Wednesday, 19 December 2018 14:19

NGC 869 and NGC 884, The Double Cluster

Located in the constellation of Perseus are the two open clusters of NGC 869 and NGC 884. Both are at a distance of around 7,500 light years away. Both are a relative young age of 13 million years. The clusters are separated by a few hundred light years. Each cluster consists 300 to 400 stars with NGC 869 being slightly brighter and more compact.

Published in Open Clusters
Thursday, 13 December 2018 12:12

M45, Color camera version

A clear evening presented a chance to try out a recently acquired one shot color camera. The distinctive and well placed and one of my personal favorite objects,  M45 was selected. The camera used was the ZWO ASI071MC Pro. A 16 megapixel camera with a 4944x3284 pixel array with a relative large pixel size of 4.78, it gives a large field of view with the ED80cft scope. A OSC camera is similar to a dlsr camera, and this sensor is used in some Nikon cameras. A bayer matrix is placed over the sensor, which are tiny color filters, so that each 2x2 cell has 1 red, 2 green and 1 blue pixel from which the color image is created. With my standard monochrome cameras, an external filter is placed in front of the camera and exposures are made through each of the different colored filters. A mono camera tends to be more efficient as all the pixels are recording the same color vs 1 or two with an OSC camera. In addition the mono camera is more flexible in that using filters that pass a narrow band of light that can be used to create what is referred to as narrow band images that highlight certain prominent spectrum, such as the hydrogen alpha emission from ionized hydrogen that is often visible in nebula. What the OSC camera does offer is convenience, the ability to acquire all the colors in one image. Especially useful for faster changing objects where successive images through different filters would show movement or smearing.

This image was taken over two evenings using 120 second exposures.

Published in Open Clusters
Wednesday, 05 December 2018 23:35

The Bubble and the Open Cluster

he Bubble Nebula or NGC 7635 is an hydrogen emission nebula with a bubble structure that is formed by stellar wind from a massive central star. Also in the field of view is the open cluster of Messier 52. M52 is at a distance of 4,600 light years and the Bubble Nebula is a more distant 7,000 to 11,000 light years away.

Published in Nebulas
Thursday, 22 November 2018 17:16

Messier 52

Messier 52 is an open cluster located in Cassiopeia. It contains around 193 members. Its estimated distance is between between 3,000 and 7,000 light years. The differences in distances are due to a large amount of interstellar dust in that direction that varies the brightness by an unknown amount.

Published in Open Clusters
Thursday, 22 November 2018 17:06

M 45 Pleiades 2018

Messier 45 or as it is often called, The Pleiades. The name is possibly derived from ancient Greek word "plein" meaning to sail. It is often called the Seven Sisters as the brightest stars are named for the Greek mythological sisters of Atlas and Pleione, Alcyone, Electra, Maia, Merope, Taygeta, Celaeno, and Asterope or Sterope.

The reflection nebula around the cluster was originally thought to be left over dust from the clusters formation, but due to the age of the cluster, that nebulosity would have been dispersed. It seems it is just passing through an dusty region.

The cluster is an estimated 444 light years away, contains over 1,000 members and a large number of brown dwarf objects. Like most clusters, it will slowly disperse over millions of years. The cluster's age is estimated to be between 75 and 150 million years old.

Published in Open Clusters
Friday, 02 November 2018 12:14

NGC 752

NGC 752 is an open cluster of stars located in Andromeda. Consisting of around 60 members is located 1,300 light years away. Many distant galaxies are scattered through out the the image.

Published in Open Clusters
Wednesday, 31 October 2018 13:08

Messier 39

Open cluster nestled against the background star field of Cygnus. The cluster is composed of about 30 members and is located approximately 1,060 light years away. Estimated age is 278 million years.

Imaged with the ED80cft refractor and Zwo1600 mono camera.

Published in Open Clusters
Thursday, 18 October 2018 13:19

Stock 2

North of the Double Cluster is a sparse open cluster called Stock 2, or sometimes called the Muscle Man Cluster. It is said to resemble a stick man figure flexing their biceps. It contains some 50 stars and is located around 1,000 light years distant.

Imaged with the ED80cft refractor and ZWO 1600 mono camera.

Published in Open Clusters
Thursday, 30 August 2018 23:19

NGC 663

A young open cluster located in Cassiopeia, estimated to contain about 400 members. The cluster contains at least 24 Be type stars which are B class stores that show distinctive hydrogen lines in their spectra and at least five blue stragglers. Also visible are two red super giant stars. Imaged with the ES 127 refractor and Atik 314l+ mono ccd.

Published in Open Clusters
Thursday, 05 July 2018 15:29

Counting Stars in Messier 24

Messier 24 or sometimes called the Small Sagittarius Star Cloud is one of the densest concentrations of stars visible in low power optical instruments. The dense concentration of stars as visible due to a lack of dust obscuring the Milky Way in this area.

This image includes the open cluster NGC 6603 just above the center, and several dark nebula that blot out the stars on the right side of the image. The star cloud lies at a distance of 10,000 to 16,000 light years from us.

Published in Galaxies
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