NGC 4647 and Messier 60, Dance of Galaxies.
- Constellation: Virgo
- Right Ascension: 12h 43m 32.3s
- Declination: 11° 34′ 55″
- Distance: 56 million ly - 63 million ly
NGC 4647 is an intermediate spiral galaxy, and Messier 60 is elliptical galaxy that are just beginning to interact with each other. The pair of interacting galaxies are cataloged as Arp 116, which is a catalog of interacting galaxies. The pair are a part of the Virgo galaxy cluster.
Annotated image follows.
- Details
- Category: Galaxies
- Telescope: Explore Scientific 127 Refractor
- Camera: ZWO 2600 MM
NGC 5897 (2022)
- Constellation: Libra
- Right Ascension: 15h 17m 24.40s
- Declination: −21° 00′ 36.4″
- Distance: 40,000 ly
NGC 5897 is a globular cluster that is a satellite globular of the Milky Way Galaxy. Forming at or before the formation of our galaxy, they typically range in age of 10-12 billion years old. Age is estimated based on the amount of metal located in the stars, which is considered to be anything other than hydrogen and helium. It's measure of metallicity is measured at -1.9 (Fe/H). NGC 5897 has a low density of stars, and using the Sawyer Concentration class which ranges from 1 to 12 (most to least), it is ranked as a low 11.
- Details
- Category: Globular Clusters
- Telescope: Explore Scientific 127 Refractor
- Camera: ZWO 2600 MM
Draco Dwarf Galaxy
- Constellation: Draco
- Right Ascension: 17h 20m 12.4
- Declination: +57° 54′ 55″
- Distance: 260,000 ly
A bit difficult to see, it was only noticed in 1954 from Palomar sky survey photographic plates. It is a satellite galaxy of our Milky Way galaxy.
Consisting of mostly old population stars its virtually dust free thus not creating very many new stars.
Annotated image follows.
- Details
- Category: Galaxies
- Telescope: Explore Scientific 127 Refractor
- Camera: ZWO 2600 MM
Baade's Window (2022)
- Constellation: Sagittarius
- Right Ascension: 18h 03m 32.14s
- Declination: -30d 02m 06.96s
Baade's Window is the largest of 6 relative dust free zones allowing astronomers to study stars in the central bulge of the Milky Way Galaxy. Nothing illustrates the billions of stars in our galaxy like a view of the view of the galactic center, even if only a tiny slice.
Also visible are two globular clusters, NGC 6522 at the center and NGC 6528 below. NGC 6522 is centered in the view of Baade's Window, and at an estimated age of 12 billion years makes it one of the oldest around our galaxy and lies at a distance of 25,100 light years. NGC 6528 is 25,800 light years distant and is unusually meta rich for a globular
The bright star in the lower left is W Sgr, which is a multiple star system, and the primary star is a classical Cepheid variable star that it's magnitude varies over 7 1/2 days.
- Details
- Category: Stars
- Telescope: Explore Scientific 127 Refractor
- Camera: ZWO 2600 MM
Star HD 84406
- Constellation: Ursa Major
- Right Ascension: 09h 47m 30.71
- Declination: +63° 14` 53.3
- Distance: 246 ly
- Apparent Magnitude: 6.94
HD 84406 is located in the constellation of Ursa Major, and a yellow star of spectral type G, and shines at a magnitude of 6.9, just dimmer than a person can see without optical aid.
What is special about HD 84406? Actually not too much as stars go, but that is a good thing as it was used for the initial focusing of the new James Webb space telescope.
Some of the constraints were the star would have to be in the field of view for the telescope for the entire collimation of the mirrors. The star couldn't be too bright which would cause issues with the sensors. Also the star needed to be in an uncrowded area by other stars. And of course the star needs to be stable with a constant magnitude.
- Details
- Category: Stars
- Telescope: GSO RC10
- Camera: ZWO 2600 MM
Trio of Messier Open Clusters
One classification of open clusters is the Trumpler classification. It consists of 3 parameters, the first is the degree of concentration.
I - Detached clusters with strong central concentration.
II - Detached clusters with little central concentration.
III - Detached cluster with no noticeable concentration.
IV - Clusters not well detached, but has a strong field concentration.
The second parameter is the range of brightness.
1 - Most of the cluster stars are nearly the same apparent brightness.
2 - A medium range of brightness between the stars in the cluster.
3 - Cluster is composed of bright and faint stars.
The last parameter categorizes the number of stars in the cluster.
p - Poor clusters with less than 50 stars.
m - Medium rich cluster with 50-100 stars.
r - Rich clusters with over 100 stars.
If the cluster any type of nebulosity, the letter "n" is added to the last parameter.
First up is Messier 34, located in the constellation of Perseus. Consisting of over 100 stars, in a space of a diameter of 14 light years. It is some 1,500 light years distance and shines at an apparent magnitude of 5.5 at an estimated age of 200 million years.
- Details
- Category: Open Clusters
- Telescope: GSO RC10
- Camera: ZWO 2600 MM
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