M45 Pleiades

M45 Pleiades Mills Rim 8Sep2021
M45 Pleiades; Captured at Mills Canyon, Kiowa National Grasslands, New Mexico, 8 September 2021

Target fun facts

The Pleiades also known as The Seven Sisters, Messier 45 and other names by different cultures, is an asterism and an open star cluster containing middle-aged, hot B-type stars in the northwest of the constellation Taurus. At a distance of about 444 light years, it is among the nearest star clusters to Earth. It is the nearest Messier object to Earth, and is the most obvious cluster to the naked eye in the night sky. It is also observed to house the reflection nebula NGC 1432, an HII region.

The cluster is dominated by hot blue luminous stars that have formed within the last 100 million years. Reflection nebulae around the brightest stars were once thought to be left over material from their formation, but are now considered likely to be an unrelated dust cloud in the interstellar medium through which the stars are currently passing. This dust cloud is estimated to be moving at a speed of approximately 18 km/s relative to the stars in the cluster.

Computer simulations have shown that the Pleiades were probably formed from a compact configuration that resembled the Orion Nebula. Astronomers estimate that the cluster will survive for about another 250 million years, after which it will disperse due to gravitational interactions with its galactic neighborhood.

Together with the open star cluster of the Hyades, the Pleiades form the Golden Gate of the Ecliptic.

The name of the Pleiades comes from Ancient Greek: Πλειάδες. It probably derives from plein (“to sail”) because of the cluster’s importance in delimiting the sailing season in the Mediterranean Sea: “the season of navigation began with their heliacal rising”. However, in mythology the name was used for the Pleiades, seven divine sisters, the name supposedly deriving from that of their mother Pleione and effectively meaning “daughters of Pleione”. The nine brightest stars of the Pleiades are named for the Seven Sisters of Greek mythology: Sterope, Merope, Electra, Maia, Taygeta, Celaeno, and Alcyone, along with their parents Atlas and Pleione. As daughters of Atlas, the Hyades were sisters of the Pleiades. In reality, the name of the star cluster almost certainly came first, and Pleione was invented to explain it.

Other Catalog Designations: Seven Sisters, M45, Cr 42, Mel 22
Subtype: Open Star Cluster
Distance from Earth: 444 light years
Constellation: Taurus

{From: https://en.wikipedia.org/wiki/Pleiades }

Capture Notes

Captured with Big Bertha and the Canon EOS Ra from the dark skies of Mills Canyon, Kiowa National Grasslands, New Mexico.


Polar alignment: QHYCCD camera (controlled by Polemaster)
Imaging stream: Orion 8″ f/8 Ritchey-Chretien Astrograph Telescope, Canon EOS Ra
Mount: Sky-Watcher EQ6-R Pro Equatorial Mount (controlled by EQMOD)
Autoguider: Orion 60mm Multi-Use Guide Scope, Orion StarShoot AutoGuider Pro Mono Astrophotography Camera (controlled by PHD2)
All equipment controlled by HP Probook running Sequence Generator Pro v3.2.0.660.

Capture & processing notes

Sequence plan: ISO800, 49x60sec + 50x180sec + 20x300sec

Capture: 8 September 2021
Shooting location: Mills Canyon, Kiowa National Grasslands, New Mexico
Processing: Stacked in Deep Sky Stacker (DSS), processed in LR/PS.