Horsehead Nebula

•November 11, 2020 • Comments Off on Horsehead Nebula

One of the fascinating objects in the sky is the Horsehead Nebula, a swirling cloud of gas and dust that obscures the stars behind it. The nebula is located in the Orion Molecular Cloud Complex where star formation is taking place.

First recorded by Scottish astronomer Williamina Fleming on a photgraphic plate taken at Harvard College, E.E. Barnard wrote and early description of the nebula and catalogued it as Barnard 33. An interesting history of the Horsehead Nebula was published in Astronomy magazine last month (October, 2020).

This image was captured remotely using the 24-inch (61cm) operated by the Telescope.live web site at the El Sauce Observatory in the Rio Hurtado Valley in Chile. The image was processed in Pixinsight and Photoshop. The original images consist of four grayscale files captured with luminance (clear), red, green, and blue filters. The grayscale images were combined in Pixinsight to create the color image. Photoshop was used for some noise reduction and to make some minor tweaks and slight crop from the original. The field of view is approximately 30 arc seconds square.

 

 

 

 

Brocchi’s Cluster

•November 1, 2020 • Comments Off on Brocchi’s Cluster

Back in July, I described my beginning efforts to capture the night sky and how I “discovered” this interesting formation of stars in a wide field image taken with my camera. It has gotten to the point where if this is in the field of any image, it jumps right out at me.

But in wide field images, it is a very small object and I wanted a better photo of it. So utilizing the Takahashi 106mm Imaging Platform at the iTelescope.net New Mexico Skies Observatory in Mayhill, NM, I captured this close-up.

The bright formation, referred to as an “asterism”, is superimposed over a background starfield of thousands of distant stars.

The main bright stars of the cluster, also known as “The Coathanger” are mostly luminous blue stars with a couple of red “giants” to fill it out. Conflicting studies over the years have tried to determine this was a true cluster or just a chance alignment of stars. The most recent studies have concluded that it is the latter, based on parallax and proper motion measurements from the Hipparcos satellite.

For more information visit “Brocchi’s Cluster” on Wikipedia.

The “Seven Sisters”

•October 27, 2020 • Comments Off on The “Seven Sisters”

Rising in the east this time of year (October-November) is a hazy area that upon closer examination, if you have excellent eyesight and a good clear atmosphere, is small star cluster dominated by hot, luminous, blue stars formed within the last 75 to 150 million years. That is to say, these stars are, in astronomical time, relatively “young”.

This is the Pleiades cluster otherwise known as the “Seven Sisters”. It apparently got the name because an observer in ancient times could see seven distinct stars, even without any optical aid. It is a challenge to see all seven. The Pleiades are a lovely sight in binoculars or a low power telescope.

Overall, there are over 1,000 members of the cluster, which is The observed nebulosity is due to dust, which is likely an area of dust through which the cluster is moving, rather than the dust being left over form the formation of the stars.

This image was captured through the iTelescope.net web site using the Takahashi 106mm Imaging Platform at the New Mexico Skies Observatory in Mayhill, NM.

Tarantula Nebula in the LMC

•October 26, 2020 • Comments Off on Tarantula Nebula in the LMC

160,000 light years away in the Large Magellanic Cloud is the Tarantula Nebula, which is a vast cloud of gas and dust that is a massive start factory.

It shines a about magnitude 8 and it is the most active star forming region known in the local group of galaxies. The diameter has been estimated between 65,000 and 1,900,000 light years. The nebula and the embedded cluster has an estimated mass of 450,000 times the the sun, suggesting it may eventually develop into a globular cluster of stars.

I captured the image with the 50cm reflector in the El Sauce Observatory situated in the Rio Hurtado valley, Chile , operated by the telescope.live web site. The colors are generated by using narrow band hydrogen alpha, sulphur III, and Oxygen II filtration and processed to the so-called “Hubble pallete”. Each filter was used for four five-minute exposures each for a total of 60 minutes. The image was processed with Pixinsight and Photoshop.

 

The “Silver Coin” Galaxy in Sculptor

•October 4, 2020 • Comments Off on The “Silver Coin” Galaxy in Sculptor

Designated NGC-253, this galaxy is is located at the center of the Sculptor Group in the Sculptor constellation, one of the nearest groups of galaxies to the Milky Way. It is one of the brightest galaxies in the sky even though it has been calculated to be more than 11 million light-years from us. The Sculptor Galaxy can be seen with binoculars and it is considered one of the easiest galaxies to view after the Andromeda Galaxy (M31), although it is 25 degrees south of the equator so it is seen best from the southern hemisphere.

It is known to have a higher than average amount of star formation going on, which is probably supported by a great amount of dust circulating that can be seen in the image.

This image was captured remotely using a telescope at the El Sauce Observatory in Chile through the telescope.live web site.

With my travels being severely restricted due to the coronavirus situation, I have found one satisfying way to pursue photography, even if I have to control the camera remotely.

Southern Neighbor Galaxy: The Large Magellanic Cloud

•September 27, 2020 • Comments Off on Southern Neighbor Galaxy: The Large Magellanic Cloud

The Large Magellanic Cloud is a great cloud of stars in the southern sky, which is named after the explorer Ferdinand Magellan, who wrote about it in his journals. I had the thought recently, after reading about the Large Magellanic Cloud, that Ferdinand and his crew must looked at this this mysterious cloud that spanned the space of more than 21 full moons with a great sense of wonder.

Living in the Northern Hemisphere, we miss some of the most spectacular views of the sky. So when I had the opportunity to capture an image using a the iTelescope.net telescope at the Siding Spring Observatory in Australia, I selected a wide view of the cloud. The LMC is considered a “barred spiral” galaxy although from our view it is difficult to see these characteristics. The observatory in Australia is associated with the iTelescope.net.

The distance to the LMC has been calculatedĀ  to be about 163,000 light years. Its relative closeness has given astronomers many opportunities to study the similarities to and differences from conditions within our own Milky Way. The New General Catalog of Nebulae and Clusters of Stars lists dozens of objects within the LMC. Just the idea that there are distinct objects in another galaxy that are observable is amazing.

Probably the most prominent object is the Tarantula Nebula (NGC 2070) seen in the upper left in the wide-field image above.

The Tarantula Nebula got its name in the mid-20th Century from the appearance in deep photographic exposures. It’s brightness is remarkable given that its distance is on the order of 160,000 light years. I captured this image with the 17-inch Dall-Kirkham telescope at Slooh’s Santa Martian Observatory in Chile.

Interacting Galaxies: The Whirlpool Galaxy M51

•September 21, 2020 • Comments Off on Interacting Galaxies: The Whirlpool Galaxy M51

Some 23 million light-years distant in the constellation Canes Venatici, the Whirlpool Galaxy presents scientists with a wide range of fascinating data. First, there is the interaction with the smaller companion. The interaction was confirmed by signals received by radio telescopes. More details about this fascinating object are in the Wikipedia.

The image was captured remotely using the 17-inch modified Dall-Kirkham telescope at the Slooh.com observatory in the Canary Islands and process with PixInsight and Photoshop. Coaxing the details out of the noisy originals was quite the challenge.

 

 

First Attempt at Narrowband: “Pillars of Creation”

•September 16, 2020 • Comments Off on First Attempt at Narrowband: “Pillars of Creation”

With the remote access to real qualiity teIescopes, I’ve been wanting to try “narrowband” imaging.

Regular color imaging involves red, green, and blue exposures generally along with a fourth exposure with a luminance (black and white) filter. Narrowband imaging uses filters that pass only specific wavelengths that are emitted by gasses consisting of specific chemicals. The most common combinations are Hydrogen Alpha (Ha), Sulphur 2 (Sii), and Oxygen 3 (Oiii). Capturing the emitted light from these three gasses allows analysis of the makeup of a particular cloud of interstellar gas.

The so-called “Pillars of Creation” became famous due to a stunning image from the Hubble Space Telescope. The filtration and processing of the image provided incredible detail and dimension. Even the 100cm instrument in at the El Sauce Observatory in Chile could not equal the Hubble image, but it provided me with some nice raw images that I could process.

The mixing of the colors was done specifically in the “Hubble Pallet”. It was made easier by having a copy of the Hubble image for comparison. It’s not perfect, but I think it’s pretty close.

 

Astrophotography Workflow

•September 4, 2020 • Comments Off on Astrophotography Workflow

This is an image of a huge cloud of gas and dust in the constellation Sagittarius. It is estimated to be 4,000 – 6,000 light-years from us and the size is estimated to be approximately 110 light years across. It reportedly is visible to the naked eye under good sky conditions. It has been named the “Lagoon Nebula”. The nebula is an area of active star formation. For more information, check out the Wikipedia entry.

This image was captured remotely from a telescope in the Canary Islands via the web site slooh.com. Like telescope.live, it is possible to set up “observing” sessions to capture images of objects in space. As mentioned in my previous post, the image files they provide are files that are not readable by Photoshop or any other standard image editor. So my first challenge was to figure out how to process these images.

After some experimentation and research, I have settled on PixInsight. This is a massive (and not inexpensive) software package that has been built to serve the scientific community with an emphasis on astronomy and astrophotography. I am still trying to wade through the many aspects of using the program, hoping I can achieve some competence before the trial period runs out and I have to make the decision to pay for it.

In the previous post I wrote that I would provide more information on how the process works. So …

The basic procedure to capture a color image generates four files taken through red, green, blue, and luminance filters. (Luminance is essentially clear.) They are all grayscale images but since they are captured through different color filters, when the files are combined with the the images assigned to the appropriate RGB and luminance channels the color image is created. That’s where PixInsight comes in.

When first downloaded, the images look like this:

 

 

 

 

 

 

Red, green, blue, and luminance, in order. The first time I saw this, I was worried I had not captured anything! What I eventually realized was, that these cameras provide 16-bit files with a massive dynamic range. In order to bring out the image, it must be “stretched”. The result of initial stretching on the luminance file looks like this:

Each of the four files are stretched and then combined in to one LRGB (Luminance, Red, Green, Blue) file. It is now a color image.

Granted, there is not a lot of color here. So the next step is to save it as a standard .tif file so it can be opened in Photoshop. Once in Photoshop, I adjust the levels (light and dark), boost the color saturation, do some sharpening and noise reduction, which gets to this:

For the final touches, I opened it in Luminar 4, and applied some contrast enhancements and other tweaks. As they say, “season to taste”. The end result is the image at the top of the post.

Telescope: Plane Wave Insruments 17-inch modified Dall-Kirkham design

Focal Length: 2938mm f/6.8

Location: Spain

Camera: Finger Lakes Insruments 4096×4096 pixels

Exposures:

Luminence, Red, Green, Blue; time unknown.

Remote Astrophotography

•August 24, 2020 • Comments Off on Remote Astrophotography

Here is an image that I would loved to have produced using my Olympus camera from my back yard. But aside from the fact that my outfit isn’t capable of this kind of quality, even if it were, the light polluted, hazy skies would make it extremely difficult if not impossible.

While I am still experimenting with the star tracker and the Olympus, I have discovered the world of remote astrophotography, where, for a fee, you can request an “observing” session, or a “mission”, with a telescope typically located at high altitude where the skies are clear, and there is minimal light pollution.

This image was my first effort over the web site telescope.live. They have observatories in Spain, Chile, and Australia. The three locations provide access to the entire sky.

The way it works is that first I decide what I want to photograph (“observe”). I decide which one of the telescopes to use, set the exposure time, filters and other things. The observatory schedules the session (“mission” as it is on one web site”) and then I wait until the image is captured. Once the image is captured, the “data” (files) is transmitted from the observatory, over the Internet, to a server from which I can download them so I can process them.

Therein lies another tale. The first thing I learned that the raw files from the observatory cameras cannot be read by Lightroom, Photoshop, or any of the other standard photo editors. The file format – “.fit” is a format that is very widely used for scientific imaging and has been the standard for digital image output as long as astronomers have been doing digital imaging.

So after setting the parameters for the “observing” request, my contribution to the creation of this image was to take the raw “data” and process it into an image that you can see here on my web site. I’ll describe that process in future posts, but for now, just enjoy looking at one of our nearby neighbors, the Andromeda Galaxy, a mere 2 million lightyears from here.

For my fellow geeks out there …

Telescope: Takahashi 10cm f/3.6 refractor

Location: Spain

Camera: Pixel array 4096×4096

Exposure:

Luminence, Red, Green, Blue; 300 seconds each.

 
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