Sketching Galaxies At The Eyepiece
Galaxies have always been my favourite objects to observe. They provide a new challenge to any observer that you can’t likely find while observing any other type of object in the night sky.
I’ve observed hundreds of these objects and the thing that’s of real importance to every observer is that they’re all different. They’re all host to their own characteristics that make them unique places in the Universe.
B elow you’ll see my sketch of M77, one of the largest, most magnificent and conspicuous galaxies in the Messier catalogue. At sixty million light years away, it’s size is all but twice that of the Milky Way’s. It exhibits several features that you can try and see at the eyepiece and depict on paper.
Before starting your sketch, make sure you have all of the necessary materials available. I like to have a clipboard to write on, pencils with graphite of varying hardness ranging from 2H to 8B, and black gel pens. I started using gel pens after realizing that the penciled-in stars don’t stand out on paper as well as I’d like them to.
Ink is very concentrated, just like the stars are, and dark, meaning things will look better if you ever decide to scan your depictions into the computer to share with others.
Before sketching any target, I like to know what to look for. Determine whether or not it will exhibit a definite nucleus, a complex surrounding star field, spiral arms & what shape they are (not to mention how much of them you may be able to see how large it will be in comparison to the apparent field of views created by the eyepieces you’ll use, and if there are any stars in front of the galaxy itself that may obscure its appearance.
It always helps when sketching to include as many details as you can grasp because it shows any onlooker or viewer what you’re capable of seeing. When peering into the eyepiece, take notice of how large it is, and its orientation (as previously mentioned).
When I started the sketch I began by rubbing some 8B graphite from a pencil on my finger, and then rubbed it into the paper to define the galaxy’s borders against the background.
This is common practice when I’m sketching any target, and I’m sure you would find it useful as well to know the limits of the area you’re allowed to work with.
Next, I took a 4B pencil and drew the very intense nucleus.
Harder graphite doesn’t necessary mean that it’s going to stand out more; any feature will stand out if you press hard enough. It does mean, however, that you won’t be able to smudge it away quite like you would if softer graphite were used.
Next, I checked for the outer region that surrounds the nucleus. It portrayed an uneven distribution of light as well as mottling, so I needed the help of an eraser.
I removed any excess graphite from around the bright center, essentially modeling regions where the surface brightness was too dim for me to detect it. In doing so, I outlined some spiral arm detail. This seclusion from the surrounding area isolates any more-important places that are a part of the galaxy itself.
I’ll then darken any spiral arm detail to make it stand out more. In a ten inch telescope, such as what I used to create the rendition, it’s very possible to detect spiral arms on galaxies.
You just have to know where to look and concentrate your viewing, and know how to seclude anything else from focus. There were small and short extensions that appeared in the field, therefore, they were divided, not solid lines.
Lastly, I always draw the star field last on any object, except for diffuse and extended nebulae. They’re a bit more complex, and it’s very necessary to make “markers” throughout the field to make sure everything lines up correctly.
With galaxies, however, drawing the stars last is a must, especially if you choose to use ink like I do. It reduces the risk of you ever mistakenly smudging the stars. Whenever that happens, I always have to start over because there’s little to nothing you can do unless white-out’s appearance isn’t bothersome.
You may also notice diffraction spikes in my rendition.
These are mainly present in reflecting telescopes due to the secondary mirror supports, also known as the spider. The brighter the star, the more easily visible they become.
This is important because you have to draw them in proportion to the star’s brightness. Always use a ruler, never do anything free-hand, it makes things look more realistic and adds a grade of professionalism to your sketch.
Know that as time goes on you’ll get better. Never give up!
Long-term commitment to sketching these objects can improve your observing skills greatly, and you can look back on earlier observations after a few months to see how far you’ve come.
Extracted: Brandon Doyle Amateur Astronomy Online Magazine USA