Wednesday, September 2, 2009

Private observing

The forecasters all indicated last night (Sept. 1) would have very good seeing conditions and, because I wasn't due in to work until Monday afternoon, I decided to go to the Observatory and enjoy a little private observing. The session would also give me a chance to check on the facility and experiment with the telescope's faulty right ascension clutch.

Except for the dehumidifier bulk tank being nearly full, the place was fine. That was a relief since not long ago a severe thunderstorm with possible tornado passed a few miles to the south of Hiram.

It was my belief the hand control for the RA clutch was not able to turn far enough to lock the clutch and engage the telescope's clock drive. I removed the control linkage and manually tightened the clutch. Sure enough, the telescope began tracking decently (considering all of the mechanicals are a century old). I'll see if I can rig a kluge remote of some sort until a permanent fix can be arranged.

Seeing conditions were very good for the Moon, at least. The waxing gibbous Moon dominated the sky wiping out all but a trace of the Milky Way and dimmer stars. There were also traces of high, thin clouds later in the night. I experimented with afocal photography using a new digital SLR camera and got mixed results (see image above). An apparatus holding the camera in alignment with the telescope eyepiece would help a lot. I also got a halfway decent image of Jupiter's planetary disk with the handheld camera! Seeing wasn't as good as forecasters indicated but I was surprised at how well it photographed using this simple, unsteady technique. The Galilean Moons showed only as the faintest specs in the photographs though they were brilliant in the eyepiece.

I experimented with --and failed-- using the telescope's RA dial and clock to guide me to M31 - the Andromeda Galaxy. I need to devote a good dark night to that and learn it well. Too bad our declination rings are messed up --still more work to do-- for their use would help.

Using binoculars I was able to spot M31 and, in stages, nudge the big telescope into proper aim. The big galaxy looked very nice (to me it looks like a cottonwood tree's seed) though a darker background sky would have helped contrast and aid in seeing its soft outer edges.

Finishing off the night I tried some moonlit photos of the Observatory and the grounds. Mixed results there but it was fun trying.

Next public night is Sept. 12 and Jupiter is the featured object.

Sunday, August 16, 2009

Hot Jupiter!

Saturday, August 15 was a Public Night at Stephens Memorial Observatory. It was hot, hazy, and humid and, though viewing was set to begin at 9:30, folks began arriving just a little past 9:00 -- a sign it will be a busy night!

As twilight began to fade I trained the telescope on the red giant star Antares. The idea was to nudge the telescope a bit as the sky darkened and look at the neighboring star cluster M4. That didn't happen as constellation Scorpius was sinking into the trees to our south and west taking the star cluster with it.

I made an attempt to locate the beautiful star cluster M15 but could not find it. As Jupiter was rising from behind trees to our east, moved on to that planet. Lower-level air was hazy but the atmosphere was quiet and seeing steady. We were treated to some excellent views of Jupiter at low power (about 30X) and, much later, at 104X. The equatorial cloud belts were visible nearly all of the time and we occasionally saw traces of the north and south temperate cloud belts. Truly impressive.

The excellent turnout --more than 50 visitors including at least three children-- made it difficult to change magnifications and celestial objects during the course of the evening. Those who stayed late and were patient saw the higher magnification views of Jupiter plus a good look at the "faint-fuzzy" M31 -- the Andromeda Galaxy (actually looking quite bright with central brightness and extended nebulous area). A couple of satellite passes and at least one meteor (likely a late Perseid) were seen through the dome slit.

Light pollution illuminated the hazy lower atmosphere making low-elevation skies murky and bright. Stepping outside and looking directly overhead, however, we could easily see the great band of the Milky Way stretching across the sky, replete with dust lanes. The star cloud did not quite reach down far enough to the south to join constellation Sagittarius before being swallowed up in the bright Earthbound haze.

Last visitors to leave were a couple who were curious about constellations and what star cluster it was they saw the other night -- the Pleiades. We spoke for several minutes sharing meteorite experiences in the front lawn. I closed up the Observatory at about 11:30. It was a hot night but the seeing was excellent.

The telescope's R.A. tracking is pretty bad. Troubleshooting shows the clock is working well and the gear train is transmitting motion so the conclusion is the R.A. collar is slipping. I hope to address that problem within the next month.

Thursday, August 13, 2009

Perseids Meteor Watch

The 2009 Perseids Meteor Watch I worked last night (August 12) was very mixed in results. The Portage Park District set us up in a fine little park with no ground-level lights, a nice paved parking lot, and clear grassy areas. There was a wide view of the sky and a good southern horizon. A Sheriff's deputy was on hand as was the District's naturalist -- really good support, especially in case of a big turnout. Then there are the "buts"...

Admittedly we put the event together in hurried fashion. Word didn't get out to the public as broadly or with enough lead time so only a couple of families showed up.

Then there was the sky. We were very close to the city of Ravenna but I'd hoped we would be just far enough away to escape the light bubble. Not much luck there. As the Sun sank below the western horizon a funny thing happened ... twilight shifted to the south. Yeah, huge levels of light pollution rose up in the southern sky right through the heart of Sagittarius. So while the clear skies allowed us to see the Milky Way, with dust lane, directly overhead, its heart was obliterated by the "Ravenna Nebula." Too bad.

Attendees and volunteers did, however, enjoy a few very good Perseid meteors. I myself saw only about five; being busy with telescopes and chatting with visitors has its costs. The 6-inch Meade telescope worked well but was impeded for want of a really good polar alignment: it had problems centering on objects it was told to "GoTo" but tracked very well once there. The dew point was high and everything quickly became quite damp, even wet, as the night progressed. The extended AstroZap dew shield saved the objective from fogging, however, so we saw decent views of Jupiter with three moons, and very good views of the Andromeda Galaxy, and M15 (a globular star cluster in the constellation Pegasus).

I tore down after the official 11:30 close. Before getting into my car to leave, a very nice Perseid streaked across the sky leaving a trail that glowed for a second or two -- as if just for me. I headed home, a bit disappointed but recalled a few happy visitors who saw planets, stars, galaxies, and meteors!

Sunday, July 12, 2009

Public Night July 11

This was the first Public Night at Stephens Memorial Observatory since the dome shutter mechanism was repaired. Weather during the day made the night's activities doubtful. The region had suffered strong thunderstorms with plenty of lightning, rain, and wind. As predicted, however, the storms departed the area as quickly as they came and left us with a sultry evening and clear/clearing skies. The first of our 25 visitors for the night arrived early and helped dump the office dehumidifier tank --probably about 20 gallons-- and more visitors gathered as night fell. Daylight Saving Time has pushed twilight well beyond our 9:30 start time so we stalled until about 10:00 when stars began to become visible followed by our true target for the evening: globular star cluster M4 in the constellation Scorpius. As the skies darkened we could begin to see tiny, diamond dust-like stars resolving in the center of the cluster's diffuse cloud-like appearance. Despite that, star clusters aren't a sight that "wows" the public but our visitors paid polite attention and expressed interest in what they were seeing. We also viewed stars Antares and Altair, the latter impressing even yours-truly with its colorful brilliance. At 10:45 a thick bank of clouds moved in to cover the sky and put a stop to our improved seeing. A modest success, this night, but I can hardly wait to show people Jupiter and the Moon in a month or two; they're real crowd-pleasers!

Sunday, June 21, 2009

Astronomy class semi-success

The weather forecast was all over the place for tonight's Hiram College astronomy class visit to the Observatory. Would it be cloudy, rainy, partly-cloudy, clear, clear but poor seeing? We saw all of those forecasts. It looked like it might clear up for the 9:30 start so we called it a "go" and opened up. About 18 students with their professor attended. Started off with the usual historical and interpretive talk about the Observatory and telescope while we waited for the sky to darken. We had partly-cloudy skies and sultry 80-degree air for the start, first viewing the red super-giant star Antares. Sometimes it winked out of sight as a cloud passed, then it would reappear. When everyone had seen the colorful blip, I moved the telescope to the neighboring star cluster M4. Seeing was not good but I could make out a faint cloud of stars and a few students also said they saw it. Many could not observe it. So the Clear Sky Chart prediction of poor seeing was pretty much confirmed. Clouds closed in at about 10:30 so all went home. The professor asked if we could schedule a lunar observation night during the last week of June or first part of July just before the end of the course. Hopefully we'll have a better night because the old telescope really shows its stuff with the Moon when viewed through its fist-size, low-power eyepiece. Driving home I encountered partly-cloudy skies, moderately-heavy rain, and clear skies! I'm happy not to be a meteorologist trying to forecast this!

Monday, May 25, 2009

Dome trouble


Well, we had trouble, my friend! During our April 4, 2009 public night, the shutter began acting up. It was difficult to open for the night and was nearly impossible to close (see previous post)! College carpenters built up a scaffold inside the dome early in May and determined that the rollers that carry the shutter had derailed -- nominally the rollers move along an iron bar at the top of the opening easing operation. The craftsmen lifted the shutter back on to its tracks and lubricated the wheels. With the scaffold in place the telescope could not be moved so all use of the Observatory was suspended during the balance of April and through May. While the scaffolding was still in place, over the late-May Memorial Day weekend, I replaced the pull ropes that are used to manually open and close the shutter. I have no idea how old the cotton rope was; I replaced it with a tough poly braded rope. The shutter works better than it has in years though close examination of the condition of its wooden components left us with worries.

May offered a number of clear nights which was a big change from an otherwise very cloudy spring season. Unfortunately needing to be fresh for work and a nasty late-May head cold kept me from taking advantage of the clear night skies. Hopefully this will be a good year for me and I have hopes of using both the Observatory and my private telescope(s) more frequently than in recent years.

Photo: Crammed inside the Observatory dome is a large scaffold used by workers to repair the troublesome dome shutter. The hundred-year-old sliding wooden cover had become derailed. Taking advantage of the presence of the sturdy apparatus, I replaced operating ropes and inspected the upper reaches of the dome and shutter ... it wasn't pretty!

Sunday, April 5, 2009

Tough night at the Observatory

Saturday night, April 4, was to be the first scheduled Public Night at the Observatory of the year not canceled by weather conditions. As forecast, the skies cleared and promised to cooperate for the night's event giving us fair seeing and temperatures in the mid-30s. Because of previous cancellations the Open Night was to serve as our official Saturn Observation Campaign event for the spring and we registered as a local site for the global "100 Hours of Astronomy" which is a part of the International Year of Astronomy observance.

Despite clear skies our events nearly did not happen. Pulling the ropes to open the observatory's dome shutter I head a loud squawk echo through the chamber -- the shutter had jammed for some reason and would not open fully and would not close. Repeated efforts finally resulted in the shutter opening all the way and we were free to see the sky.

The night saw 26 visitors between 9:00 and 11:00 and they were treated to superb views of the Earth's Moon. As usual the old nine-inch scope excelled at lunar landscapes but the Moon was very high in the sky --not far from the zenith-- and the telescope was not tracking well. We settled for moderate magnification (133X) and enjoyed nearly three-dimensional viewing of Mare Imbrium's crater-marked lava expanses. Wrinkled crater walls, mountain ranges, and long, low, lines of hills looking like frozen ripples in hardened plaster were seen vividly. Views of Saturn were also quite good: the rings tipped towards us at only about three degrees (minimum tilt was reached in January but we missed that). Moments of very good seeing revealed a slight shadow across the planetary disk cast by the rings and a hint of gap between the planet's limb and the inner rings. A special treat was the sight of four of Saturn's moons and, over the course of the evening, noting their changing positions relative to each other and to their planet. Galileo, 400 years ago, never saw the Moon or Saturn a fraction so well as we did. He was, however, very meticulous and a skilled observer of what he could see. The Moon, while beautiful to look at, also lit our less-than-perfectly transparent skies causing quite a bit of glow so we confined ourselves to viewing only it and Saturn. The last visitors departed at about 11:10 PM.

All was routine as I began closing up until I attempted to close the dome. Squawk, boom! The shutter stalled and jammed again on its tracks. This time, however, it was stuck. After many attempts with the ropes I climbed into the opening. I found one of the lower wheels on the shutter had derailed so I lifted the shutter back on to the track. Not enough! The main problem was with the track at the top of the dome! There's no way to reach that point without scaffolds or ladders. It was going on midnight and I didn't know what to do but to keep trying. If anyone was watching from outside it must have been quite a sight... the silhouette of a man in the aperture, bright lights on inside an observatory dome, pushing and pulling and shaking the shutter, until finally it settled into its closed position. Tired, sore, and worried, I shut off the lights, locked up, and headed home at about 12:30 EDT. What a night!