A fine night out

After a long period of hazy, hot, humid, and cloudy weather we caught a break... last night's skies were predicted to be about as good as they ever get here. So I went out on an independent session to the astronomy club observing site near Spencer, Ohio -- something I have not done in far too long a time. Skies there are not as dark as they were a few years ago, but a paved parking lot, no street lights, and official permission for the activity made it acceptable.

I got a late start and had to forgo opportunities to enjoy and photograph a marvelous sunset over a broad valley. I did, however, arrive on site in time to use the fading twilight in setting up my equipment. As the last light faded the Milky Way emerged, visible from near the southern horizon to overhead and a bit beyond. Along the horizon were the summer constellations: Sagittarius and Scorpius. Saturn was sinking into the murk of the western horizon but I got a hazy glimpse of the ring world through another's telescope, already set up.

Due to not using my own telescope in some time, I suffered some difficulties in setup and alignment. I couldn't even find Polaris in the telescope mount's alignment optic and so "eyeballed" it. Surprisingly, the alignment was very good and for the rest of the night the scope was able to center or come close to all objects I asked its GoTo computer to find.

Though the sky was cloudless, it did suffer overall from light pollution or, perhaps, some lingering natural twilight. Viewing of a number of Messier objects was only fair. My old friends M81 and M82, which can be a lovely sight within the same eyepiece field of view, were barely discernible against the gray background sky. I did view, for the first time, M20 --the Trifid Nebula-- but observed no nebulosity, only the associated star cluster. The "Whirlpool Galaxy" (M51) could barely be seen at all though M31 --the Andromeda Galaxy-- put in an appearance looking, typically, like a cottonwood seed fluff.

I love refractor telescopes but frequent issue is that, when aimed straight up, the eyepiece can be uncomfortably low to the ground. So I happily got a nice view of the Ring Nebula (M57), which at that hour was high overhead, through the SCT of a companion.

In all, I viewed M11, M20, M22, M31, M51 (barely), M57, M81, M82, all in the space of a couple of hours. Then came the Moon.

As the waning gibbous Moon rose, its glow obscured the lovely path of the Milky Way and made it increasingly difficult to see any but the brightest deep sky objects. So I pointed my telescope towards Jupiter.

Jupiter emerged from behind the Sun earlier this year minus its dark southern equatorial cloud band or belt. I was eager to see. Though still low in the sky and rising at nearly the same altitude as the Moon, I was able to get a decent view of the planetary disk. Observed at several magnifications, with and without ND filter and sure enough, only one dark band was visible. I thought I could see hints of the Great Red Spot but, with the planet still low in the atmosphere, couldn't confirm that. I hope to get a better view of Jove next month but, at least, I got to see it!

I aimed the telescope at planet Uranus but that distant world was barely a dot in the eyepiece.

My project for the night was to attach my Canon EOS 50D digital SLR camera directly to my big Meade refractor -- using the 1,200mm optic as a telephoto lens. I'd never tried it before and it worked beautifully. There was some difficulty achieving sharp focus which was a surpise to me. Add to that the fact that I did not yet have a cable release for the camera and I was happy to get usable images at all. I did, however, get one very good shot out of the experiment (shown here) and will be ordering a cable release soon. That little device will help me minimize vibration -- I had to trigger the shutter by pressing the shutter release button by hand; an action that shook the entire telescope and did not help picture taking.

Packed up and left at about 11:15 a happy fellow.

Image: The Moon... both cursed and loved by amateur astronomers worldwide. It brought an early end to deep sky observing tonight but, itself, made a great subject for viewing and photographing. Canon EOS 50D: ISO 400, 1/400 sec., Meade achromatic f/8 refracting telescope: 1,219 mm. August 28, 2010, 10:54 PM. Photo by James Guilford.

Canceled August Public Night

Last night's scheduled Public Night at Stephens Memorial Observatory was canceled. Weather this year has really been an enemy to those occasions. Thunderstorms and cloud cover rolled through the area in the afternoon and evening hours. Unfortunately, at about the time I canceled the event (about 8:30 PM) some reporting stations were saying the sky was "clear." I still find that hard to believe but enough doubt crept into my mind that I felt guilt for the rest of the night. I've got to set up a team of trusted spotters I can call to check the actual sky conditions, or just go to the Observatory every scheduled night to see for myself (a bit of a drive). I hope the weather is good for September's Public Night... we'll see Jupiter (probably without its southern equatorial cloud band), Uranus, and the Moon. It'll be a great show, IF the sky is clear!

Great views of the sun with a Lunt

Today I had the opportunity to work with (okay, play with) a new Lunt solar telescope (35mm) recently purchased by the Physics Department. I was charged with the responsibility of determining what accessories might be necessary to make the scope easy to set up and use in astronomy education. The scope is nicely made and finished --a small refractor equipped with a diagonal-- complete with built-in hydrogen-alpha (Ha) filters. Easiest for the instructor is a system that allows mounting the telescope to a camera tripod; that reduces setup time to five minutes or less. The scope came with a set of mounting rings and set screws and is attached to a base frame. The base is threaded in two places to mate with a dovetail rail but those threads are standard camera threads as well. So, while not elegant, attachment to a tripod is easy and secure.

The sky was reasonably clear so I set up the telescope outdoors, added an eyepiece, and set about finding the sun. By the way, one nice thing about the Lunt is that you can use regular 1.25-inch eyepieces because all of the solar filtration is internal to the scope! The actual hard part can be getting aimed at the sun... that's one object you want to be careful when aiming toward.

Trying several eyepieces and various focal lengths I found my ideal combination with the Lunt was an ancient Kellner 12mm. The field of view includes the entire solar disk and presents an excellent combination of magnification (33X), brightness, and clarity. After focusing and tuning the filter I was rewarded with very good views of three areas of prominences in the same quarter of the sun's limb. I briefly made out a filament on the sun's surface and saw two sunspot groups, though they were not very clear -- attributable to seeing conditions. I took the scope down and stowed my gear. The next thing I did was order the simple Tele Vue Sol-Searcher --not included in the basic telescope kit-- which will be a big help in quickly and safely aiming.

I set up the telescope one more time, at about 5:45 PM, to take one more look at old Sol. Seeing had improved and, to my delight, I could now make out structure in the prominences and, with a slight tuning adjustment, filaments and some granulation. Much better than the smaller Personal Solar Telescope by Coronado. It's a fine instrument, that Lunt, and makes me want my own!

After I receive and install the Sol-Searcher I'll be returning the telescope to Physics. Before that, I hope to try a bit of digital imaging of the sun's now-active face -- but I'll need a little camera.