Monday, December 7, 2015

OR, Fremont Peak, 2/15/2015

I drove down to the FPOA area with fellow SJAAer Sizhuang Liu, who was looking forward to an all nighter, as was I. We arrived around 5pm and set up our scopes under cloudy skies; I was full of confidence they would dissipate by nightfall. It took a couple hours longer for the clouds to finally clear, and we had a good night with very good seeing and average transparency; SQML was from 20.3-20.9.

I enjoyed getting to know Sizhuang during the wait; he shared stories of his and his friends’ observing adventures in China. The next time I think the “hassle factor” to get out and observe is too high, I’ll think of Sizhuang and his friends, carrying refractors in their backpacks and a 10” reflector and dobsonian mount by hand for hours on subways, busses, and overpriced rural taxis up washed-out narrow mountain roads just to get to a NELM 6.0 sky. Such dedication, and fun!

Galaxy season has started in earnest and they dominated my observations, all with a 20” f5.25, highlights as follows:

NGC 3344, Leo, 205x: Bright, easily found DV, AV helped pop out hints of spiral structure, especially an arm starting south of the stellar nucleus and hooking west, and an opposite member starting north and hooking east. 3’x4’ visible, longer E-E. Three close faint foreground stars to east, two of which are superimposed on the halo.

NGC 3395 & 3396. LMi, interacting galaxies, 205x NGC 3395 is fairly bright, with mottled halo texture. Orientated NNE-SSW, 1.5’ x 0.7’ visible, with a distinct backwards “S” shape, the southern arm reaching out towards 3396. NGC 3396 is a little dimmer than its companion, elongated 3:1, 1’ long major axis visible, WNW-ESE.

NGC 3190, 3193, & 3185, Leo. 205x I went seeking 3190 & 3193, but discovered 3185 in the same FOV. 3190 was the brightest of a line of three galaxies. It was a long edge on, 4:1 NW-SE with a stellar nucleus, about 2’x0.5” visible, with a darkening in the halo to the SW. 3193 was to the NE, bright & easily seen, roundish and small, with a stellar nucleus. 3185 was to the SW, the dimmest of the three, bright nucleus with a diffuse halo, orientated NW-SE. Had I been more diligent, I might’ve also seen NGC 3187 to the NW of 3190, which I see on Aladin this morning and is a striking spiral. I will need to try this one again.

NGC 3184, UMa, face on spiral, 205x Large, fairly bright, stellar nucleus with spiral structure apparent with AV. There is a foreground star involved in the Western arm [this is actually NGC 3181, an HII region of 3184] and another one in the northern portion [this is a star]. About 3.5’ visible E-W and 4.0’ N-S. NGC 3521, Leo, Spiral Gx 205x Large object easy in DV. Fully 5’x2’ elongated NNW-SSE. Bright elongated core seems to float in a swirling cloud – remarkable three dimensional effect. Halo is mottled and cloudy, strongly suggesting spiral structures. Diffuse edges extend far out especially to NE.

NGC 4666 w/ supernova ASASSN-14Ip: This was my third observation of this SN, first on 12/26/14, and second on 1/24/15. At 205x, the supernova was only held 50% with direct vision but obvious just to the north and east of the nucleus, close enough one might confuse the two. In December I estimated (and reports confirmed) 11-12th magnitude; January I estimated 13th. As the SN was still about as bright as the southward pointing star in the close trio of stars to the SW of NGC 4666, it is likely the 13th still or a little dimmer. The last published report I find online is 13.1 magnitude, having fallen from the peak of 11.7 the end of December. Catch this one before it’s too dim!

Omega Centauri, GC When I first saw this last year, it took an arduous star hop from Corvus, since I was unfamiliar with this constellation. I was about to repeat this until Sizhuang showed me the naked eye star patterns to follow, and where to scan with the finder – and I quickly acquired the target. At 121x it is large, filling the 0.7* FOV, with many ragged loops and chains of stars, with many, many stars resolved and many, many more a glittering dust behind. I needed to sit on the ground to view this from the eyepiece.

NGC 5128 / Centaurus A, 205x The famous radio / starburst galaxy. At this magnification it nearly filled the 0.5* FOV, a dim glow elongated ~3:1 NE-SE with a very obvious and wide dust lane running NW-SE, which with AV showed ragged edges. A faint star was at the SW edge of the dust lane. This was 5* higher than Omega Centauri, so I only had to kneel to see this one!

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