M45 – The Pleiades, Seven Sisters, Subaru…

M45, also known as the Pleiades throughout the USA, or the Seven Sisters in Greek mythology, or Subaru in Japan, Persian name Soraya, is an open cluster of new – astronomically speaking – stars. This group of stars can be seen with the unaided eye, which is one of the reasons it is so popular among many people, and has been referenced long ago, and also mentioned by Homer around 750 B.C., by biblical Amos around 750 B.C. and by Hesio around 700 B.C. At least 6 of the stars can be seen with the unaided eye, with the number increasing to 9 or so under clear dark skies. On March 4, 1769, Charles Messier added the Pleiades to his list of clusters and nebula published in 1771. It wasn’t until long exposure photography that we realized that the stars of the Pleiades are imbedded in a nebulous material, which are a blue color, which indicates it is a reflection nebula. The brightest of the nebula around Meope was discovered on October 19, 1859 by Ernst Wilhelm Leberecht (Wilhelm) Tempel in Venice. It wasn’t until the later 1880s that the nebulae around Alcyone, Electra, Celaeno and Taygeta were found in photographs.

The nebulae found in the cluster are most likely part of a molecular cloud that is unrelated to the Pleiades star cluster. Many people have believed that the dust in the images is leftover from the formation of the stars, but it does not appear to be associated with the stars due to having different radial velocities. It is calculated that the stars of the Pleiades age is around 100 million years old, with a future lifetime expectancy of another 250 million years. By which time the stars will have spread out onto their own orbital paths. The ESA have determined the distance to the cluster using direct parallax measurements estimating a distance of 380 light-years. Using the Hubble Space Telescope and the Mount Palomar and Mount Wilson Observatories the distance is more accurately estimated to be 440 +/- 6 light-years.

Information from the Messier Catalog

M45 Location

M45 Location

My observations were short that night as it was a bit cold. I didn’t spend more time than I had to outside at the telescope. I did take a couple minutes to soak in the view of the Pleiades. There are no signs of nebula without photography, so even in my telescope it was just bright blue stars arranged in an almost Ursa Minor formation. As a kid I always thought the Pleiades was the little dipper, as it has a shape sort of similar; I believe that may just be due to the way the stars Maia, Electra, Merope, Alcyone, and Atlas form a bowl and handle shape like the dippers.

M45/Pleiades/Seven Sisters/Subaru 12-19-14

M45/Pleiades/Seven Sisters/Subaru 12-19-14

This image is 25 light frames at 5 minutes a piece, 25 Flat Frames, 25 Flat Dark Frames, and 12 Dark Frames. Stacked in a new-to-me software, IRIS and following a tutorial by Jim Solomon’s IRIS Cookbook with some small minor touches in Photoshop.

Equipment:
Omni XLT 150
CG-5 Advanced Series Go-To
PHD Autoguiding
Orion Starshoot Autoguider
Modified Canon 350D
Baader MPCC Mark III Coma Corrector

M52 and NGC 7635 – Open Cluster and Bubble Nebula

Open Cluster, M52, discovered by Charles Messier in 1774, can be found in a rich field of the Milky Way. M52 has been dubbed the name “salt and pepper” cluster. The distance to the cluster is not very well known, but estimates anywhere from 3,000 light years to 7,000 light years, but the Sky Catalogue 2000.0 gives it a distance of 5,200 light years. Estimates are complicated due to higher interstellar absorption the light suffered during its travels toward Earth. Using 5,000 light years as an average the clusters diameter is estimated to be around 13 arc minutes corresponding to a diameter of 19 light years.

The Bubble Nebula, NGC 7635, discovered by William Herschel in 1787, lies in close proximity to the open cluster, M52. The bubble formed from stellar winds from the massively hot central star (SAO 20575 or BD+60°2522) at an 8th magnitude. The nebula itself has an estimated distance of 11,000 light years away with an apparent magnitude of ~10, and a diameter of 15 x 8 arc minutes.

Location of M52 and NGC 7635.

Location of M52 and NGC 7635.

Through the eyepiece from a nice dark location it is easy to make out M52 just fine and count many of the main stars within the cluster without the use of averted vision. The bubble nebula is a little more of a challenge. When I imaged the picture below there was an 88% moon which made it impossible for me to find NGC 7635.

M52 and NGC 7635 – Open Cluster and Bubble Nebula. 08-17-13

This image is 65 x 120 sec light frames, 33 dark frames, 33 flat frames, and 43 bias frames. Taken on the night of August 17, 2013 with an 88% moon washing out a lot of the sky. Image stacked in Deep Sky Stacker and post processing in Photoshop. There were some major editing I had to do in order to clear out noise created from thin clouds on occasion, and the light of the moon making my illumination a bit uneven.

All my Messier Object information from: The Messier Catalog. Screen shot of object location taken in Stellarium. Image stacking in Deep Sky Stacker.

Equipment:
Omni XLT 150 with CG-4 mount
Modded Canon 350D
T-ring and adapter
Intervalometer
Polar Scope for alignment

M36 – Open Cluster

Messier 36 is one of three of the brightest open clusters in the constellation Auriga. Again this cluster was first recorded by Giovanni Batista Hodierna before 1654, and was included in Charles Messier catalog in September 2, 1764. M36 is around 4100 light years distant, with an angular diamter of about 14 light years. The cluster contains 60 proven stars, and the brightest stars have a magnitude of +9 and an overall visual brightness of +6.3. If this cluster were about 10 times closer it would be as bright as the Pleiades.

'X' Marks the Location of M36

‘X’ Marks the Location of M36

Sometimes referred to as the Pinwheel Cluster this small cluster seems to have arms that come out from the central region when viewed through the eyepiece. Many dim stars, but the brighter ones make up the shape for which it is occasionally called.

Open Cluster M36 01-02-13

This image is 12 images at 1 minute a piece, ISO 800, with 14 dark frames. Stacked in Deep Sky Stacker, and processed in Photoshop.

Equipment:
Omni XLT 150 with CG-4 mount
Canon 350D
T-ring and adapter
Intervalometer
Polar Scope for Alignment

M37 – Open Cluster

Well it feels like it has been forever since the last clear night. I was just looking back at previous posts and it has been well over a month since my last night out under the stars. I haven’t done any deep sky imaging since about November 13 and my last imaging of anything was of Jupiter on November 23. Luckily the New Year started off kind with a clear night.

‘X’ Marks the spot of M37

The open cluster M37 in the constellation Auriga was discovered by the Italian astronomer Giovanni Battista Hodierna before 1654, and independently rediscovered by Charles Messier in September 1764. The open cluster is roughly 4500 light-years from Earth with an angular diameter of 24 arcminutes, or 20-25 light-years in diameter. M37 has over 500 stars, 150 of which that are brighter than magnitude 12.5, and about a dozen of or so red giant stars. The estimated age of M37 is around 300 million years.

Through the 25mm eyepiece it was more than just a hazy patch in the sky, some of the brighter stars were easily resolved, but the density of the open cluster made it hard to resolve the dimmer stars making them all seem almost form a slight nebula look to the cluster. With a little bit higher magnification I was able to tell that the cluster had no nebulosity and that the dimmer stars were in fact stars. The color of the stars didn’t shine through the eyepiece, so it was hard to tell how many red giants were within the cluster of mostly blue stars.

M37 Open Cluster in Auriga 01-01-13

This image is a total of 12 one minute images at ISO 800, and 11 dark frames to remove noise. Although an open cluster like this doesn’t need hundreds of images to bring out detail I was unable to get any more images as the cold -15°C temperatures killed the battery after taking a total of 27 images. Hopefully my power supply for my camera will be in the mail in the near future and I wont be limited to the battery’s low tolerance to cold temperatures.

Equipment:
Omni XLT 150 with CG-4 mount
Canon 350D
T-ring
T-ring adapter
Intervalometer
Polar Scope for Alignment

Visiting Some Old Objects

This post is a bit like one of your favorite childhood movies or tv shows being redone, but only better. It’s better because these remakes came out much better than their original versions. Below I have setup a side by side comparison of old and new, and then the new version below it for a comparison, with a click-through link of the original post in the titles.

All of these remakes were all made from the same stacks as the originals; the only thing different is my steps in post processing of the image in Photoshop. The links back to the original pictures have the information on the stacks if you’re curious about how many lights, and dark frames I did.

I did a bit more than just adjusting levels and curves. I took the steps a bit further by adjusting highlights and mid-tones, applying an artificial flat, and adjusted vibrance and hue.

M16 – The Eagle Nebula

M16 – The Eagle Nebula. Before on the Left, After on the Right

M16 – The Eagle Nebula

M20 and M21 – The Trifid Nebula, and Open Cluster

M20 and M21 – Trifid Nebula and Open Cluster. Before on the Left, After on the Right.

M20 and M21 – The Trifid Nebula and Open Cluster

M27 – The Dumbbell Nebula

M27 – The Dumbbell Nebula. Before on the Left, After on the Right

M27 – The Dumbbell Nebula

M33 – Triangulum Galaxy

M33 – The Triangulum Galaxy. Before on the Left, After on the Right.

M33 – The Triangulum Galaxy

M51 – The Whirlpool Galaxy

M51 – The Whirlpool Galaxy. Before on the Left, After on the Right.

M51 – The Whirlpool Galaxy

Look at all the faint galaxies I was able to pop out in view in M51. A few months of editing has come a long way.