NGC 2841

First light for the Celestron C9.25 XLT! I recently acquired this scope for the purposes of going after more distant objects (like galaxies*) and objects with smaller apparent size (like planets). This is the first SCT I’ve owned. In principle, it was appealing to me that the SCT could image at F2.2 at 525mm focal length with the Starizona Hyperstar; F4 at 940mm focal length with Starizona Night Owl Reducer (similar FL and speed to my Newtonian); approximately F6.3 at about 1500mm with the Starizona SCT Corrector IV; F10 at 2350mm at native focal length; and F25 at 5,875mm with a 2.5x Powermate for planetary (we generally have pretty good seeing here at 6300’). I should be able to capture nebulae and galaxies both large and small, our own solar system’s planets, exoplanet transits, and perhaps I could even do some star analysis - all in one package. I’m hopeful that this scope really is as versatile as it seems to be on paper, and I look forward to working with it more. I found that getting reasonably good collimation on the scope was easier to achieve with the SCT than my Newtonian. I’m hopeful I need to collimate it less often than I did it on my Newtonian (which wasn’t terribly frequently to begin with, but I still had a tough time getting it dialed in for months - user error.) Having read about issues such as mirror flop and image shift when focusing with non-Edge SCTs, I opted to add the Baader Diamond Steeltrack SCT Focuser (with EAF mounted) for more precise focus throughout the night, and to reduce or eliminate concerns about image shift.

For my first light with this scope, I went after a new target: NGC 2841. This galaxy starts around 60 degrees, peaks pretty close to the Zenith at about 74 degrees, and then I switched to another target when it hit about 45 degrees in my session, so I thought it might be a good test for any image shift or mirror flop. I shot for 7 hours, and tossed a few frames due to what appeared to be some bad guiding (perhaps due to some wind… or maybe the bunny I’ve seen in my yard lately hopped by and bumped the power cables a few times, idk). Either way, it performed well all night. I’m still working on dialing in guiding as best I can, as it was hovering around .65” RMS all night, which I’d like to get down a little lower to .55” if possible since my pixel scale is about .52”, and the seeing here generally seems to support imaging at this pixel scale (according to MeteoBlue it is typically around .8-.9”… last night it dipped down to .5”) I’m also pushing the limits of the EQ6-R Pro with this rig, so that may be about as good as guiding it gets for me!

In processing this image, I did notice a bit more noise when I tried to push the saturation like I typically would with my Redcat or the OOUK Newtonian. Both are a bit faster focal ratios, and I typically image less distant objects, so I think I’ll probably need to add a few more hours of integration time to each target to achieve similar color saturation results without as much noise. After all of that work getting it set up, I’m happy with how this first image turned out!

*NB: I’ve always been fascinated with galaxies primarily because of their scale and extreme distance form earth and their massive populations of stars. I feel fortunate to be able to contemplate these things. For me, galaxies really hammer home the vastness of our universe… Our tiny blue dot is one of several planets that revolves around our star, which is just one star out of of hundreds of billions of stars in our own galaxy, which itself is just one galaxy out of hundreds of billions of galaxies in the known universe. It’s humbling.

The most common philosophical questions that seem to have persisted throughout most all civilizations in human history are some form of “what are the origins of life?” and “are we alone in the universe?” Many have opined on these questions throughout history, with some suggesting that conditions on Earth are “just so”; that everything came together over time in just the right way for earth to support the emergence of life. However, I have found the most compelling thoughts around these questions come from the world of complexity science. Complexity science was born as a cross-disciplinary study of systems and how they interact and show emergent behavior over time and across different scales. Astronomers, physicists, economists, biologists, computer scientists, and practitioners from so many other disciplines have benefitted from the insights of complexity science. In his book At Home in the Universe, Stuart Kauffman of the Santa Fe Institute finds the “just so” theory to be lacking. Essentially, he suggests that life is actually an inevitability given the laws of physics and chemistry (such as the second law of thermodynamics and entropy) and the broader principles of complex systems (such as scaling, emergence, and spontaneous order). Given that we can trace life on earth to these physical and chemical processes and the laws they follow, surely other places in the universe that follow the very same laws have equal chances at harboring life?

In my view, with this context and given the scale of the universe, determining if we’re alone in the universe becomes a numbers game. People who are smarter than I am think there are 200 billion to 2 trillion galaxies in the known universe, and that on average, there are about 100 billion stars in each galaxy, and approximately the same number of planets as there are stars in every galaxy. So let’s assume there are 500 billion galaxies in the known universe, each like our Milky Way with at least 100 billion stars in its orbit and one planet around every star. That would mean there are 50 quintillion planets in the known universe. Let’s also assume life’s emergence on Earth within the Milky Way is representative of the broader universe. That would mean there is a .000000001% chance of life emerging on a planet - that’s 1 hundredbillionth of a percent of a chance. Multiplying our estimated number of planets by our fractionally tiny chance of life emerging on a planet (using the unlikely but demonstrably true assumption that we’re the only planet in the Milky Way to harbor life), you still end up with some 500 million planets in the known universe harboring life! Surely the answer to the question of “are we alone in the universe?” must be “No!”