Taurus Constellation: Aldebaran, Pleiades, and the Crab

If you could only learn one constellation in the winter sky, Taurus would be a strong choice. It's home to some of the most famous objects in amateur astronomy: the fiery orange star Aldebaran, the glittering Pleiades star cluster, the sprawling Hyades, and the ghostly remains of an ancient supernova, the Crab Nebula. You get a lot of sky in one constellation.

Finding Taurus

Taurus is a winter constellation, best visible from November through March in the Northern Hemisphere. Finding it is straightforward if you know Orion:

1. Locate Orion's Belt, those three stars in a row are one of the easiest patterns in the sky.
2. Follow the belt to the upper right (northwest). The first bright star you hit is Aldebaran, the eye of the bull.
3. Continue past Aldebaran and you'll reach the Pleiades, a small, tight cluster that looks like a miniature dipper.

Taurus spans a large area of sky between Orion and Perseus. The bull's face is outlined by the V-shaped Hyades cluster, with Aldebaran at one tip of the V and two long horns extending to the northeast.

Aldebaran: The Eye of the Bull

Aldebaran is a red giant star about 65 light-years from Earth. Its orange-red color is visible to the naked eye, and it's the 14th brightest star in the sky at magnitude +0.85. The name comes from the Arabic for "the follower" because it appears to follow the Pleiades across the sky.

What makes Aldebaran interesting is its size. It's roughly 44 times the diameter of our Sun. If you placed it where the Sun is, its surface would extend almost to the orbit of Mercury. Yet despite its enormous size, it's a relatively cool star, about 3,900 K compared to the Sun's 5,800 K. That lower temperature is what gives it that warm, orange glow.

Aldebaran sits in front of the Hyades cluster from our perspective, but it's not actually a member. The Hyades are about 150 light-years away, while Aldebaran is less than half that distance. It's a line-of-sight coincidence, but a beautiful one.

The Pleiades (M45): A Jewel Box

The Pleiades, also known as the Seven Sisters or Messier 45, is arguably the most famous star cluster in the sky. To the naked eye, most people can see six or seven stars in a tight group. Binoculars reveal dozens more, and a telescope shows hundreds of stars scattered across roughly two degrees of sky.

The cluster is about 444 light-years away and contains over 1,000 confirmed member stars. The brightest ones are hot, blue-white stars only about 100 million years old, young by stellar standards. Long-exposure photographs reveal blue reflection nebulosity surrounding the brightest stars, caused by interstellar dust that happens to lie in the cluster's path.

The Pleiades are best observed with binoculars or a wide-field telescope at low magnification. A narrow field of view at high magnification actually ruins the experience, you lose the sense of the cluster as a whole. This is one of those objects where less magnification gives you more.

The Hyades: The Nearest Open Cluster

The Hyades form the V-shaped face of Taurus and hold the distinction of being the nearest open star cluster to Earth at just 150 light-years. The cluster contains several hundred stars spread across about 20 light-years of space, and they're all moving together through the galaxy, a genuine family of stars born from the same molecular cloud about 625 million years ago.

Because they're so close and well-studied, the Hyades serve as a critical distance calibration point in astronomy. Our understanding of how far away other clusters and stars are is partly built on our precise measurements of the Hyades distance. They're one of the rungs on the cosmic distance ladder.

Observing the Hyades is delightful in binoculars. The V-shape fills the field of view with dozens of stars of varying brightness and subtle color differences. Look for double stars within the cluster, there are several fine pairs.

The Crab Nebula (M1)

Near the tip of the bull's southern horn lies one of the most historically significant objects in the sky: the Crab Nebula, or Messier 1. This is the remnant of a supernova that was observed by Chinese astronomers in 1054 AD. The expanding cloud of debris is still visible today, powered by a rapidly spinning neutron star (pulsar) at its center.

The Crab Nebula requires a telescope to see, it's about magnitude +8.4. In a 6-inch telescope, it appears as a faint, oval smudge about 1 degree northwest of the star Zeta Tauri. Larger telescopes under dark skies reveal hints of its filamentary structure. For a deep dive, see our complete guide to the Crab Nebula.

Other Targets in Taurus

Beyond the marquee objects, Taurus offers several more rewarding targets:

• NGC 1647: A large, loose open cluster about 4 degrees northeast of Aldebaran. Best in binoculars or a wide-field eyepiece.
• NGC 1746: Another open cluster, larger and sparser, about 7 degrees from Aldebaran. A nice binocular sweep target.
• T Tauri: The prototype of an entire class of young, variable stars. T Tauri stars are pre-main-sequence stars still settling down, stellar infants, essentially.
• Hind's Variable Nebula (NGC 1555): A small reflection nebula illuminated by T Tauri. It varies in brightness over years and decades as T Tauri's output changes.

Best Observing Strategy

When you set out to explore Taurus, work from the naked eye inward:

1. Start with the Pleiades, count the stars, then sweep with binoculars.
2. Move to the Hyades, trace the V, enjoy the color contrast with Aldebaran, look for doubles.
3. Switch to a telescope for the Crab Nebula, use Zeta Tauri as your guide star.
4. If you're imaging, the Pleiades reflection nebulosity is a rewarding target that responds well to broadband RGB capture. Check our astrophotography guide for tips.