By Steve Coe
Here we are at our second pass through the deep sky objects in Cassiopeia. This Fall constellation really is quite obvious under dark skies, an “M” or “W” shape in the Milky Way. I included four objects this time, one nebula and three open clusters. There is lots of detail to see in all of them.
NGC 281 is a nebula that really responds to the UHC filter. Using a 4" f/6 refractor and a 14mm eyepiece, the nebula is just seen as a faint glow without a filter, there are 6 stars involved. Adding the UHC makes a big difference in the contrast of this nebula. There are only 3 stars involved with the filter in place, but the nebula now takes on the "Pac-man" shape. It is still a low surface brightness nebula with the small scope, but the filter makes all the difference.
With a 13" scope at 100X with the UHC filter, it is bright, large, irregularly round, little brighter middle, counted 28 stars in nebula, several very faint. Nebula fills entire field with very faint nebula at the edges. There are several dark lanes in the nebulosity--one cuts through the PacMan "mouth". Without the UHC the central nebula is about the same, but the faint outer portions of the nebula are gone. I like the view with the UHC better, a nice, contrasty view of the Pacman. Still some stars involved, even with the UHC.
NGC 281 13 inch
100X UHC filter
NGC 457 is an open cluster that has within it a bright, naked eye star, Phi Cas. Using a 6" f/6 Maksutov-Newtonian on a good night at 50X it is bright, large, pretty rich, somewhat compressed, 47 stars resolved, including Phi Cas. There is another bright star near Phi that gives the effect of having two glowing eyes looking back at the observer. In the Southwest we call this cluster the Kachina Doll, two sparkling eyes and the rest of the cluster outlines outstretched arms with feathers. The Zuni and Hopi tribes in the Southwest made such dolls for their rites. Raising the power with an 8.8mm provides a great view. The cluster is now about 60% of the field, a few more faint stars are seen, but overall a very nice view.
At a site far from the lights of Phoenix with a 13" Newtonain at 100X this cluster is bright, large, rich, compressed, 78 stars counted of mags 7 and fainter. It fills the central half of the field. At 150X the cluster is about 3/4 of the field and it appears that all the stars are resolved. There are still about 80 stars, but no fuzzy background. Phi Cas is sunshine yellow. In the drawing below, the Kachina Doll outline is almost upside down, the two bright “eyes” are on the SE side of the cluster.
NGC 457 13 inch 100X
M 52 Using pair of 10X50 Leupold binoculars for a site with a little light pollution, this cluster is bright, compressed, 3 stars resolved with a bright yellow star on the south side.
With a TV 102 refractor at a dark site it is bright, large, rich, compressed and very well detached from the Milky Way background. There are 28 stars resolved in a triangular shape. There is a very obvious fuzzy background glow. One star is much brighter than all the rest of the cluster, it is light yellow.
M 52 With a 13 inch Newtonian at 100X this cluster is bright, large, rich and considerably compressed, 96 stars counted in cluster. 8th mag star on West edge is light orange in color. Well detached from Winter Milky Way. 150X provides a great view, the cluster is about 60% of the field. In the central 4 arcmin there are 4 lovely, delicate pairs of mags 10....12 and a triple star of mags 10, 12 and 13. It appears that all the stars are resolved at this power.
M 52 13in 100X
NGC 7789 has been a favorite of mine since I first found it decades ago. It is a rich cluster and is easily seen in binoculars. Using a 6" f/6 Newtonian with a 22mm Panoptic eyepiece it is bright, large, not brighter in the middle, very compressed, rich. Stars sparkle on a huge, fuzzy background. Raising the power with a 8.8mm eyepiece shows 31 stars with direct vision another 20 very faint stars are seen with averted vision. Nice view in the RFT. Dark lanes cut through the cluster.
With the 13" f/5.6 Newtonian on an excellent night, I rated it Seeing=7 and Transparency=9. Obviously a cluster, even in the 11X80 finder. The finder only resolves 2 stars, the cluster is bright, large, and a little brighter in the middle. At 60X in the 13" it is bright, very large, rich and much compressed. There are 32 stars resolved and 2 dark lanes are obvious within the star cluster. Going to 100X with the 22mm Panoptic resolves 76 stars of magnitudes 10 and less. The cluster is about 1/3 of the field of view, with lots of beautiful chains of stars seen. I think that 150X with the 14mm Meade UWA is the best view, I estimated over 240 stars resolved by counting 63 stars resolved in the NE quadrant of the cluster. This grouping now takes up about half the field and the lovely curving chains of star are much more prominent. The dark lanes have excellent contrast at this power and are a unique addition to this beautiful cluster. Higher powers, 220X and 300X will bring out some faint double star within the cluster, but high magnification also looses some of the cluster aspect of this rich group of stars.
NGC 7789 6 inch 60X