First Light report with AD8 Dobsonian Telescope

March 17, 2012: First Light Report
Apertura AD8 8" Dobsonian Telescope

There are several vendors offering essentially identical GSO instruments (from a Taiwanese company called Guan Sheng Optical).  These vendor's main differences are their customer service and the included package of accessories.  My favorite available combo was offered by Opticsmart, a new company with a good reputation for customer service.

My new scope arrived Thursday, Mar 15, 2012.  It is an 8" Dobsonian-mount reflector telescope, basically a 4 ft long empty tube with an 8" inside diameter and an 8" mirror at the bottom end.  This OTA (Optical Tube Assembly) sits on a wooden rocker base such that it swivels smoothly up/down and left/right.  For you propeller-heads out there, this scope came in a bundle with a 2" 30mm wide-angle EP (eye-piece), and a 9mm (higher power) EP.  Also included was a nice right-angle, 8x-power spotting scope, with cross-hairs for centering the view, a laser-collimator, used to finely adjust the scope's mirrors, and an upgrade to a 2" dual-speed focuser. (trust me, that's good) 

 

I carried the two heavy Fedex packages inside from the porch, and opened them up - holy cow this thing is big!  The base required assembly, and the tube also needed some set-up.  Though the manual was fairly clear, during this process I called Opticsmart and pestered both Rex and Dave with a few questions each.  They were patient and happy to help, and the whole scope-building process took me a bit over an hour.  The new telescope weighs 55 lbs or so, but the OTA comes right off the base, and I mostly carry it in two trips.  My old scope was a serious little 4.5 inch "Dob", but, as you can see in the pic below, is dwarfed by the 8" model.

Unfortunately that first night was mostly overcast, acquainting me with the telescope-buyer's curse that acquisition of new astronomy gear causes cloudiness, usually in proportion to the price of said gear.  I did get a ten minute window and hauled the thing outside for quick views of Jupiter through thin clouds, Orion Nebula (which looked great in my new wide-angle lens), and Mars, also cloud-veiled.  I don't really count this quick session as my official "first-light" with this telescope.  The main thing I learned was how heavy the damn thing is.

Last night was blessedly clear, however, and I took this behemoth out and really put it through its paces.  First I set up in my backyard, before sunset, and looked at Venus, currently at half-phase (viewed from Earth, Venus' shape varies like that of our moon).  The seeing was quite good and a medium-high power showed a fairly crisp semi-circle surprisingly big in my eye-piece.  Soon, dusk brought out nearby Jupiter, where I sampled all the various magnification combos.  I have seven different "powers" available, comprised of the two new EPs, (2" 30mm wide-angle and 1.25" 9mm), two other 1.25" EPs, (17mm and 6mm) which came with my other scope, and a Barlow lens, which doubles the power of any 1.25" EP.  

Viewing Jupiter, I enjoyed a big, reddish disc with two clear, dark atmospheric bands, and Jupiter's four Galilean moons blazing nearby.  This was drastically more than I've seen through my little 4.5" scope, which easily shows those moons, but, at best, has shown a small black and white disk with barely visible bands.  I smiled broadly and dragged my partner, Rose, outside to see it, who favored me with a nice "wow"!  I took a couple snapshots with a little digital camera.  The left side is quick shutter, the right was auto, which clearly overexposed and the shutterspeed exceeded my steadiness.

OK, a good start, but I had bigger plans.

After dinner I prepared for a long viewing session and drove about 10 minutes into the hills, away from street and city lights, to my friend Paul's backyard, who was good enough to turn off most of the house lights and do some quick poop-scooping for our viewing session.  After three trips from car to backyard (scope-base, tube, and accessory/refreshments - whew!), we were ready to go.

I gave Paul a quick tour.  We started with M42, Orion Nebula.  Here I again ran through my eye-piece combos, enjoying both the wider views and the close-ups.  We looked at Pleiades, which is simply breathtaking through the 30mm EP, and then Mizar, Mars, and some open cluster star formations in the vicinity of Sirius, (M41 and M50), favorites which I can find quickly.  

Then came a definitive moment: I wanted to see how this scope performs looking for galaxies, which, because of their incredible distance and hazy, diffuse light, are among the hardest objects to find.  I've seen the Whirlpool Galaxy (M51) a couple times with my old scope, once even from my backyard, but I've never seen more than an indistinct smudge.  I pointed the spotter-scope near Alkaid in the big dipper, at the general area where I thought it would be, switched to the main scope, and BLAM!  The galaxy was obvious, much brighter than I'd ever seen, showing the definitive two galactic nuclei and big-blob-little-blob snowman shape.  It was time for my own "wow"!   The wide-angle 2" EP is incredible for galaxy-hunting, showing wide swaths across the stars, and I realized, a) I wasn't going to sleep much this night, and, b) I didn't care.  A quick trip to the top of the dipper showed a great view of Bode's Nebulea, M81 & M82, which I'd also seen before, but now they were way more blatant and clear to see.

I realized that it was time to look at Saturn, which I'd been eagerly anticipating, especially after seeing how great Jupiter looked in the 8-incher.  I also knew it would totally blow Paul away, as it does with everyone upon first looking.  I was right.  I set up the scope on Saturn, stuck in a fairly high-mag 9mm EP, then passed the first view to him with a big grin:  "OK, dude...Check this out."  He was screaming and jumping around for five minutes, literally.  After we settled down and experimented with different EPs, we could see five moons!  It was amazing, and by itself, easily worth the price of admission.

My next target was M63, the Sunflower Galaxy, out past the Whirlpool Galaxy, but in the same area.  With my Pocket Star Atlas, it took me about 20 seconds of looking until, to my delight, I had it in view.  This was the first DSO (deep space object) of the night that I'd never seen before and I felt the quiet pride that comes with a successful sequence of star-hops, and a growing anticipation, wondering what other marvels I'd find in tonight's clear sky.  On to the Leo galaxies!

I knew that galaxies M95, M96, and M105 are all in a small part of the sky between Regulus and Chertan, in the Leo constellation, which also happens to be Mars' current location.  Using my sky atlas, I spent some time slewing across the area with no luck, until I happened to sweep over to Mars.  Thinking I was off-track, I was about to reset when a fuzzy patch caught my eye.  Sure enough, M95 was in the same field of view as Mars, and, so was M96.  It was easier to see the galaxies at the edge of the field, to take out Mars' bright glare.  A little more orienting quickly brought me to M105, as well, right nearby.  After another quick set of hops and I was gaping at M65 and M66, over closer to Chertan.  Wow, five new Messier galaxies in a few minutes' span.  Very cool!

Moving back over near the big dipper again, I found a fuzzy patch nearby which turned out to be M97, the Owl Nebula, and a quick retreat toward the star Merak brought the galaxy M108 into view.  Sweet!

Over to Spica, I went hunting for an old nemesis, the Sombrero Galaxy, M104.  I may have found it once before in very dark skies, with my small scope, but I was never really sure I'd seen it.  I found (or thought I did) the triangle of stars in which to look and was scanning back and forth for all I was worth.  I spent probably 30 minutes trying to match what I was seeing with my eyes, the spotter and the 30mm EP, with the points in the star atlas, convincing myself the patterns I was seeing matched the sky-map.  Eventually, though, I realized I was mismatching the sky to the map, and that's why I couldn't find the Sombrero.  Duh!  After realizing my mistake, I found the correct area in which to search, and immediately found this troublesome little fuzz-patch.  Woohoo!!  I was on a roll now!

Moving the spotter scope in Virgo and checking the star atlas, I was little intimidated by the number of galactic targets.  I searched for M61, which is a bit dimmer than most I'd been seeking, but I eventually found it and M60 on the other side of the galactic cluster.  With a couple more star-hops I'd collected the lovely globular cluster M53, and the Black-Eye Galaxy, M64.

It was really late now - I'd been star-watching from 9:30PM to 2:30AM straight.  I was euphoric from the fantastic session, but I needed to sleep a few hours.  I packed up, schlepped everything back to the car, and drove home, just buzzing with my success.  Once again, "wow"!