Earlier this week we had an excellent night at the Cherry Springs dark sky park in Pennsylvania - even if we could not last much past 2 am because of the cold. It was -18 C (0 F) and completely clear. The transparency was forecast above average by the Clear Sky Clock and was very good indeed. With my SQM-L I measured 21.65 mag/sq arcsec overhead, so the site seemed to be back into its usual range after what seemed like brightening in the second half of last year. I spent most of my time in Cancer and later in Canes Venatici pursuing objects from the complete Herschel catalog. The transcriptions will be published in due course on my blog (link at end of post). Below are some of the most interesting objects from just Cancer. I was observing with my 12" LX200GPS SCT and 8-24 mm Pentax zoom (nominally 125-375x). The thumbnail pictures are DSS2.

Arp 83 DSS2.jpg NGC 2648. Arp 83. An interacting pair with a CGCG galaxy. The NGC component has a faint starlike nucleus. Only the bright core is visible, not the arms. The CGCG companion is very thin but as long as the bright core of the NGC component. About one-third [as wide as it is long].


Arp 163 DSS.jpg NGC 2672. Arp 163. A very close, practically touching pair of galaxies. The main component is fairly bright, concentrated, possibly with a starlike nucleus. The smaller component is just off its edge, diffuse and very slightly elongated. Farther in almost the same direction from the main component is a field star. The star, the small component and the large component form an equilateral triangle with their centers.


NGC 2678 DSS.jpg NGC 2678. An asterism, Herschel object class VIII. Fills the field at 24 mm [setting of the 8-24 mm Pentax zoom]. Consists of a very extended group of four bright stars and four faint ones that extends across the field and a much more compact group of three bright stars and three faint stars in the form of intersecting triangles.


NGC 2679 DSS.jpg NGC 2679. At high magnification appears to be double. The main component is concentrated to the center and has faint extensions. It is small, and an even smaller component is immediately off its edge, clearly separated. In the small component, a starlike core is intermittently visible.


NGC 2744 DSS.jpg NGC 2744. Edges diffuse, concentrated diffuse core. Slightly elongated 2x1 toward what appears to be a slightly detached patch. On the same side of the galaxy is a star. The star is clearly separated from the diffuse edge of the main component.


NGC 2796 DSS.jpg NGC 2796. The galaxy is visible at low magnification of the zoom. At high magnification its slight elongation and two non-NGC components are visible. Next to one of them is a field star.


NGC 2802-2803 DSS.jpg NGC 2802 and 2803 are a very distant close pair of galaxies. The resolution is somewhat uncertain even at high magnification, although there appear to be two extremely diffuse and faint round components that are separated by a little more than their diameter, and the overall axis of the system is nearly parallel to the segment between two nearby stars. The two galaxies and the two stars form an extended trapezium.


NGC 2843 DSS.jpg NGC 2843. A small and diffuse round galaxy. On its edge is a faint star. A bright star is on the edge of the field at high magnification. Another field star is on the other edge of the field, much fainter. The galaxy is clearly visible and resolved from the star on its edge only at high magnification. [This galaxy is remarkable for its distance - more than 700 Mly - and contention that Herschel could not see such a faint object. While it is not impossible that he meant to catalog something else in the area, my observation is more proof, if one was ever needed, that Herschel most certainly would be able to see it.]