Monday, May 14, 2012


Sunday, May 13 dawned reasonably clear and so, with cloudy skies anticipated, a few rushed photographic observations were made of our Sun. Solar astronomers of every ilk have been excited lately by the Sun's visibly increased activity. Active Region1476 (a huge sunspot group) dominated the solar disk and astronomers' attention though it had been joined by several smaller but notable sunspots. I decided to use my beautiful new telephoto lens to try and capture images of the solar disk and my efforts were rewarded. The image wasn't perfect and I know I'll eventually get better images but it's the best solar astrophoto I've done to date! Besides the sunspots large and small, visible in this photo are granulation and other disturbances -- the chromospheric network -- in the solar atmosphere. Notes on the photography: Canon EOS 50D, ISO 400, f/8, 1/1,250 sec., 400mm Canon telephoto, AstroZap white light film solar filter, May 13, 2012 at 9:15 AM. Sky was generally clear but this shot was made through a persistent, thin cloud trail left by passing aircraft.

Friday, April 6, 2012

Shooting stars


A few nights ago I did a bit of fixed-tripod astrophotography to attempt to capture the conjunction of Venus and the Pleiades. I had to work pretty hard to salvage the conjunction photo but wasn't all that pleased with the results. Since I had a decent clock-drive sitting mostly unused, I decided to mate my camera to that and see what I could get. Not a pioneering venture, to be sure, but I've actually never piggybacked a camera to a telescope before! A quick trip to the local Ace Hardware store produced the stainless steel quarter-inch screw and a pair of rubber automotive washers I'd need to mate the telephoto lens tripod mount to the telescope's dove-tail mounting bar. Shortly after dark on this clear but full Moon-lit night, I toted the Orion SkyView Pro tripod and mount out to the sidewalk. After a rough alignment with Polaris, I attached the camera rig to the mount and did 10 exposures: about five each of Orion's Sword and the Pleiades star cluster -- both in the twilight western sky. I'll definitely need to use the DSLR's advanced feature that allows its view finder mirror to flip up before beginning exposure -- several shots were ruined by vibration. Focus was a bit more of an issue than I expected. Tracking? Well, I expected it to not be perfect but it appeared good enough for exposures of up to 15 seconds. Given all that, I'll share my results here. I know they're not very good but I also know that, using this same camera gear with better mount and alignment, I'll be getting some very nice images of the stars in the not-too-distant future!

Monday, April 2, 2012

Venus joins the Pleiades


A clear evening sky gave me the opportunity tonight to see planet Venus floating right below the beautiful naked-eye star cluster, the Pleiades (M45). The combination was beautiful through my binoculars, just before 8:30 PM EDT. I decided to make a quick try at recording the scene with my camera and 400mm telephoto lens mounted on a tripod. The problem, of course, is that an exposure of any decent length will cause the stars to form curved lines as they appear to move through the sky. Even my brief five-second exposure was no different... it looked great in the camera's built-in LCD preview panel but pretty sad on the big computer screen. So I used a bit of crude Photoshop work to round out the stars. The result won't make the pages of Astronomy or Sky & Telescope magazines but it's not too bad and saved the shot. This, and a very intriguing result from the nearby Orion Nebula (M42), makes me eager to get out on another clear night and spend some time with the camera mated to a tracking mount or piggybacked on a telescope!

The Photoshop work, by the way, was a duplicate layer used with "blending mode" set to "Darken" and then used as an offset filter. The offset filter is nudged around until the best combination of masking and brightness is found. I found the process described in a forum discussion on Cloudynights.com.

Sunday, March 25, 2012

More moons than ours in this conjunction


Tonight, and for the next couple of nights, Earth's Moon joins this spring's conjunction of Jupiter and Venus in our western evening sky. Tonight the clouds cleared just in time for the show and I stepped outdoors, tripod-mounted camera in hand, to record the sight as best I could. The three objects, on the list of brightest in the night sky, formed a very elongated triangle with Jupiter and the Moon forming the base, and brilliant Venus at the peak. The three were visible in bright twilight but really came into their own around 8:30 EDT. Later, as I processed my photos, I was surprised and delighted to see I not had captured Venus, Jupiter, and the Moon but, in a tighter shot, a couple of Jupiter's moons as well! The nighttime portion of the Moon's face is lit by Earthshine. Canon EOS 50D: ISO 800, f/4, 1/4 sec., 200mm — James Guilford, 8:34 PM EDT, March 25, 2012

Sunday, March 18, 2012

Mars mystique strikes again!

I arrived at Stephens Memorial Observatory early in order to sweep up the inevitable accumulations of bird poo and nesting materials that blow down from the dome's ill-sealed shutter. The first of the evening's surprises happened when I touched the pull rope to open the shutter to a then-clear sky. I heard scratching sounds -- usually the sign of birds roosting and nesting above. In the spring time, especially, I hate the sounds of bird activity at Stephens; birds build their nests, lay their eggs, and rear their young in a space that becomes precarious when the dome's shutter is opened. In recent years we usually see one brood (eggs, chicks, or unfledged young) lost due to falling from a destroyed nest or trapped inside the dome. This time, however, I glanced above and was momentarily shocked for I saw a black, furry animal scrambling to escape and prevent a fall. Skunk!? Er, no. The frightened furry was one of Hiram's many black squirrels. I've never seen a squirrel in the dorm or in the shutter and hope they don't nest there but maybe they'll keep the birds from nesting. I'm hoping for the best, anyway.

Cleaning barely complete, the telescope uncovered and prepped for the first Open Night of the year, I decided to try my chances at seeing Venus. The planet has recently been in conjunction with Jupiter in the Western evening sky and, though below the neighboring treeline, the trees were bare and I could spy brilliant Venus between the branches! Yes! For the first time at Stephens I was able to see Venus, resolved as a half-lit disk! Then the evening's first visitors arrived... three young ladies and their grandmother, half an hour early. I offered them a look at Venus but, by then, the planet had slipped behind a tree trunk and could not be seen. Oh well, let's see if we can view the Orion Nebula, barely above the trees in the southwest and now visible in the darkening sky.

I swung the big refractor around, found the nebula, and focused. Not bad for a twilight view: the veil of the nebula was visible and several stars of the Trapezium were nestled within. I offered the girls a look at M42. Er, no. In that brief time between adjusting the telescope and fetching a ladder for the kids, clouds covered Orion. Eeek! All right then, we'll go to the other part of the sky and look for Mars, now glowing red in the east and not long after opposition.

Mars, 67 million miles away this night, quickly came into view as a crisply-defined coppery disk. Unfortunately there was only a hint of mottling within the disk, no clear indication of surface features. Grandma and the girls got decent looks at the Red Planet before, yes, those pesky clouds engulfed it! By then other visitors began to arrive. The sky became overcast with occasional "sucker holes" and thin spots. Well, this will be a short night, I thought.

I answered questions, recounted the history of the telescope, talked about the Observatory, all the while watching the sky and keeping at the telescope. When Mars would penetrate the gloom, I'd  re-aim the scope, call people over to look, they would see an even less-distinct reddish disk, and it would disappear. Apologies. And so it went for the entire evening. There was no sense in trying to chase the holes and point at some star or other that managed to be briefly seen through the overcast. Still, more visitors dropped in.

Over the course of the evening we counted 42 visitors, most or all of whom caught a glimpse of Mars. They were, to a person, patient and good-humored making it a pleasant night that ended with the last departing around 10:30.

Not long after that, as I was deciding whether to close early, the clouds parted overhead exposing a deep, dark sky! The night was filled with stars and with my unaided eyes I was able to make out the Beehive star cluster (M44) nearly overhead. It was beautiful through binoculars. No more visitors, however, so I closed the place up.

Everyone could see it was an overcast sky as they headed out to visit us. They could see a star or two, only occasionally at best, and still they came. Such is the draw held by the mystique of Mars!

We'll try again April 14.

Sunday, February 12, 2012

Ptolomaic vs. Tychonic

Competing Concepts of the Solar System - Philosophia Britannica - Benjamin Martin

Last Christmas my brother presented me with a thoughtful and interesting gift. Carefully rolled within a golden cardboard tube was a page from an unbound book. The sheet, yellowed with apparent age, was nonetheless in good shape. On the illustrated face were two sets of concentric, multiple circles -- depictions of competing concepts of the organization of our solar system. Turns out the page was an original, bought by my brother from a company that specializes in such things! Here's what was printed on an insert that accompanied the sheet:

"This is an original engraving from the 1771 edition of the Philosophia Britannica by the British author, mathematician and master instrument builder Benjamin Martin (1704 - 1782) contrasting diagrams of the planetary system according to Ptolemy and Tycho Brahe - note anthropomorphic sun at the centre of the latter.

"At his well equipped Fleet Street shop Martin made beautifully crafted telescopes, octants, and microscopes, as well as elaborate orreries and planetaria. Trained as an engraver, it is believed that Martin himself engraved some of the plates that illustrated the work."

For all of its age the sheet is in remarkably good condition. The worst of it is creases, the result of folding. I'm pressing the page now, in hopes that some of the curl and crease will subside. Still in all, a notable piece and a lovely gift. Thanks, Will!

Saturday, November 12, 2011

Thin clouds but a good night


Open night at Stephens Memorial Observatory: Thin clouds didn't keep 27 people from visiting this night and enjoying fine views of the giant planet Jupiter and its Galilean moons. We observed Jove's twin equatorial cloud belts, some additional bands of clouds, and a few sharp-eyed viewers caught glimpses of the Great Red Spot (actually, my first!). Adding to the experience, one of the four visible moons moved closer to the disk of the planet as the night progressed. Eventually moon Io began its transit across Jupiter, first visible against the south equatorial band, then disappearing into the planet's glare. Earth's Moon put in an appearance far later than I'd have wanted -- I got the timing wrong back at the beginning of the year whilst setting up our schedule! Most visitors viewed it as it rose through clouds and neighboring trees, then they headed home. They did, however, spy lunar seas and craters through a network of bare tree branches resembling eyelashes, said one viewer. Our last visitors of the night, however, were rewarded with our usual clear, bright, and astonishingly beautiful lunar sights as presented by the great Cooley Telescope. One, an experienced sky watcher, said it was the finest view he'd had of Earth's neighbor in 40 years of observing! As we left the observatory at the end of the event we looked up at our Moon floating in a thin sea of cloud and there, surrounding it at a good distance, was a beautiful halo... a fine way to end the evening!

Photo: The Moon as viewed through the Cooley Telescope of Stephens Memorial Observatory, Hiram College, Hiram, Ohio, November 12, 2011. Afocal technique with Canon PowerShot G11: ISO 400, f/4, 1/500 sec., at 8:57 PM. Photo by James Guilford.