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Observing report; March 7, 8 & 9

Started by jeyjey, 03/12/2010 10:33PM
Posted 03/12/2010 10:33PM Opening Post
I got three clear nights in a row earlier this week, and made the most of them:

M82 3/7/2010 20:40 UT; Pickering 8, NELM 5.5, SQM 20.5
400mm Mak-Cass @ 225X

Three angular dustlanes separating two distinct core regions and two outer disk regions. WSW core contains a semi-stellar condensation, while the larger ENE core contains several brighter knots. WSW outer disk somewhat brighter than ESE, and contains a distinct angular feature pointing SW.


NGC3077 3/7/2010 21:10 UT; Pickering 8, NELM 5.5, SQM 20.5
400mm Mak-Cass @ 225X

Very poor condensation with an extended core tapering uniformly to E, somewhat less-so to S and NE, and abruptly to NNW. Somewhat grainy at 150X, giving it more the look of an unresolved globular than a galaxy, and the shape contributes to a cometary appearance at 335X. Interior dust regions not visible.

Nice tight double to NNW and another (outside field) to W. [ADS7611 and ADS7603. Both are about 3.3" separation, and have an interesting history of being confused with each other.]


Arp82 (NGC2535, 2536) 3/7/2010 21:46 UT; Pickering 8, NELM 6, SQM 20.6
400mm Mak-Cass @ 225X

Quite small and dim. Borderline direct/averted vision, but too small to make out any detail at 150X. 235X helps image scale and provides fleeting glimpses of a stellar core (perhaps 25%), but the galaxy is distinctly averted-vision at this exit-pupil. 335X too dim.

235X also reveals second galaxy to SSE [NGC2536], with a similarly fleeting stellar core. It's also visible in averted-vision at 150X when you're looking for it.

This Hickson compact group looked like it might be decidedly difficult in the DSS image, but it turned out to be quite nice:

HCG57 3/7/2010 22:00 UT; Pickering 8, NELM 6, SQM 20.6
400mm Mak-Cass @ 325X

Smudgy area at 150X, with one definite condensation and another probable. 235X confirms both [NGC3750, 3753], with haloes nearly touching, and adds 2 more possibilities to the NW of the first pair. 335X confirms second pair [NGC3746, 3748]. [NGC3745, which lies between them, not seen.]

[Southern-most field star of sketch is likely the core of NGC3751.]


Arp94 (NGC3226, 3227) 3/7/2010 23:01 UT; Pickering 8, NELM 6, SQM 20.7
400mm Mak-Cass @ 225X

Fairly bright pair at 150X. Southern component [NGC3227] with stellar core and N-S elongation, northern [NGC3226] with semi-stellar core and roughly circular shape. Haloes touching, or nearly so. At 235X, southern component shows a dark lane to the E of its core.


NGC2903 3/8/2010 22:41 UT; Pickering 9, NELM 6.5, SQM 20.8
400mm Mak-Cass @ 150X

Elongated moderately condensed core with further mottling surrounded by a large elongated disk. Dark lanes to both sides of core, all along W west edge but only along northern half of E edge. Bright section at NE extend of disk sweeping toward NW. Core brighter than most field stars at 150X.


IC750 3/8/2010 23:00 UT; Pickering 9, NELM 6.5, SQM 20.8
400mm Mak-Cass @ 150X

IC750 shows as a reasonably bright, small streak with a highly condensed, elongated core. IC749 larger and circular, but much dimmer and with no appreciable condensation. A bright field star forms the 3rd member of an interesting trio. [The sketched field star due S of 750 turns out to be the stellar core of IC751.]


Abell 1367 3/8/2010 23:16 UT; Pickering 9, NELM 6.5, SQM 20.8
400mm Mak-Cass @ 110X

Glare of SAO 81972 really nukes this field. I get 4 members at 110X, all with stellar cores, but it isn't very visually rewarding. HCG57 was much more interesting.

NGC4147 3/8/2010 23:40 UT; Pickering 9, NELM 6.5, SQM 20.8
400mm Mak-Cass @ 325X

Clumpy, but no stars resolved at 110X. 235X resolves 4 stars around the periphery while 335X resolves a few in the core. Past that the gains start to tail off; 450X shows a total of perhaps 8 or 10 stars across a milky background.


UGC3697 Integral Sign 3/9/2010 00:10 UT; Pickering 9, NELM 6.5, SQM 20.8
400mm Mak-Cass @ 225X

Poor condensation, roundish. Is this even the right galaxy? [No, it's UGC3714.]

Oh, wait, there's a very dim ghostly streak to NNW of elliptical. I had thought the bent ends would be out of reach, but the whole thing has a nearly uniform brightness, with the curl at the east end perhaps somewhat more detectable than the west. "Detectable" is key here; I can't really say I can "see" any of it, but the narrowness of it seems to be an excellent trigger for the eye's edge detection when sweeping across it. At any rate, it's very easy to reacquire in averted vision, particularly for a target this dim.

Fantastic target: breathtakingly etherial, with an emotional impact similar to NGC891 or the Veil.


M67 3/9/2010 22:16 UT; Pickering 8, NELM 6, SQM 20.7
400mm Mak-Cass @ 110X

Large cluster of about 100 members, mostly of a similar magnitude and color, with one prominent straw-coloured star to the NE edge.

NGC2775 3/9/2010 22:26 UT; Pickering 8, NELM 6, SQM 20.7
400mm Mak-Cass @ 225X

Moderately condensed circular core surrounded by slightly elongated halo. Averted vision shows relatively abrupt edge between core and halo at 235X. The effect is diminished at 335X, where an inner, semi-stellar core appears. Suffers from Drogheda's light bloom.

NGC2859 3/9/2010 22:40 UT; Pickering 8, NELM 6, SQM 20.7
400mm Mak-Cass @ 325X

Tiny, with a semi-stellar core and not much of a halo. Hints of a bar aligned NE-SW.

[I must have been seeing elongation in the inner core. Bar actually runs NNW-SSE, and it and the outer ring are well outside the extent sketched. In fact, the bar runs almost to the dim foreground star to the N, while the outer ring is entirely outside that in radius.]


NGC2964 NGC2968 3/9/2010 23:05 UT; Pickering 8, NELM 6, SQM 20.7
400mm Mak-Cass @ 150X

NGC2964 shows reasonably bright disk but very dim, stellar core. NGC2968 smaller with marginally brighter but semi-stellar core. 2964 irregular in shape with indistinct mottling and a dimmer area to the NE; looks somewhat like a smaller Crab Nebula.


Arp206 NGC3432 3/9/2010 23:30 UT; Pickering 8, NELM 6, SQM 20.7
400mm Mak-Cass @ 150X

Interesting bent-stick of a galaxy with the brighter but somewhat frayed end anchored by a pair of foreground stars and a dimmer, narrower section extending off to the ENE. Very weak condensation just before dimmer section.


NGC3294 3/9/2010 23:45 UT; Pickering 8, NELM 6, SQM 20.7
400mm Mak-Cass @ 225X

Slightly elongated halo (WNW-ESE) of uniform brightness with no core visible at 150X. 235X shows some mottling and a very weak, non-stellar core. 335X shows further mottling, but no more strength to core.

NGC3414 3/9/2010 23:55 UT; Pickering 8, NELM 6, SQM 20.7
400mm Mak-Cass @ 325X

Bright, semi-stellar core with a small halo at 150X. 335X shows more extended halo and a stubby NNE-SSW bar. Pretty similar in the eyepiece to NGC2859.

Cheers,
-- Jeff.
Posted 03/12/2010 10:49PM #1
Very nice! Great descriptions and top-notch sketches!

Can you comment on your sketching technique? How much do you do at the eyepiece itself, and how much do you fill in later? Are you getting all those field stars down while in the field yourself? No doubt it helps to have a driven scope, unlike us push-to types. And how do you control eye adaptation--I'm always challenged, even with a very dim red LED light, to look at my sketch and at then look back at the target, so much so that I often wind up sketching with my left eye open only, so that my right eye stays adapted.

--george

George Golitzin
Posted 03/13/2010 02:05AM #2
Jeff,

Thank you for the report and sketches, you have caught how galaxies look at the eyepiece extremely well. Congratulations on your talent and skills.

Rick

8" Zhumell Dob
90mm f11 achro refractor
4-1/2 f4 rich field newt reflector
Posted 03/13/2010 07:25AM #3
Posted 03/13/2010 04:36PM #4
Really nice indeed, thanks for posting smile

-Magnus
Posted 03/15/2010 12:52AM #5
Jeff

What size sketchbook are you using?
What size circle?

I use a 5.5 x 8.5" book, six 2-inch circles drawn with a 2" eyepiece skirt. Im thinking two 4-inch circles per page may be better.

John