The Hyades cluster is located 153 light-years away in the constellation Taurus, making it the closest open cluster to Earth. This beautiful arrangement of stars has fascinated stargazers since ancient times and is one of the most intensely studied clusters in the entire sky. It also contains several hundred stars that all originated at about the same time, have similar chemical compositions, and share a common proper motion across the sky.
In 2006, one of the Hyades’ brightest stars, Epsilon Tauri (Ain), was found to host a giant gas planet, making it the first planet to be found in an open cluster.
Let’s explore some more fascinating facts about the Hyades.
Quick Hyades Facts
- Constellation: Taurus
- Coordinates: RA 4h 27m |Dec. +15° 52″
- Distance: 153 light-years
- Object type: Open star cluster
- Diameter: 17 light-years
- Apparent magnitude: 0.5
- Age: 625 million years
- Other designations: Melotte 25, Collinder 50, Caldwell 41
1. Locating the Hyades
Locating the Hyades cluster in the night sky is relatively straightforward. Look for the constellation Taurus, which is one of the prominent constellations of the winter sky in the Northern Hemisphere. Within Taurus, you’ll notice a prominent V-shaped cluster of stars. This V-shaped pattern represents the head and horns of a bull, with the Hyades cluster positioned at the center of the V. The brightest star in this cluster is Aldebaran, a red-orange star that marks the “eye” of the bull.
2. Best Seen
The Hyades cluster is visible during the autumn and winter time from the northern hemisphere, although best seen at about 9 PM Local Time during the month of January, when it is highest in the sky.
- Late Autumn (November): The Hyades cluster begins to rise in the eastern sky during the early evening hours, becoming more prominent as the night progresses.
- Winter (December to February): This is the optimal time to observe the Hyades cluster. Taurus, with its distinctive V-shaped pattern, is high in the sky during the evening hours, making it easy to locate the cluster. In December, Taurus rises in the east shortly after sunset, reaching its highest point in the sky around midnight.
- Early Spring (March): While Taurus and the Hyades are still visible in the evening sky during March, they begin to set earlier as spring progresses. Observing conditions may vary depending on your location and local weather conditions.
3. Star Types
The Hyades cluster contains around 500+ stars, at least 20 of which can be seen in its “V” shape formation, rising to more than 100 with good-sized binoculars. The majority of stars in the Hyades cluster are white or blue main sequence stars, which add to the cluster’s brilliance. Other star types in this cluster include red giants, binary and multiple star systems, and some failed stars known as brown dwarfs. Aldebaran, the brightest star visible in this cluster, is not actually a member of the Hyades. Located just 65 light-years distant, Aldebaran is merely a foreground star that lies along the same line of sight as the main cluster.
4. Age
The Hyades cluster stars formed together from the same giant molecular cloud, resulting in their close proximity to one another in space. The cluster’s stars vary in age, with estimates ranging from 625 to 725 million years old.
Another notable aspect of the Hyades cluster is that it has far outlived the time it takes typical open clusters to disperse. While most open clusters typically disperse within 50 million years or so after the formation of the cluster has ended, the Hyades’ distance from the galactic core has largely prevented the process known as “evaporation”, in which stars are tidally stripped from the cluster. However, a large percentage (about 30%) of the cluster’s members are now at, or close to the tidal radius, and it is expected that the Milky Way will completely disrupt the cluster over the next few hundred million years.
5. Hyades Myth and History
The Hyades have a rich history dating back to ancient times. They were known to many ancient civilizations, including the Greeks, who mentioned them in their mythology. In Greek mythology, the Hyades were the daughters of Atlas and half-sisters of the Pleiades. According to legend, they were transformed into stars by Zeus to honor their mourning for their brother, Hyas, after he was killed by a lion or wild boar while hunting.
According to ancient traditions, the Hyades are associated with wet and stormy weather, with the tears of the Hyades believed to be the cause of the rain. Additionally, their placement in the constellation Taurus, which rises in the autumn and is associated with the rainy season in the Mediterranean climate, reinforced their association with rain and stormy weather. While modern astronomy has provided scientific explanations for weather patterns, the mythological association of the Hyades with rain and storms continues to resonate in cultural and literary contexts, preserving the enduring legacy of ancient celestial myths.in gravitationally bound to the cluster for extended periods.