Seven Sisters (Pleiades)

#Cluster

#Messier45, #PMC6

About this object

High in the night sky, the Pleiades, or Seven Sisters, shimmer like a celestial jewel box, captivating stargazers for thousands of years. This dazzling open star cluster, nestled in the constellation Taurus, is located 444 light-years from Earth. Named after the seven daughters of the Titan Atlas in Greek mythology, the Pleiades hold a timeless allure. They have inspired countless legends across cultures, from Greek myths to the Japanese Subaru emblem, which echoes their clustered formation.

Through a telescope, dozens of stars become visible, many surrounded by a faint blue nebulosity—the remnants of the gas and dust from which these young, vibrant stars were born just 100 million years ago. Their brilliance extends beyond mythology and science; for ancient mariners, the Pleiades were celestial beacons, helping to navigate vast oceans long before the advent of modern tools. The cluster's visibility in the sky also marked seasonal changes, guiding agricultural societies in planting and harvesting.

Today, the Pleiades remain a reminder of humanity’s bond with the stars, blending the poetry of mythology, the precision of science, and the practicality of exploration into one of the most cherished sights in the cosmos.

Designations

Standardized Catalogues

Messier 45

PMC Observatory Catalogue

#PMC6

Observations

1. 2024-12-15 at around 01:00 am (+00:00)

2. 2024-12-20 at around 10:30 pm (+00:00)

3. 2025-01-09 at around 10:30 pm (+00:00)

4. 2025-02-01 at around 08:45 pm (+00:00)

5. 2025-02-22 at around 07:15 pm (+00:00)

Location in the sky

Very easy to locate due to its visibility to the naked eye within the Taurus constellation. The closest bright star is Aldebaran.

Photographs

Below image shows the Seven Sisters through the finder scope.

More detail is available through a 32mm eyepiece, which is recommended for f/6 for this star cluster.

The seven bright stars are clearly visible.

The Pleiades under very clear (but light polluted) skies, on February 1st, 2025.

The Pleiades on January 9th, 2025.

Sketch

Below is a sketch showing the approximate position of each of the main stars of the cluster.

The Pleiades is an open star cluster located about 440 light-years from Earth in the constellation Taurus. It is one of the most prominent and visually striking clusters in the night sky, containing over 1,000 stars, though only six or seven are typically visible to the naked eye. The brightest stars in the cluster, such as Alcyone, Maia, and Electra, are massive blue giants, classified as spectral types B and A. These stars are much hotter than our Sun, with temperatures ranging from 10,000 to 20,000 K, which gives the cluster its distinctive blue hue. At around 100 million years old, the stars in the Pleiades are relatively young and still in the process of burning hydrogen in their cores. Due to their high mass, these stars burn through their fuel quickly and have relatively short lifespans. The cluster's stars are also surrounded by a faint reflection nebula, a cloud of gas and dust that reflects the light from the stars, giving the Pleiades its signature misty appearance. The Pleiades is not just an aesthetic marvel but also an important object for scientific study. Its proximity allows astronomers to study the evolution of massive stars and their impact on the surrounding interstellar medium. By examining the stars and the reflection nebula, scientists can gain insights into the formation of stars and how they interact with the gas and dust around them.