This blog is inaccurately namedOctober 28, 2014
Way back in September 2007, even before I had obtained my first telescope, I started keeping a log of my astronomical observations. A bit over seven years later, that log is an Excel spreadsheet that runs to 2564 lines, documenting 595.5 hours of telescopic and binocular observations spread out over 429 observing sessions. As far as I know, I have not missed a single session.
One thing you can tell right away is that my average observing session is a heck of a lot longer than 10 minutes. On average, over the last seven years I have gone out observing 61 times per year–about once every six days–and stayed out for an hour and 23 minutes per session. But this is horribly misleading. In truth my observing sessions split pretty neatly into two bins: those sessions that last 30 minutes or less, almost always conducted from my yard or driveway, and those sessions that last hours and hours, from Mt Baldy, the Salton Sea, Owl Canyon, the All-Arizona Star Party, and sundry other places that I’ve gone someplace else and set up a scope for an extended period. As time has gone on, those extended sessions away from home have occupied a progressively larger proportion of my observing in any given year. Here are some relevant numbers:
- 2007 (last three months): 45 sessions, 25.81 hours, average of 34 minutes per session
- 2008: 85 sessions, 67.48 hours, average of 48 minutes per session
- 2009: 110 sessions, 101.66 hours, average of 55 minutes per session
- 2010: 95 sessions, 166.73 hours, average of 105 minutes per session
- 2011: 18 sessions, 47.23 hours, average of 157 minutes per session
- 2012: 57 sessions, 101.34 hours, average of 107 minutes per session
- 2013: 26 sessions, 59.62 hours, average of 137 minutes per session
- 2014 (so far): 9 sessions, 25.67 hours, average of 166 minutes per session
Another thing the numbers at this level do not reveal is just how clumpy my observations are. My biggest sustained run of regular observing was July 2009 to November 2010, when I observed 161 times in 17 months. That was followed immediately by a long dry spell, December 2010 to January 2012, when I only observed 19 times in 14 months, and in half of those months I made no observations at all. From May to September 2013, I only went out twice. This year I did not observe at all between January and June. My islands of productive observing are separated by increasingly large gulfs of not-observing.
What gets me out often? Observing programs. I did almost all of the observations for the Binocular Messier and Deep Sky Binocular clubs from my driveway, in short sessions. Ditto for the Double Star and Urban clubs. Although I made up logbooks for the Bino Double Star Club and for O’Meara’s Hidden Treasures and Secret Deep, I haven’t started those observations yet.
This has implications for my decisions about gear. It doesn’t make sense to keep a large stable of telescopes when I might only get out 20 times in a given year. And if I’m going to a distant site for an all-nighter, I don’t want to take a whole bunch of scopes, I want to take one, or perhaps two at most.
If money was no object, my ultimate gear list would be pretty short: a big Dob for chasing faint fuzzies, a compact mid-sized telescope that could do almost everything, a smaller or more break-down-able scope for airline travel, and some image-stabilized binoculars for bino observing. I always figured the Dob would be a 14″ or 16″ ultralight truss or strut design, but as time goes on I increasingly wonder if I’ll ever pony up the money for such a scope when the XT10 has so much to show me. In the CN thread “Where does serious aperture begin?”, Don Pensack wrote:
For years I thought an 8″ scope was a “lifetime” scope. Probably around 15000 DSOs are reachable, and pretty much all star clusters. You could spend a lifetime with one and become quite an accomplished observer.
Given that my tally of total objects observed probably stands at around 500 (110 Messiers, 170 other NGCs, ~75 southern-sky objects, 100+ double and multiple stars, 20 or so planets, moons, and comets, sundry IC, Collinder, and Stock objects, asterisms, etc.), it seems kinda silly to dream about a scope that would show me more than the ~20,000 objects left to see in the XT10, especially when said scope will (a) cost a lot more, and (b) be more of a pain in the rear to set up (since the XT10 is no hassle at all).
For a while I thought my compact, do-everything scope might be the Apex 127. But that was before I got into widefield observing and drank the refractor Kool-Aid. Now I think only a 4″ or 5″ apo will do, but that will set me back as much as the 14″ Dob. In other words, not something I’ll be purchasing anytime soon. Ditto for the image-stabilized binoculars. They’re nice, but they’re not urgent.
And, in truth, none of this is urgent. My current scope lineup lets me do about anything I want to, and I’ve always been fascinated by pushing humble equipment to its limits. Although I did get one new scope recently–more on that in the next post.