Hodgson Observatory

Viewing from Sioux Falls SD. Tonight 7/13-14/ 2008 the Moon was just past half and the city lights were on as usual. The sky was fairly steady and the temperature was 66 degrees and humidity was 55%. Limiting magnitude was at 3.5.
So what can one do under these conditions with a 150mm by 750mm reflector? First I checked collimation. Just a little tweak and it was in. I set up about an hour before sunset to let the scope cool down. I set up where the street lights were blocked by trees on the south west side of my house in the drive way. The scope I am using is an Orion 6″ F5 reflector on an Apogee EQ5 GEM with an Orion dual axis controller.

At 10pm CST I went out and polar aligned. The Moon was between a neighbors house and a tree so it was the first stop. From my Magnification cheat sheet I determined to use the 12mm Orion epic ED as it would yield 63X with a 0.88 degree FOV. This would perfectly frame the 0.5 degree Moon.

The view was crisp and BRIGHT. The detail along the terminator was spectacular. Ok I am blind in my right eye now. Twilight still lingered so I will take a break for a half hour.

Back out now and my eye has recovered. It is dark now but the skies have a light gray color from the light pollution. Under these condition I like to observe around zenith but there was Saturn and Mars shining brightly in the West. They were about 25 degrees above the horizon. Turned on the Telrad and aimed at Saturn. I am using a 22mm Orion Epic ED as my finder eyepiece. Saturn was very small in the 22mm EP at 34X with a 1.6 degree FOV. The rings defiantly stood out. Pump up the power! I put in the 12mm Orion Epic ED with the Orion 2X shorty Barlow. This gave me 125X and about a 0.44 degree FOV. Much better view. There was some scintillation. Detail would come and go. The shadow of the ring on the planet could be seen and the shadow of the planet on the rings could be seen. No Cassini division though and I did not expect it due to the rings closing up and the power I was using.

OK can a nebula be seen under these conditions? M 57 the Ring was approaching zenith. I put in the 22mm ED and went to the Telrad and aimed. Then to the EP. There it was small and dim! Lets bump up the power and try some filters. I put in the 12mm with an Orion light pollution filter. It helped some making the Ring more discernible, but the back ground sky was still fairly bright. Now I tried the 12mm with an Orion UHC filter. WOW! What a view, nice dark background with the Ring standing out nicely showing a slight blue color!. Alright one more try with the 12mm and an Orion OIII filter. Very dark background and the Ring lost it’s color and also became dimmer. I feel that OIII filters are to dark (Block to much light) for this size aperture. The UHC filter worked best with the 6″. An OIII may work fine in an 8″.

Lets try it again on another nebula. M27 the Dumbell. I put the 22mm back in unfiltered. Aimed the Telrad and I couldn’t believe it, there was M57! I am an experienced observer an can star hop pretty good. M57 is fairly large so I stayed with the 22mm ED. Once again I used the assortment of filters that I used on M27. The results were the same The UHC came out on top. It showed both lobes and had a nice dark background giving good contrast.

As I said earlier, I like to work zenith under bright sky conditions. M13 was straight up. A little neck craning at the Telrad an M13 was in the field of the 22mmED. Just a small fuzzy spot. Could I get any detail? I stepped up the power with the 12mm. Just a slightly bigger fuzzy. Ok lets kick it up so I put in a 7.5mm ED. Big fuzzy with a little detail of stars coming and going in the central core. Not to bad for a 6″ under these sky conditions.

Jupiter had just come into view now from behind the neighbors house. Aim and with the 22mm ED, Jupiter, although small revealed two bands and 4 Moons. I bumped the power up with a 9.5 ED and was rewarded with 3 bands and a Moon right on the limb. The 9.5 Ed gave me 80X so I figured more power couldn’t hurt. I put in the 12mm and 2X Barlow combination for 125X. WOW. I now had a spectacular view and from town with a bright Moon and in a 6″ scope. Jupiter popped detail. Scintillation was minimal. I now had 3 bands with the thinest in the North consecutively getting wider and darker. The Southern dark zone could be seen. I watched as the moon Io disappeared behind the planet. I also noticed on the limb at the dark wide Southern band an odd feature coming into view. After 15 minutes it revealed itself to be the GRS!

Just came in from a last look at Jupiter before it goes behind the trees. 01:40 pm CST. The GRS has now advanced across about 1/3 of the planet. Man it moves fast. It is definitely a fast rotating planet! I gave this info so maybe some one can confirm my sighting.

I hope this report helps many of you that view from light polluted skies. It can be done and with small telescopes. Patience and the right equipment will yield a great viewing experience. Even with my little 6″ F5 a wonderful night of observing can be had right from your drive way with the lights on.

JJ

For the last two weeks I’ve been teaching an astronomy course at Wheaton College’s Science Station in the Black Hills. Last Wednesday evening, July 9, I took my class to visit the Hidden Valley Observatory in Rapid City, which is run by the Black Hills Astronomical Society (http://rap.midco.net/ggladfel/BHAS/). The observatory director, Steve Parker, was kind enough to host our group of eight students plus myself. They showed us their homemade 12.5-inch Newtonian reflector on a German Equatorial Mount housed in their dome, two homemade Dobsonians, a swivel-chair binocular mount, and a Meade My Sky. The observatory resides at St. Martin’s Monastery, on land that is leased by the Society for a nominal fee. Since the Moon was out it was hard to tell how dark the skies really were; lights from Rapid City were evident. The highlight of the evening was a 10:57 PM Iridium flare that reached magnitude -3. I took a photo of the flare with the observatory in the background. The moon is hidden by the tree to the left of center. I didn’t want the moon to overexpose in the 22-second image. Hope you like it!

On 10/31/07 exactly at midnight witch made it 11/1/07 at 01 minutes the elusive constellation Gourdus Spookis appears only for 1 minute on odd years at this time. Intrepid astronomers Dick and John where on hand to capture the moment! With telescopes pointed in the direction of the fleeting asterism we were rewarded with this image. Hope you enjoy!

Comet 17 P / Holmes suddenly brightened in late Oct. 2007 (24th). Watching it over several days showed that it was expanding and in motion towards Mirfak, in the constellation Perseus. I imaged it on a couple of nights and have the results here.

This image was taken on 10/25/07 with a 120mm F 8.3 Orion refractor. Afocal through a 17mm plossel eyepiece and a Fugi Fine Pix camera, zoom at maximum.

This next image was taken on 10/28/07 from same location and equipment. Time was 11:30 pm local. In this case the zoom on the camera was set at minimum for a wider angle shot. Notice a magnitude 9.03 star designated SAO24247, in the background of the coma. I watched this star move from beside the nucleus to the outer edge of the coma over a period of 3 hours.

I will continue to try and post images as long as the comet remains bright enough.

JJ

Latest Image from comet 17 P / Holmes shows the comet is now getting more diffuse and starting to dim. All images are with the same equipment and settings as from above. Image was taken from the Hodgson Observatory on 10/31/07 at 10:20 pm local time. The nucleus and inner coma remain very visible, and is expanding, however the outer coma has expanded so much that it is becoming very diffuse.