June 7, 2025

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It's been a while, but my lack of new posts has a good cause: I finished my next book, and it's just about ready to debut later this year (October 28th, to be precise). The book tells - as my publisher says - "the untold story of how environmental change throughout the cosmos shaped human history." I hope it's a good read! It certainly took me long enough to write. And one interesting aspect of the book is that it draws not only on my research as an academic, but also on my experiences as an amateur astronomer - experiences I've chronicled in this blog. 

Another reason for my silence is that the weather has been pretty bad here in Washington, DC. Either it's been cloudy, or the atmosphere has been turbulent, or (lately) it's been smoky, owing to the fires in Canada. Now, on November 8th of last year, I did manage to step outside with my TSA 120 on a glorious night for astronomy. I wanted to write about that - until I was swamped with last-minute editing work. 

This is an idea setup: The TSA 120, a NoH's Mount CT-20, and a Berlebach Uni tripod. Lightweight and rock solid.

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Had I had time to publish here in November, I might have had more to write. But I do still remember the look of the Galilean Moons that night. The seeing was so stable - and the TSA 120 is so good - that the moons resembled not points of light, but hard little discs, each with a different color. At a magnification of about 150x, I experienced the illusion that if I magnified just a bit more, I'd be able to see surface detail on a couple of those little moons. Unfortunately - as is typically the case here in DC - cranking the magnification beyond 200x did not produce a better view. 

A few months ago, I also experimented with a new "smart" telescope: the Dwarf 3. I intend to write about that at greater length in a forthcoming post, when I'll compare the Dwarf to the Vespera and EVScope. I'll say for now that I was nearly run over by a train in rural Pennsylvania while imaging M81 (Bode's Galaxy). 

The Moon with the TSA 120 and an iPhone 15.

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In any case, a couple nights ago the wildfire smoke mostly drifted away, the atmosphere was mostly stable, and I stepped out with my TSA 120 to do one of the things I love most in life: exploring the infinitely complex landscapes of the Moon when our neighboring world is halfway illuminated. I set up my telescope in the courtyard of my building, and as I started peering through the eyepiece I could just hear a neighbor beginning to play soothing - and actually, slightly eerie - melodies on his acoustic guitar. It made for a perfect soundtrack as I worked my way from the enormous gash of Vallis Alpes in the Moon's northern hemisphere (it always looks to me like someone grazed the Moon with a giant knife) to the tidier and more diminutive straight line of Rupes Recta in the south. 

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As usual, I took pictures by holding my iPhone up to my Delos eyepieces. I've become pretty good at holding my phone with a steady hand, but amateur astronomers know that, in any snapshot of the lunar surface, the inescapable undulation of the atmosphere tends to blur the fine details that are visible with the naked eye. So it is in the pictures, above. They may look pretty impressive - especially when you consider that I took them with an iPhone - but the view was actually that much better. Limitless detail, and endless complexity. 

One of my weaknesses is that I like to compare and rank things - it must be genetic, because my eight-year-old daughter has developed the same trait. It also seems to be a common affliction of amateur astronomers. Naturally, after having had a particular good observing session with the TSA 120, I began to consider how the telescope measures up to others I've tried - when it comes to lunar viewing, at least. 

In short: I think it measures up to anything I've used, and that includes the Mewlon 210, the TEC 140, and the APM 140. Actually, that might not be going far enough. On the Moon, aperture matters, of course; so does the overall optical quality. But two characteristics that really stand out are a lack of false color (a common affliction along the lunar limb in all but the finest apochromatic refractors) and crisp detail to the edge of the eyepiece (not usually a strong point of a catadioptric or Dall-Kirkham design).

This is where the TSA 120 excels. Any false color or softness in my pictures is an artifact of my iPhone camera. In reality, the view is totally color-free and sharp to the edge of the eyepiece. This is why I'd have to conclude that the TSA 120 might just be the best lunar telescope I've used. It's amazing to have so much capability in such a relatively light and compact package. 

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