I shot a few subs of the deceptively small Crab Nebula (Messier 1) last night before realizing that the seeing just wasn’t where it needed to be for me to get that target under my belt. It will have to wait for another time. So, after calling that audible and knowing that I had let my focuser gravity drift the night before on my Flame attempt, I decided to grab a few more subs and see what happened when I integrated both nights (which I had never tried previously). The result was about 2.7 hours worth of data that looked like a train wreck when I stacked it, but after cropping off the tattered edges, there was some good in the middle… even if still out of focus. Live and learn. I will definitely put more time into this DSO in the future!
The Flame Nebula (NGC 2024) is an emission nebula in the constellation Orion. It is about 900 to 1,500 light-years away. The bright star Alnitak, the easternmost star in the Belt of Orion, shines energetic ultraviolet light into the Flame and this knocks electrons away from the great clouds of hydrogen gas that reside there. Much of the glow results when the electrons and ionized hydrogen recombine. Additional dark gas and dust lies in front of the bright part of the nebula and this is what causes the dark network that appears in the center of the glowing gas. The Flame Nebula is part of the Orion Molecular Cloud Complex, a star-forming region that includes the famous Horsehead Nebula (Barnard 33). It is one of the most identifiable nebulae because of the shape of its swirling cloud of dark dust and gases, which bears some resemblance to a horse’s head when viewed from Earth. This stellar nursery, as it is known, can contain over 100 known organic and inorganic gases as well as dust consisting of large and complex organic molecules. The red or pinkish glow originates from hydrogen gas predominantly behind the nebula, ionized by the nearby bright star Sigma Orionis. Magnetic fields channel the gases leaving the nebula into streams, shown as streaks in the background glow. A glowing strip of hydrogen gas marks the edge of the massive cloud and the densities of stars are noticeably different on either side. The heavy concentrations of dust in the Horsehead Nebula region and neighboring Orion Nebula are localized, resulting in alternating sections of nearly complete opacity and transparency. The darkness of the Horsehead is caused mostly by thick dust blocking the light of stars behind it. The lower part of the Horsehead’s neck casts a shadow to the left. The visible dark nebula emerging from the gaseous complex is an active site of the formation of “low-mass” stars. Bright spots in the Horsehead Nebula’s base are young stars just in the process of forming.
This is a very short 5x180s integration with no noise reduction applied. I want to come back to this target when I have some time to spend with it. It is much brighter than I expected!
Messier 16, the Eagle Nebula (NGC 6611), is a young open cluster of stars in the constellation Serpens. The Eagle Nebula is part of a diffuse emission nebula. It contains several active star-forming gas and dust regions, including the famous “Pillars of Creation” region. This region of active current star formation is about 7000 light-years from us and the tower of gas that can be seen coming off the nebula is approximately 9.5 light-years or about 90 trillion kilometers long.
Back to back nights with new moon darkness have been a real treat. I learned a lot… like not to try and clean my sensor when there is a caliche road anywhere within 500 miles and that you can never check your focus too often. This image of the Eastern Veil nebula suffers from some focus drift because I didn’t have everything nice and snug on my Crayford. Some of the images from this weekend are plagued by the mound of dust I introduced into my sensor. I started dithering for the first time. I am getting better at using FWHM (full width half maximum) focus… especially after losing hours of data to my inattention to this gremlin. Overall, it was just great to be out under the stars and feeling like I’m making progress. I’m grateful.
The Veil Nebula is a cloud of heated and ionized gas and dust in the constellation Cygnus. It constitutes the visible portions of the Cygnus Loop, a large but relatively faint supernova remnant. The source supernova exploded some 5,000 to 8,000 years ago, and the remnants have since expanded to cover an area roughly 3 degrees in diameter (about 6 times the diameter, or 36 times the area, of the full moon). The distance to the nebula is not precisely known, but Far Ultraviolet Spectroscopic Explorer (FUSE) data supports a distance of about 1,470 light-years. The analysis of the emissions from the nebula indicate the presence of oxygen, sulfur, and hydrogen. This is also one of the largest, brightest features in the x-ray sky. This particular image is of the Eastern Veil (also known as Caldwell 33), whose brightest area is NGC 6992, trailing off farther south into NGC 6995 and IC 1340.
The Helix Nebula (NGC 7293) is a large planetary nebula located in the constellation Aquarius about 700 light-years away and spans about 2.5 light-years. Gases from the star in the surrounding space appear, from our vantage point, as if we are looking down a helix structure. The remnant central stellar core, known as a planetary nebula nucleus or PNN, is destined to become a white dwarf star. The observed glow of the central star is so energetic that it causes the previously expelled gases to brightly fluoresce.
Sweet, dark skies. Last night was my very first imaging session during a new moon and the skies were glorious… well, relative to normal for this neck of the woods.
I’ve been wanting to shoot the Bubble Nebula for some time now. I know I’ll come back to this target after I get some better Ha response in my imaging rig, but here is a short integration first attempt with poor tracking. I opted to not crop out Messier 52 because it gives a neat perspective.
The Bubble Nebula (NGC 7635) is a Hydrogen emission nebula in the constellation Cassiopeia. The “bubble” is created by the stellar wind from a massive hot central star about 10 to 40 times larger than our own. The nebula is near a giant molecular cloud which contains the expansion of the bubble nebula while itself being excited by the hot central star, causing it to glow. It was discovered in 1787 by William Herschel. You can also see Cassiopeia’s open cluster, Messier 52 (NGC 7654), in the upper right of the photo.
I made the 115 mile round trip to my closest dark site last night. I didn’t realize until after I was done polar aligning and taking flats that the local university had a lab scheduled for the facility. Over the hours of dusk and the beginning of nightfall, dozens of students were driving in with every form of light known to man blasting from their vehicles. I shot dark subs while this was going on and enjoyed some java and a gorgeous sky whilst kicking myself for leaving my binoculars at home. Once things settled down and the gaggle of them were doing their thing around the grounds, I started imaging. The low-pass filter in my unmodded DSLR makes red band targets challenging unless you are going to sink a lot of integration into them, so I decided to try something… well, not red. This is my first attempt at the Iris, but definitely not my last since this is such a cool DSO. I did the integration early this morning in a hurry, so I’ll likely go back and redo all the post processing to try and take care of some more of the noise issues when I have time to focus on it. At any rate, it was a wonderful night out despite the lingering headlights and faint murmur of “like, ermagerd, <insert pop-culture drama>, like, I know, right, like” on the wind.
The Iris Nebula (NGC 7023) is a bright nebula in the constellation Cepheus. NGC 7023 is actually the cluster within the nebula, but everyone kinda lumps it all together in colloquialism. It livies about 1,300 light-years away and is six light-years across. There are four main flavors of nebulae: reflection, dark, planetary, and emission. The etymological root of “nebula” means “cloud”. This one happens to be a reflection nebula… which means the energy from the nearby stars is insufficient to ionize the gas of the nebula to create an emission nebula, but is enough to give sufficient scattering to make the dust visible. The main star lighting this puppy up is SAO 19158.
The CSC looked awesome last night despite the moon phase, so I went out for another run at some targets… and practice. I arrived early enough to take flats while I unloaded the rest of my gear and then shot bias frames while I was balancing and doing my polar alignment. The sky was very clear and the visibility was far above average for where I image. The only issue was the moonlight from being about 70% full phase (waxing gibbous).
I was having some trouble finding targets bright enough to image. I blame my ignorance of the night sky for most of that, but the ambient light definitely was part of it. I even had a difficult time with star alignment due to the diminished relative brightness of the alignment stars. Eventually, I shot a few lights and darks of M92 – because it is very bright – just to have something to process, but over the course of a few hours, I tried several targets with no result. I even realigned my mount thinking I surely must be slewing off target. Nope and nope. The night grew colder and even though I was running my dew heaters, I didn’t have them set high enough to prevent moisture from forming on the front element. I will pack a hair dryer for times like this moving forward so I can do a quick recovery.
As the moon moved toward setting, the promise of amazing imaging was near, but I was cold, hungry, frustrated, and out of coffee… all with another hour and a half until moonset. I decided to just pack it in. It was a good learning experience and another night of practicing set up, balance, alignment, acquisition, and tear down of my gear. Practice is good.
When I decided to jump into this hobby, there were two targets I knew that I knew that I knew I wanted to start with: the Andromeda Galaxy and the Great Orion Nebula. Not only are they two of the brightest deep space “objects” in the night sky, but they are also quite large and fairly easy to reach with modest equipment. By the time I read some books, joined some clubs, did some research, and decided what to buy to start this journey, both these amazing targets had slipped away from my grasp for the summer. Only now, as we enter fall, are they coming back around and giving me a chance to gaze upon them and scoop up some photons. I think it is ridiculously cool that you can see these with your bare eyes on a clear night. Here is my first attempt at M42 working in collaboration with my AP buddy, Dave.