Posts Made By: Maurice Clark

Hi all.

I see on the CBAT comet page
http://cfa-www.harvard.edu/iau/Ephemerides/Comets/
that the LINEAR survey has picked up another new comet. (2002 O7) The predictions are that this one will also be a good one for small telescopes from the middle of next year. Unfortunately when at its brightest the comet will be on the far side of the sun and so difficult to observe, however northern hemisphere observers should get good views during June and July before the comet disappears into the evening twilight.

Cheers,

Maurice

My new autogiuder (at least....new to me!) arrived and believe it or not but the skies were clear!!!!! For 3 nights running!!!!!!!! Almost unheard of!

The last of the nights was Saturday night and that was the best of all. The limiting magnitude was 6.2 which is as dark as I have seen it from here. (Northfield MN) M31 was the easiest I have seen it with the naked eye since I arrived in the US. The autoguider worked well, which enabled me to just set the camera going and walk away for 45 minutes. Unfortunately the light pollution around campus meant that this was too long exposure. Even for 200 ASA speed film. Next time the weather clears I will have to cut back to about 20 minutes. At my previous location, 45 minutes would still show black sky background on 400 ASA speed flim.

Observed and photographed numerous objects but I will only mention a couple.

Comet Hoenig was very nice in my 10". Quite a bit brighter with more of a condensation in the coma. There was also the hint of a very faint tail visible. This is definately getting better as it approaches perihelion.

Managed to get my first observation of the other bright comet in the morning sky, 2002O6. It was a very bright and easy object, despite having to wait until bright twilight for it to rise over some trees. Very well condensed coma with a faint tail.

As well as visual observation and photography, I was also doing some CCD imaging. The photograph below shows my observing setup. The 2 8" LX200's belong to the college. I use them for CCD imaging, mostly of asteroids. On the right is my 5" f/5 refractor with 3" guidescope. This is the scope I use for photography. The big scope is my 10" dob. This is my scope for visual observing. Needless to say, I am kept quite busy operating 4 scopes at once. Daylight comes all too soon! My wife thinks I am getting a little obsessed!!!

Cheers,

Maurice

PS I will post CCD images of these comets on the CCD forum.

Here is an image of Comet Hoenig I obtained last Saturday night. It is a 3 minute image taken with an SBIG ST-8 and an 8" LX200 at prime focus. The comet has moved a little during the exposure, but it still shows the nice central condensation, the large outer coma and the hint of a faint tail.

Cheers,

Maurice

Here is an image of Comet 2002O6 that I obtained new dawn last Saturday night/Sunday morning. I had to wait some time for the comet to rise above some trees, so it was very bright twilight by the time I was able to take the image.

It is a 60 second image taken with an SBIG ST-8 and an *" LX200 at prime focus.

The comet was very bright and easy to see visually despite the bright twilight. It has a very well condensed coma and a faint tail. At around 7th magnitude, it is visible in binoculars and is well worth getting out and having a look.

Cheers,

Maurice

From the look of the way it is set up, I doubt the owner knows much about telescopes. It would be WAY out of balance, plus the usual claim of unbelievably high magnification!!

Maurice

Hi all.

The autoguider is finally talking to the LX200 so after an observing run when I still had some darkness left I decided to have some fun.

Here is a 5 minute image of NGC 6946. A large, face-on spiral galaxy on the Cepheus-Cygnus border.

Taken with an 8" f/10 and an ST-8, binned 2x2.

Enjoy.

Maurice

This is a 10 minute exposure of NGC 891. Taken with a 8" f/10 LX200 and an ST-8, binned 2x2.

Enjoy.

Maurice

This image is a combination of 3, 1-minure exposures taken with an 8" f/10 LX200 and an ST-8E.

Enjoy.

Maurice

There is a nice bright aurora currently visible from Northfield Minnesota. (lat. ~+45*) It was first visible as a narrow, greenish arc about 20* above the northern horizon. Over the last 45 minutes it has brightened, grown more diffuse, and climbed higher in the sky. It is now quite bright, and reaching about 35* up from the northern horizon. Well worth going out and having a look.

Cheers,

Maurice

There was still some darkness left after I finished imaging asteroids on Tuesday night but the moon had risen so the skies were not really good enough for photography. So I decided to try hooking up the CCD to my 5" refractor.

The scope is an 5" achromat and nearly as old as I am, so there is some residual colour which made me wonder how good the system would focus, especially without an IR blocker in place, but what the heck. Why waste clear skies?

Below is one result. It is a combination of 5 3-minute exposures with an ST-8 (non-E) binned 2x2. I am quite pleased with how it came out. The brighter stars do show some enlargement due to chromatic abberation, but not as much as I expected for such a short focal ratio. I have not yet had the time to measure the field of view, but it appears to be about 1.25* x 1*. It will be interesting to try some nebulae with a red filter.

Comments welcome.

Maurice