Method 2 of 2: In the Southern Hemisphere
Step 1. Look for the Pleiades in spring and summer
They will be visible from October to April, during the spring and summer months in the southern hemisphere.
Step 2. Face the northern sky
In late November, the Pleiades appear northeast toward sunset and advance west until dawn. As the seasons advance, they start to appear higher in the sky with the appearance of the stars and spend less time visible.
Step 3. Look for a line of bright stars
Orion will be upside down in the southern hemisphere, so some observers like to call it the Cauldron, with Orion's sword representing the upward-pointing handle. Your rim (or belt) will be a trio of bright straight stars. The distinct shape is the starting point for discerning various constellations.
This line will have the red giant Betelgeuse on one side and the blue giant Rigel on the other
Step 4. Follow the left line until you reach Aldebaran
Use it as an arrow pointing diagonally to the left. The next bright star in that direction will be Aldebaran, a red giant. It represents the eye of the Taurus constellation. If the sky is clear and the moon is new, you will see the bull's chin just beside Aldebaran, formed by the cluster of Hyades.
Step 5. Continue until you reach the Pleiades
Continue advancing along the same path from the belt of Orion, and you'll arrive at a light cluster of blue stars. These are the Pleiades, also called the Seven Sisters - although most people can only discern six stars or less, while telescopes see many more. They are an "asterism", a star pattern much smaller than a constellation. By keeping your thumb extended at arm's length, you will measure the clump as approximately twice the width of your nail.
- Use binoculars in place of the telescope. The Pleiades cover a large area, and binoculars have a wider field of view than the telescope.
- When they disappear, the Pleiades still tower above the horizon, but being too close to the sun's line to be visible. Later, in the months of November and December (or May and June, depending on the hemisphere), it is possible to see them around dawn (with difficulty even in clear skies). The first "heliac sunrise" (rising close to the sun) of the year will be linked to spring festivals in some regions of the world.