lucadinoi1988
Pleiadi Apo
The Pleiades (also known as the Seven Sisters, the Little Hen, or by the acronym M45 in Charles Messier's catalog) is an open cluster visible in the constellation of Taurus. This cluster is quite close (440 light years) and has several stars visible to the naked eye. In urban environments, only four or five of the brightest stars can be seen, in a darker place even twelve. All the components are surrounded by light reflection nebulae, observable especially in long exposure photographs taken with telescopes of considerable size.
It is noteworthy that the stars of the Pleiades are really close to each other, have a common origin and are linked by gravity.
Given their distance, the stars visible between the Pleiades are much hotter than normal, and this is reflected in their color: they are blue or white giants; the cluster actually has hundreds of other stars, many of which are too far away and cold to be seen with the naked eye. The Pleiades are a young cluster, with an estimated age of about 100 million years and a predicted life of only another 250 million years, since the stars are too far apart.
Because of their brightness and proximity to each other, the brightest stars of the Pleiades have been known since ancient times: they are mentioned, for example, by Homer and Ptolemy. The Nebra disk, a bronze artifact from 1600 BC found in the summer of 1999 in Nebra, Germany, is one of the oldest known representations of the cosmos: in this disk the Pleiades are the third clearly distinguishable celestial object after the Sun and the Moon.
Since it was discovered that stars are celestial bodies similar to the Sun, it was hypothesized that some were somehow linked to each other. Thanks to the study of proper motion and the scientific determination of the distances of the stars, it became clear that the Pleiades are indeed gravitationally linked and that they have a common origin.
The Pleiades cluster is located north of the celestial equator, therefore in the Northern Hemisphere; its declination is about 24°N, so it is close enough to the celestial equator to be observable from all populated areas of the Earth, up to the Antarctic Circle. North of the Arctic Circle they appear circumpolar, while one degree north of the Tropic of Cancer they can be observed at the zenith. In the Northern Hemisphere the cluster dominates the evening sky from mid-autumn to early spring, in the Southern Hemisphere it is typical of the summer sky.
9 hours of shooting with a color camera, l-pro filter and apochromatic triplet
Pleiadi Apo
The Pleiades (also known as the Seven Sisters, the Little Hen, or by the acronym M45 in Charles Messier's catalog) is an open cluster visible in the constellation of Taurus. This cluster is quite close (440 light years) and has several stars visible to the naked eye. In urban environments, only four or five of the brightest stars can be seen, in a darker place even twelve. All the components are surrounded by light reflection nebulae, observable especially in long exposure photographs taken with telescopes of considerable size.
It is noteworthy that the stars of the Pleiades are really close to each other, have a common origin and are linked by gravity.
Given their distance, the stars visible between the Pleiades are much hotter than normal, and this is reflected in their color: they are blue or white giants; the cluster actually has hundreds of other stars, many of which are too far away and cold to be seen with the naked eye. The Pleiades are a young cluster, with an estimated age of about 100 million years and a predicted life of only another 250 million years, since the stars are too far apart.
Because of their brightness and proximity to each other, the brightest stars of the Pleiades have been known since ancient times: they are mentioned, for example, by Homer and Ptolemy. The Nebra disk, a bronze artifact from 1600 BC found in the summer of 1999 in Nebra, Germany, is one of the oldest known representations of the cosmos: in this disk the Pleiades are the third clearly distinguishable celestial object after the Sun and the Moon.
Since it was discovered that stars are celestial bodies similar to the Sun, it was hypothesized that some were somehow linked to each other. Thanks to the study of proper motion and the scientific determination of the distances of the stars, it became clear that the Pleiades are indeed gravitationally linked and that they have a common origin.
The Pleiades cluster is located north of the celestial equator, therefore in the Northern Hemisphere; its declination is about 24°N, so it is close enough to the celestial equator to be observable from all populated areas of the Earth, up to the Antarctic Circle. North of the Arctic Circle they appear circumpolar, while one degree north of the Tropic of Cancer they can be observed at the zenith. In the Northern Hemisphere the cluster dominates the evening sky from mid-autumn to early spring, in the Southern Hemisphere it is typical of the summer sky.
9 hours of shooting with a color camera, l-pro filter and apochromatic triplet