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Observation Report
Winters, Sunday, March 18, 2001

by: Gregg Blandin

Here's my first attempt at an observing report:

Sunday evening turned out to be quite reasonable from my backyard location in Winters, CA. despite the light covering of high clouds. Limiting magnitude at the zenith I estimated at just over 5. To minimize the resulting loss of contrast, I limited most of my viewing to the areas around the zenith, mostly Ursa Major. I made a short jaunt into Leo, only to find what I already knew about the more light polluted part of my viewing window.

I'll start with an interesting Double Star which I "ran into" on the way to M82. 13 Ursae Majoris is a bright whitish-blue primary and an orange secondary seperated by 3.9" They split fairly easily at 238 power which was encouraging.

I used a chart I made to find the fainter components of a galaxy group consisting of NGC2854, 2856 and 2857. Those three, the brighter of a group of 6, cross my field at 238X in a straight line. NGC 2854 and 2856 are very close in size and brightness: close to edge-on orientation and at right angles to each other. I could not see any detail in either. NGC 2857 is very round, larger and more diffuse. With magnitudes ranging from magnitude range from 13.8 to 14.3, their different shapes and orientations make a interesting group to observe. Just outside of my field, running roughly parallel to the first group are another, much fainter group of three, embedded in a distinct zig-zag star field. These three in decending order of brightness are UGC5016 (mag 15.24): diffuse face-on, easy with direct vision, CGCG238-53(mag 15.6): appears roughly the same size as UGC5016; averted vision helps here, and CGCG238-54 (mag 15.84): looks slightly larger than the other two and more toward edge-on in orientation (averted vision required). I'm stretching a bit here with averted vision to provide size and shape detail. This will be the faintest galaxy I observe this night. I realize now that the galaxies I observed with averted vision I noted as larger that those with direct vision, even though they actually are smaller. This is probably a rookie mistake (oh, well)

I decided to spend some more time scouring the bowl of the dipper. This area is a delight for all of us poor, unfortunate, go-to deprived souls, who must rely on star-hopping to find there way around the vast universe. Sigh. In a small enclosed square of stars, it's hard to get lost and quite easy to find almost anything in there, but it's easy to mixed up as it rotates around the sky and at least one area contains very similar looking galaxies. I observed three that looked very similar and mixed them up, mainly because of finder allignment, but also because the three looked so similar. NGC 3610, 3642 and IC691 are listed in order of descending brightness. All are face on in orienation and have fairly well defined, off-center stellar cores. I plan to revisit these in darker skies and compare them more closely.

Just down the block from these is a great pair of colliding galaxies (NGC 3690 and IC 694) that appear as one. One appears to have a brighter, more stellar core and more edge-on in orientation. They appear as sort of arc-shaped, alomost like two spiral arms of the same galaxy. I will observe these two again in better skies and hope to log more specific detail.

On the opposite side lies an interesting group of 5 galaxies: NGCs 3998, 3990, 3972, 3977, and 3982. I can fit them all in the field at 138X. The goup is dominated by NGC 3998 and 3990, a pair of unequally bright face-ons, the brighter of which (Mag 10.6) has plenty of structural core detail for veiwing. 3990 is more uniform, dimmer and more diffuse. NGC 3972 (edge-on) and NGC 3977 (face-on) sit on the opposite side of field forming a rough trapezoid shape. Neither of these two shows any detail, but both are easy to see. Off by itself is another reasonably sized face-on, NGC3982 which has a nice stellar core.

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