Telescope Reviews: Stillwell + The Orange Crush--Obs. Report 7/1/2008

The past several months have been nothing but frustrating. Ever since I made a trip out to Big Bend National Park in February, we've been paying for it ever since with bad luck, bad timing, and bad weather. That *FINALLY* changed this past Tuesday night, when Phil Hoyle, Dave Miller and I went down to the Stillwell site in northern Coshocton County, Ohio.

I was towing along my usual glass suspects (25x100s / 16" f/4.5 truss dob), but this time around we had some opportunities to check out some new toys under dark skies. For instance, Dave brought down his 106mm Tak...106mm Tak...

...

As for yours truly, I brought down a new eyepiece--the new Celestron 23mm Axiom LX. Weighing around 2 lbs. (don't believe the 17 oz. listing on Celestron's website), this baby's big, but it's worth it if your scope doesn't have balance issues. With a distinct orange Celestron decal on the front, I affectionately call it "The Orange Crush", though to be fair, most of the EP's outside is metallic, not orange.

We had some passing cirrus through the first half of the night, but they never became that all-encompassing veil that frustrates deep-sky observers, so all-in-all it wasn't fabulous transparency-wise, but it was good enough. I was largely interested in testing out the new EP, so I didn't bag too many new objects, but there were a few memorable observations. Here's the rundown--

M11--Indescribably beautiful with the Orange Crush. The low-power view of this cluster alone made the trip worthwhile. That was just the start.

M13--At 79X, a surprising amount of loops and structure in the cluster was evident. Further examination of the star field revealed a TFOV of about 1.09-deg. My mirror is a 15.85", 71.15"-focal length mirror, so the TFOV should be 1.04-deg. I won't complain about having 5% more FOV, though, in a low-power EP!

Coma was indeed evident in the outermost portion of the FOV (this is an ultrawide 23mm in a 16" f/4.5 w/o coma correction), but the stars at the edge were stars, not mushed out with off-axis astigmatism--a very encouraging sign. M13's stars were still resolvable at the field stop.

NGC 4236--Now here is where a 5.1mm exit pupil comes in handy. My 13T6 Nagler yields a 2.9mm exit pupil and about 140X; it's a good, all-purpose "30-.06" ocular, especially for galaxies. But here the ridiculously-low surface brightness requires a really low-power view, and the surplus JDAM munition--ERRRR--Axiom came through beautifully here; the object was obvious, with fleeting detail visible on the ends.

M27--This was where it became painfully obvious that I made a serious oversight when I bought the 23mm Axiom. It showed the transverse "football" nebulosity in all its glory, but...of all times, it wasn't until then that it occurred to me "you know, if I just put an O-III filter on this, it'll--oh, that's right. I don't HAVE any 2" filters!

Dave came to the rescue with a 22mm LVW, which accepted my 1.25" O-III filter.

M8--Dave's 22LVW + O-III combination yielded a 0.79-deg TFOV that was just chock-full of nebulosity and dust.

M17--Dave's 22LVW was a bit low in power, but the 13T6 + O-III combination yielded a view that was astounding in dust detail at the junction of the "checkmark".

NGC 6888 (The Crescent Nebula)--this is where I threw caution to the wind. I could easily make it out in the 23Ax, but I knew the Crescent Nebula is one of those objects that just leaps out at you with O-III filtration. I decided to remove my eyeglasses and (carefully!!) bring the O-III filter up close to the eye lens. I only had ~50 deg AFOV, of course, but the all the tendrils of nebulosity I could see convinced me my next purchase is a 2" O-III filter.

Without a 2" O-III filter, I decided to go cluster hunting in Cassiopeia, and my search was very rewarding.

M52 + Czernik 43--This looked like a looser version of the Double Cluster. C43's stars were still easily resolvable in the 25x100s, to the tune of at least 30 of them in the binos. It's too bad it's got such an obscure designation. If supplied with a reassuring "M" or "NGC" prefix, it would be a much more popular object.

NGC 7635 (Bubble Nebula)--This was completely unrewarding, other to see if it could be detected. The 23Ax provided the best view with its bright exit pupil, but visually, NGC 7635 is uninteresting.

Naturally, I had to see if I could detect it in the 25x100s. Ahhh...nope.

NGC 7789--This one's my all-time favorite open cluster for the 25x100s, but telescopes just don't seem to do it justice. The 16" + 23mm Ax did a good job of properly framing the cluster w/o having too much power. The result was a squashed, elliptical, very rich cluster with distinct dark (starless) lanes throughout.

NGC 7510 + King 19--Another "Double Cluster" Wannabe, only this time the fainter cluster (King 19) wasn't a good deep-sky object in its own right.

Far different story for NGC 7510. This thing looks like either a wedge or an arrowhead, with a VERY distinct boundary all throughout the cluster. A highly, highly recommended sight.

Jupiter--The 9T6 Nagler had a good view of Jove by 2 a.m.; this is about 200X in my scope and cloud belt detail was really pouring in. I'm not a planetary observer at all but I couldn't help but marvel at it.

Of course, in this process I'm violating several laws of Dob Land. First, I'm throwing a 16" Dob at a planet, which is kind of like using an ax to slice butter. It's an f/4.5, so definitely no "planet killer" labels here. Worse offense still, it didn't have a Zambuto mirror (oh, the horror! The Horror!)

NGC 6445--I had never seen this gorgeous planetary nebula in Sagittarius before, and I sincerely wondered why. Finding M23 is 2/3 the battle, and it's not a hard one at that. Even at low power two distinct lobes can be seen.

But it's not like the Dumbbell Nebula. Picture laying an egg on its side. Now add another sideways-pointing egg directly on top (and somehow try to maintain balance). Now make the edges fuzzy. That's NGC 6445. The 9T6 provided the most pleasing view at 200X, and it has quickly become on of my favorite PN's.

As we got toward 3 a.m., I was starting to feel the effects of exhaustion and drowsiness. I started to confine myself to brighter targets, but there were two that just left an emphatic mark on this night.

Double Cluster in Perseus--I can't put into words what this looks like in the 16" with the 23mm Axiom. The entire complex EASILY fits in the FOV, and the fact that the exit pupil is 5.1 vs. 6.9 with a 31T5 makes for a more pleasing, downright hypnotic view, including a vivid red star lying between the two clusters.

It was upon seeing this that I couldn't help but I let out a hearty Jabba-The-Hut laugh ("OHH HO HO HO!!! Solo!! OHH HO HO HO...")

M31 and friends--The 23Ax had juuuuust enough FOV to encompass M31 + dust lanes, M32 and M110. I can't wait until the fall to see it higher up in the sky--if gas isn't being rationed because it hit $10/gallon, that is.

By 4 a.m., I was completely exhausted, and fell asleep in my PT Cruiser, with the knowledge that I had finally spent a night communing with heavens the way it was meant to be.

Clear Skies,
Phil

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"Why suffer from insanity when you can revel in it?"

Wilderness Center Astronomy Club member since 1995
ICQ Comet Observer Code: CRE01
*****
16" f/4.5 Truss Dobsonian (FOR SALE!!)
Orion 120mm ST Refractor
23mm Axiom LX
13mm Nagler Type 6
9mm Nagler Type 6
1.75X Siebert Barlow
*****