by Albert Highe
The forecasts indicated the clear skies would end by the time the weekend arrived. Consequently, on Thursday I decided to take my 16" f/4.5 scope to Michelle's Plettstone in the Sierra Foothills near Mariposa. You can see some images of the new scope at http://ultralightscopes.com/16MarkV.htm.
The skies were clear and the temperatures were in the mid-60's during most of the drive. By 7PM, the temperature at Plettstone had dropped to 41°F with a relative humidity of 80%. Temperatures continued to drop during the night, reaching 35°F at 2AM. The relative humidity peaked at 90% around 9PM, but dropped to 71% at 10PM, and finished up at 81% at 2AM. Although it was cold, there was no wind and no dew. Wearing my new expedition-weight thermal underwear, all but my toes were comfortable. Seeing started out good. Stars were crisp in the 7mm Nagler T6 (261X). I could hold six stars in the Trapezium easily and continuously. By Midnight, seeing started to deteriorate and I stepped down to the 9mm Nagler T6 (203X).
Temperature and humidity were similar on Friday except some high thin clouds periodically passed through, interrupting our observing. For the first time I tried some toe warmers. I was surprised and pleased how well they worked.
I don't want to list all the objects I observed during the two nights (>80 on Thursday and >60 on Friday). For the most part, I observed faint NGC objects that failed to make most observing lists. Generally, they are dim smudges that show minimal detail. Here are some selected observations.
Three NGC galaxies lie within a 12' circle, all visible within the f.o.v. of the 7mm Nagler.
NGC 1221 (mag 13.5, 1.3' x 0.5') Faintest of the group. Noticeably elongated. Slightly brighter core visible steadily with averted vision.
NGC 1223 (13.4, 1.2' x1.0') 7' N of N1221. Appears to be brightest and largest of the group. Stellar core visible with direct vision. Larger nearly circular outline steadily visible with averted vision.
NGC 1225 (14.0, 1.2' x 0.6') 8' ENE of N1223. Oval outline with slightly brighter core visible steadily with averted vision.
IC 1866 (13.9, 1.0' x 0.7') 9' SSW of N1221. Small oval with slightly brighter core visible steadily with averted vision.
Notable because it is the only NGC object I searched for but did not find during the two nights. DSS image shows a low surface brightness face-on galaxy.
NGC 1320 (12.5, 1.9' x 0.6') Can see bright stellar core with direct vision. Averted vision hints at elongated halo. Appears to be second brightest in the group.
NGC 1321 (13.3, 0.9' x 0.6') Brightest galaxy in the group. Can see the brighter core with direct vision.
NGC 1322 (13.4, 1.1' x 0.9') Bright stellar core visible with direct vision. Appears to be third brightest.
NGC 1323 (15.1, 0.9' x 0.4') Much smaller than other group members. Appears to be a slightly hazy star with averted vision.
NGC 1417 (12.1, 2.3' x 1.2') Moderate size, fairly bright oval with bright core. Can see with direct vision. Lies between the following two galaxies.
NGC 1418 (13.6, 1.0' x 0.6') Lies at the E end of the line. Smaller oval with brighter core. Also see with direct vision.
IC 344 (14.2, 1.0' x 0.5') Lies at the W end, nearly in line with the above two galaxies. Near uniform surface brightness oval. Can hold 95% of the time with averted vision.
NGC 1397 (13.7, 1.7' x 1.2') 25' W of IC344. Appears as small oval with smaller, slighter brighter central area. Can hold steadily with averted vision.
NGC 1424 (13.8, 1.7' x 0.5')14' E of NGC 1418. Appears as oval with near uniform brightness. Can hold with averted vision 95% of the time.
NGC 1441 (12.9, 1.6' x 0.6') Westernmost galaxy of the group. Appears to have larger outline with averted vision, but core is dimmer and less distinct.
NGC 1449 (13.5, 0.8' x 0.5') 6' ENE of N1441
NGC 1451 (13.3, 0.8' x 0.6') 6' ESE of N1441
NGC 1409 (13.8, 0.9' x 0.7') Small circular patch with faint stellar core. Can just hold core with direct vision. Halo is visible 100% of the time with averted vision.
NGC 1410 (14.3, 0.7' x 0.6') After several minutes at 261X, I began to detect a second tiny stellar nucleus approximately 15 arc-seconds NNE of NGC 1409. Seeing was pretty steady, so I increased the magnification to 366X (5mm Nagler T6). With the galaxies more widely separated, I could hold see both galaxies simultaneously with averted vision. Averted vision also revealed a small circular haze around the faint stellar core of N1410 approximately 25% of the time. NGC 1409 also was more obvious.
NGC 2211 (12.7, 1.4' x 0.7') Hold bright, stellar core with direct vision. Hold moderate size oval steadily with averted vision.
NGC 2212 (13.4, 1.5' x 0.8') Less than 2' NE of N2211. Smaller and considerably fainter. Hold with averted vision 75% of the time.
Sh2-301 (10.5, 8' x 7') This object is listed on the "Best of Deep Sky Objects Not in the NGC" list by the Saguaro Astronomy club. Well, Guillermo and I were unimpressed. I could tell a faint haze was present with the 13mm Nagler T6 (140X). A UHC filter improved contrast, revealing a squarish nebula with a wispy arm along the western edge. Sky transparency may have degraded. I'll have to take another look. Anyone else have observations of this object?
Three small oval galaxies lying within same f.o.v. of 7mm Nagler.
NGC 2600 (14.2, 1.2' x 0.3') Westernmost galaxy in the group and the second brightest. Can hold this small oval steadily with averted vision.
NGC 2602 (14.7, 0.4' x 0.2') 7' NNE of N2600. Faintest and smallest galaxy in the group. Can hold 80% of the time with averted vision.
NGC 2603 (14.3, 0.7' x 0.3') 7' ENE of N2600. Brightest of the group. Can just detect brighter central area with direct vision. Can hold steadily small oval with averted vision. Uranometria labels this object as N2603, but S. Gottlieb and NED label it as N2606.
NGC 2692 (13.3, 1.3' x 0.5') Small oval held steadily with averted vision. Bright central area visible with direct vision.
UGC 4671 (12.7, 1.5' x 1.3') 4' NW from N2692. Appears as smaller oval than N2692. Very small bright core visible with direct vision.
UGC 4690 (13.9, 1.1' x 0.5') 13' NE from N2692
Pair of close galaxies approximately 12' SSW from N2692, with a separation of 4'.
MCG+9-15-51 (14.2, 0.6' x 0.6')
MCG+9-15-52 (14.5, 0.5' x 0.4')
Both galaxies show brighter cores, barely visible with direct vision. Small haloes visible steadily with averted vision.
NGC 2693 (11.9, 2.6' x 1.8') Very bright core, visible with direct vision. Moderately large slightly oval hazy halo visible with averted vision. No distinct outline.
NGC 2694 (14.4, 1.2' x 1.2') 1' S of above. Much fainter and smaller fuzz ball. Can hold steadily with averted vision. Stellar core?
NGC 2739 (14.7, 0.8' x 0.3') Hold 90% of the time with averted vision.
NGC 2740 (14.0, 0.9' x 0.7') 1' SSE of above. Appears slightly larger, with more uniform brightness. Hold 80% of the time with averted vision.
NGC 2959 (12.8, 1.3' x 1.3') Bright core visible directly. Moderate size circular halo visible steadily with averted vision.
NGC 2961 (14.7, 0.7' x 0.2') Lies approximately 1.5' NE of above. Much smaller and fainter oval. Hold 95% of the time with averted vision.
Aligned roughly E-W.
NGC 2814 (13.7, 1.2' x0.3') Westernmost galaxy, oriented NS. Noticeably elongated. Hold steadily with averted vision.
NGC 2820 (12.8, 4.1' x 0.5') 3.5' E of N2814. Much larger and brighter. Highly elongated. Oriented WSW-ENE. Near uniform brightness. Hold steadily with averted vision.
IC 2458 (15.0, 0.5' x 0.2') Very much smaller and faint oval lying between the above two galaxies. Hold with averted vision 75% of the time.
Armed with Richard Crisp's image (thanks for posting), I went looking for the recently discovered supernova in M100. The field was framed nicely in the 13mm Nagler T6 (140X). The supernova appeared as a faint star approximately 1' S of the core. I could hold it steadily at this magnification. Its brightness appeared to be similar to the two nearby field stars that lie on either side (GSC1445:2391 and GSC1445:2507).
Thanks again Michelle for allowing me to visit mid-week.
Posted on sf-bay-tac Mar 03, 2006 02:31:16 PT
Converted by report.pm 1.2 Mar 05, 2006 20:12:59 PT