Report - First Observation Session... (In a long time)

Dr Pepper

Hi Folks,

Just bought Peanut's DTG 8.75" Dobsonian (big refractor) on Monday evening and was lucky enough to have a nice clear night last night with Venus, Saturn and the Moon all making an appearance. Unfortunately, there are tall trees all around my garden so Venus is not possible to view unless I get out by 6:30 or 7 (which I didn't).

Moon

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This was my first target. It was suprisingly easy to find in the scope (took me about 20 seconds - This may sound ridiculous to non-astronomers but, with my old telescope, it used to be a nightmare to find anything). I was using a 10mm eyepiece first and the view was spectacular. The moon took up most of the viewing area with good detail. There did seem to be a constant shimmering effect though. I put this down to the viewing angle with the atmosphere because the moon was fairly low in the sky but if anybody here has another explaination, I'd love to know. I suppose a comparison with an observation of the Moon while it's high in the sky will confirm (or not) my theory. I switched to the 25mm after a while and was once again blown away! The full viewing area was taken up by just about a quarter of the Moon and the detail was amazing. Saw the American flag and all!

Saturn

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Saturn was in an unfamiliar part of the sky for me so it took a printout from this site (which I find quite useful when you get used to it*) and close study of star charts to identify it. Suprisingly enough, didn't take me all that long to find this in the scope either (1 or 2 minutes - probably just beginners luck).. The views with the 10mm (left) and 25mm were similar to the pics below and I could also see 3 tiny dots in the vacinity of the planet which I suspect may have been 3 of the bigger moons. I'd like to find out (on the net) where each of the moons actually are at any particlar time and compare that info to my observations to identify which ones I'm looking at. Anybody know of a good source for this info?



Saturn is out all night again tonight (not suprisingly) so I should be continuing my examination. I'm going to try and get out at 6:30 or 7 and catch Venus before she disappears below those damn trees (or else just go to the local running track/GAA pitch for extended viewing).

Anyway, thoroughly enjoyed the first test-run of my new scope.. All observations/advice appreciated!

*Anybody have recommendations for a better site/program for this data?

murphyme

Hi,

You could try heavens-above.com for the sky chart.

I found this http://pds-rings.seti.org/tools/ for generating
plots of the position of the moons of Saturn.

Michael.

Dr Pepper

Cool, that planetary moons website is amazing (It's sickening how clever some people are sometimes!!). I generated this picture of Saturn at my approximate viewing time last and location night and it corresponds to what I saw. The moons I could see were Titan, Rhea and Dione (except my image was upside-down compared to the generated one!). Couldn't see the smaller ones.
Heavens Above also looks very useful too. I love their Solar System chart. I've been looking for something like that lately..
Thanks Michael!

More questions: :rolleyes:
- Is there any point in my getting a bigger eye-piece? I have a 10mm and a 25mm. Will the magnification be twice as good again if I get a 50mm eye-piece or will this just be distorted?
- Will I be able to see nebulae or galaxies reasonably well with this scope? If so, can anyone recommend a good one/two to start with? (which are currently in our sky... and relatively easy to find!)

murphyme

You could try a 5mm eyepiece. Alternatively you could get a two/three by barlow. This will divide the focal length of your two eye pieces by 2 or 3 doubling or trebling the magnification.

Try to borrow one first just to make you can track objects using a dob. I've never used one so I don't know how easy or otherwise it is to track at high magnification with one.

Michael.