Dew Test and Dark Nebulae

Happy Autumn!

Drifter observing report,  9/21/2019, Eagle’s Ridge (912m), SQM 21.2: Saturday was the first dewy night for the beta Drifter. Since I don’t have active dew heaters installed yet, this was a good chance to try out an idea that’s been kicking around in my head: Shove some chemical hand warmers into the cavity in the secondary mirror mounts and see if that can provide some dew relief. Of all the Drifter’s optical surfaces, the secondaries are definitely the greatest dew risk. The hand warmers were too large to fit inside and close the lid over, so a lot of the heat generated was radiated out into the night sky. One secondary stayed dew-free, one did not, so I’m guessing there was some inconsistency in my folding and chemical activation methods. But the idea shows promise! For regions like ours where dew is only occasionally an issue, this method is dramatically simpler than embedded dew heaters wired to a dew controller and a battery pack. I’m especially interested in this being a low-cost, low-weight solution for the Swift.

However, an active dew heating solution is one of the first things that will be tested on the Drifter through the crowdfunding campaign. The secondary mounts and tertiary mounts are already designed to take Kendrick stalk-style dew heating units. The primaries are both cooled and heated with boundary layer fans. Wiring channels are already printed into each part and the scope is designed to use an internal 7ah LiFePO4 battery pack as a counterweight. Many binocular telescope designs have ignored dew management, but it is twice the problem on binoculars. Believe me, it’s frustrating! After one particularly dewy night with the alpha prototype, I packed it in before first light on the Great Orion Nebula! On the Drifter, dew management will not be an afterthought.

On to the objects! The thing that stood out for me the most was my first observation of NGC 6572, the Blue Racquetball/Emerald/Turquoise Orb/Emerald Eye/Planet Krypton(!) Nebula. At 57x in the Morpheus 17.5mm eyepieces, it floated there in a field of 100 or more stars, radiantly teal. Just as it can shift in and out of color through one eye depending on whether you’re using rods or cones, the effect through two eyes is even more dramatic. The depth of color was really astounding though, even at low magnification.

The small group of three fellow observers had already seen the Lagoon Nebula through the Drifter, but they still took a perhaps-final peek as it descends into the horizon. The view that impressed everyone the most was the widefield view around M11, the Wild Duck Cluster. At 2.2 degrees, the cluster was almost completely surrounded by dark nebulae. The Barnard 114-118 complex stood out vividly compared to a one-eyed view through either the 10 or 12” scopes present. The view invited observers to drift around exploring two dozen dark nebulae, and of course the clusters sprinkled around that region of the sky. Binocular vision brings dramatic contrast to the Milky Way. These objects are transformed from “Oh yeah, I kinda see that” to “Wow, this is so amazing!” They’re vivid, they have nuanced shapes, and they’re just delightful to behold.

This was also the first time the beta Drifter pointed at M33, Triangulum Galaxy. A clear spiral pattern could be observed in the arms. Of course, because the Drifter is correct left-to-right, M33 spirals clockwise in this scope. NGC 604 stood out, but I regretted not knowing my M33 geography better. There are many interesting features to this galaxy and I look forward to returning for further study. Even at 57x, it felt big.

Crowdfunding progress: More design happened this week on the Swift kit scope. The more I work on this scope, the more excited I am about it. The vertical height of the collapsed scope will be cutting it close, but I still think it can be airline carry-on compatible by removing the feet. Stay tuned! My hope is to show you a first complete sketch of the whole scope in the next email.

The mailing list is very close to 500 subscribers! If you know anybody who might want to observe dark nebulae in a whole new way, please let them know they can subscribe at: https://analogsky.co/#email-signup 

Thanks for reading, hope your skies stay clear for a while longer! Here in Western Oregon, we are already back to prime telescope building weather.

Leave a Comment