The Pleiades cluster (Pleiades) is an open cluster in Taurus. The name in the Messier catalog is M45. The Japanese name is Subaru.
It can be observed from autumn to early spring, mainly in winter. You can see a collection of 5–7 stars shining with the naked eye, and when you observe them with binoculars, you can see dozens of pale stars. Since it is an open cluster located at a relatively short distance, it has a unique landscape in which small stars are densely packed in a narrow area. Therefore, it has appeared in many records since ancient times, and constellation myths have been created by each ethnic group.
It was added to No. 45 of the Messier Catalog in 1769. The Messier Catalog was published in three parts, but the M45 is the last object listed in the first catalog.
It is a group of pale (hot) stars at a young age of about 60 million to 100 million years. Due to the fast reaction rate of fusion, the lifetime is expected to be relatively short. The gas that spreads around the stars that make up the cluster shines pale because the interstellar gas, which is not originally related to the stars, reflects the light of the cluster.
Among the stars that make up the Pleiades cluster, the following major bright stars are named after the Greek mythological Pleiades 7 sisters, their parents Atlas and Pleione. See the relevant section for the content of Greek mythology related to the Pleiades cluster.
People with normal eyesight can count 6-7 stars under favorable conditions. There are records that a person with very sharp eyesight saw as many as 25 stars with the naked eye. A long time ago, when I took a questionnaire on TV broadcasting in the UK, 73% said that it was 6-8. Homer wrote six, Tremy seven, Alsufi 5-7, and John Russell seven. With a telescope, the number of stars has increased dramatically, and Galileo is seeing 36 stars.
In the ancient Chinese star chart, which will be described later, there are seven "subaru" that represent Pleiades, and in Japan, there is the name of the six-star (Mutsuraboshi).
You can see it beautifully with binoculars. When the magnification exceeds low with a telescope, the cluster appears to be disorganized, but with a telescope with a diameter of 10 cm, the diffused nebula behind the cluster can be seen. The diffused nebula surrounding the 23rd star was discovered by Tempel in 1859 with a telescope with a diameter of 10 cm. "I can see the bleeding light that I can see when I breathe on the mirror. It is about 35'x 20'and spreads from the south of the 23rd star. I thought it was a new comet, but next It was visible in the same place on that day. " In 1875, Schiaparelli at the Milan Observatory confirmed that the nebula had spread from the 23rd to the 17th and 16th stars. "You can see it at 2 inches, you can't see it at 11 inches, you can't see it at large apertures, but you can see it occasionally, but you can see it well in the viewfinder," Webb said.
Name / Myth
The Pleiades cluster is a collection of bright stars that can be seen with the naked eye, attracting people's interest in various cultures, appearing in the Bible, legends, folk tales, and constellation stories, and has numerous names.
The name of the Pleiades is derived from Greek mythology and refers to the seven Pleiades sisters (Asterope, Melope, Electler, Maia, Taygete, Celaeno, Alcyone) born between the giants Atlas and the Pleione of the Nymph. Pleiades served the goddess Artemis.
Also, the seven sisters of Hyades in Taurus, the daughters of Atlas and Aethra, are the daughters of Atlas and Aethra.