Had a nice opportunity to go out observing this new moon cycle to Fremont Peak Thursday night. The 2600' elevation was above the inversion layer which has been holding cold air, and poor seeing and haze, in the Bay Area. It was indeed warm and dry all night, not a trace of dew. Seeing was ok but not great. I set-up on the pads next to Peter N. and Dave C., both of whom I haven't seen since a CalStar a couple years ago. Peter had a 16-inch dob and I suggested we try Mira later in the night, but when Peter tried, he knew seeing would not be up for such a difficult observation. SQML was 20.5 according to Dave, not great but OK for me.
I brought my 10-inch f/3.7 Swayze and night vision. I didn't have a particular plan, other than to observe various large objects with this scope, which I don't recall having out in the winter. I searched around in Interstallarium searching for nebula. I observed exclusively with the PVS-14 afocally with the 67mm plossl, with a 2.5ยบ TFOV.
NGC 1491: Sh2-206, aka "The Fossil Footprint Nebula," is an emission type bright nebula located about 9,800 light years away in Perseus. It is an older, evolved HII region ionized by the O5 star BD +50 886. It was discovered by William Herschel. With 3nm Ha there was a very bright central milky knot mottled heavily with dusty-looking haze, and a sharp cut-off on the west side. The mottled nebulosity rippled away from this central area and diffused to the east, and with some bright semi-arc streaks mixed in with fainter dusty haze. Later in the night I observed this region with the NV device handheld with an Ha filter, and this nebula seemed to form the apex of a long stream of very faint nebulosity running south parallel to Perseus, forming a sort of cape.
vdB 14 & 15: Part of the van den Bergh catalog of bright reflection nebulae, located in Camelopardalis, and circumpolar. They are faint bluish reflection nebula created as starlight from nearby bright stars scatters off interstellar dust. Nicknamed "The Space Waterfall" by astrophotographers. vdB 14 is a faint, dusty looking mottled elongated glow, with some sinuous seams flowing its length, its illuminating star off to one side, like a mini California Nebula. vdB 15 was an irregularly round glow around a bright star, with diffuse edges.
NGC 1333: Embryo Nebula. In my notes I wrote "this looks like a beetle." The "head" is mostly round with edges nibbled with dark nebula, with two pillar like formations. There is a prominent dark intrusion which helps separate the head from the rest of the body. The body has bright rims or ridges of brighter sections which are denser areas facing stellar winds. It is bisected lengthwise (the "suture") with darker mottling, and there are also crusted with dark nebula. According to the internet, the nebula is primarily composed of molecular hydrogen, dust, and ionized gases. Ultraviolet radiation emitted by nearby young, massive stars causes surrounding gas to glow and forms intricate filaments, knots, and cavities in the nebula.
NGC 663: The "Letter 5" nebula, which can be seen as an asterism of some of the brighter stars in the large, fairly loose, and rich cluster. There is a central round region of fainter stars, with arc of moderately brighter surrounding it.
NGC 1624 = Sh2-212: Small sparse open cluster surrounded by a bright but hazy, dusty glow. Brighter to the middle and diffuse edges, mottled and streaked with dark nebula, looks to me like a lion's mane.
PN IPHASX J055226.2+323724 in the open cluster M37. Discovered in 2022, the PN in M37 is the third known planetary nebula associated with an open cluster, and it has been determined to have a kinematic age of 70,000 years. This age is based on the nebula's expansion rate, which is consistent with the properties of the host star. I first tried to observe it a couple of years ago in Mark Wagner's 18-inch telescope with night vision but could not convince myself I saw it then. This time, after a few minutes observing, I noticed a very faint oval glow in the correct area of the nebule (northern edge). In my field sketch I roughly drew the cluster and in particular three brighter stars on the periphery which were just to the side of the faint glow I saw, which I drew and pointed and wrote "here?" for me to follow up later. Now that I have the discovery image below, I can confirm I did indeed see the nebula, nearly to its fullest extent (minus the very faint wisps trailing away from the cluster).
B33 Horsehead Nebula: Everyone with NV will look at the Horsehead, since such a difficult object is so easily seen with the device. I observed it with 1x, just holding the device without a telescope, as a dark intrusion into the nebula. At 3x, with a lens attached to the front of the device, I can see the direction of the snout. With the 10-inch scope, I saw the bump on the horse's head, the protrusion of the snout, the rim of bright nebula running along the top of the head, and even the trail of dark nebula which would be the mane of the neck, but it's separated by a very thin strip of brighter nebula. IC 434, the bright nebula, forms a bright, sinuous line not unlike some portions of the Veil Nebula (i.e. the Witch's Broom), and huge sheets of the bright nebula seem to evaporate off this line into the sky.
Sh2-261: Lower's Nebula. According to the internet, H. A. Lower discovered this nebula in 1939 by using an 8-inch f/1 Schmidt camera with Agfa Superpan Press film and exposure time of 20 minutes. An emission nebula with both Hb and OIII emissions, it showed up well in my Tri-band filter (Ha, Hb, OIII). The dark central region is lined with irregular streaks and patches of nebulosity, brighter on the southern side. The southern side is smaller than the northern, which is turbulent and diffuses slowly in a great arc which trails to the east. The western edge has a very faint pointed stream of nebulosity which looks like a break-out from a planetary nebula. A great amount of detail in this large nebula which nearly filled the field of view.
Abell 12: Appeared as a tiny thick, smooth-edged ringed planetary with a soft milky middle next to bright star Mu Orionis. Did not have enough magnification to notice the breakout along the northern edge.
M1: Best seen through the dual band filter (Ha+OIII). Hairy oval shape, heavily mottled, with two round bright loops in nearly complete intersecting circles. I'd love to view this with a larger scope with more image scale.
Abell 21 Medusa Nebula: Bright dome shape with a fairly crisp upper edge and two trailing "legs" on either side. The center is filled with milky nebula, and the very faint breakout nebula can be seen flowing away opposite from the dome.
NGC 2261 Hubble's Variable Nebula looked like a small squat comet with a broad fan-shaped tail. One edge of the tail was like a bright small spike, and the other was a bright, longer streak which curved back behind the nebula. In between these sides was filled with subtle greyscale changes of bright nebula, suggesting structure even in the tail. Wish I could have used more magnification.
Sh2-310: Large wash of nebula floating near open cluster NGC 2362. According to Wikipedia t is one of the largest H II regions known in the Milky Way and us ionized by the stars Tau Canis Majoris and UW Canis Majoris. What I was looking at in the scope was the brightest patch of this giant cloud. Its entire extent is best seen with the NV device handheld at 1x, where it forms a kind of tail to Canis Major. I also noticed faint streams of nebula which linked it to the Seagull Nebula -- of which most are familiar with the brightest part forming the Seagull shape, but don't see the bubble the wings form unless using low power NV. Here is the Finkbeiner image from Aladin to illustrate.
Planetary Nebula FR 2-25. For a full description and a wonderful image of this object, go to Jon Talbot's Astrobin page here. I noticed this on my atlas and gave it a try, using my Nexus DSC with the Ra & Dec entered to find the general area. After at least 10 minutes of careful observation, I noticed an extremely faint small glow arcing away from a string of four faint stars (an arc of brighter stars was to the SE). My notes are "vague cloudiness here in the right spot" with a sketch of the curve and the star field. A pretty difficult observation but worth the effort!
NGC 2403: According to Wikipedia, this is an intermediate spiral galaxy in the constellation Camelopardalis. It is an outlying member of the M81 Group and is approximately 8 million light-years distant. In the scope it was small and fairly bright, with a bright quasi-stellar nucleus, and a heavily mottled 3:1 halo, with two arms visible on each side looping inside the halo.
NGC 4236: Appeared very faint, at the edge of perception, unfiltered as a small cloudy elongated contrast change. NV is not always good for galaxies. Per Wikipedia, it is a barred Magellanic spiral galaxy located in the constellation Draco. The galaxy is a member of the M81 Group, a group of galaxies located at a distance of approximately 11.7 Mly (3.6 Mpc) from Earth.
As Peter and Dave packed up at around 12:30am, Peter pointed out he could see Kemble's Cascade naked eye and gave us the instructions to look. It was at zenith, and one started from Perseus' "head" and looked east several degrees for a line of stars. Really nice to see it this way.
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