A couple of sessions I didn't set down yet:
Last Saturday 4/16 I used the 12.5-inch for a solar session. Very large sunspot AR2529 was up, and I had nice views at 170x but with usual daytime mediocre (2 arc second) seeing. It's a EKI class sunspot, and appeared like the Trifid Nebula. One prominent filament arcing 2/3rds the way across the umbra, with shaggy extensions on the longer side of the arc. It reached out and touched a smaller filament arc which was orientated in an opposite way from the major filament. There was a third fainter arc reaching toward the base. Two more very faint filaments arced in opposite directions to the east of this central pair. The penumbra was irregularly shaped, and to the north there was a row of four smaller sunspots leading out of the umbra. A very complex view. When I saw photos of it later on they failed to capture the amount of detail I had seen -- perhaps the two secondary filaments were short lived. AR2532, a CAO group, was on the opposite (eastern) side, and a small group of three umbrae with thin penumbrae.
We had poor transparency and seeing between then and now, so I spent my evenings preparing a 10" f4.7 Dobstuff I acquired used. It is to be my "travel scope" to use on vacations and for outreach type of events. I glued the primary to a floating 6 point cell which I modified from the original. It's difficult to achieve balance with the 9x50 finder, so I will go without for now and have to rely on my Rigel finder skills. All my eyepieces come to focus, so will need a night out with it to see how it performs.
Thursday night 4/27 the sky was just good enough to get out and I viewed through the 12.5-inch. I planned to continue calibration of my astrometric eyepiece but seeing proved to be very bad. I had a look at 90 Leonis, a close but easily split pair at 170x, a yellow-white A and a bluish-white B. h4433 in Leo was a bright orange-yellow A with a much fainter blue B, widely separated, a beautiful sight. The main event was an Io occultation behind Jupiter. I saw Io pretty far out from Jupiter's limb at 9pm and went on to the doubles. I came back to it at 9:25pm when Io was a hair split from Jupiter's limb; I watched as it sank to meet the limb, then appear as a bright pimple. It disappeared at 9:30, exactly as the ephemeris predicted.
Friday night was to be a busy place on Jupiter, with two moon transits and other nice events, but it was too cloudy to set up -- marine layer blowing in.
Saturday, April 30, 2016
Saturday, April 16, 2016
comet chasing
There being a break in our cloudy weather I prepared for an observing session during my lunch hour yesterday. I wanted to give a try for 252P/Linear, which is now in Ophiuchus in the pre-dawn hours. While printing the finder chart at cometchasing/skyhound.com I saw the other possible targets and printed those out too. 116P/Wild is in Scorpius and ought to be visible. There were several evening comets and I convinced myself I could find those, even with the 1st quarter moon. Not.
I used the 12.5-inch for these sessions. I started out having a peek at Europa's shadow transit. Seeing was not very good, with intermittent decent views at 277x. The shadow was very small. What was nice was three of the moons made a straight line toward the shadow, in a kind of exponential stack: Ganymede at the far edge of the field, lined up with Io about three times further in, then Europa half way between Io and the planet, and finally the shadow on Jupiter's surface, all in a straight line. Calisto was way out of the field on the opposite side of Jupiter. (UT 4/16/16, 3:45 or so).
When it was finally dark I tried for the comets. C/2014 W2 (PANSTARRS) is in Draco, a fairly easy hop from Capella. There were a couple hazy patches in the field but nothing certain. It's 13.12 magnitude and 20.3 surface brightness -- and too close to the Oakland light dome. Nearby C/2013 US10 Catalina should have been easier but it too was not found. 333P/Linear was even lower on the horizon and fainter at 13.42. 9P/Tempel behind Leo's rump was too close to the moon, 13.52. 81P Wild, which looks like a fun target since it is booking through Gemini's left foot, was not seen. 104P/Kowal is another fast mover, through the Hyades, but too low and blocked by a tree.
So I occupied my evening looing at some double stars in Leo, 277x, with some nice surprises:
STT215: very close split (1.7" separation) near equal bright white stars
STT216: !! A white and bright (7.3), B red & much fainter (10.3), a close split (2"). Seeing needs to steady to see B
STF1448: An orange and blue pair. Fainter than Alberio but just as pretty.
STF1447: Both white, A (7.5) 2x brighter than B (8.9). Wide separation (4"). Is there a faint third? (no)
STF1487: Bright white pair (4.5, 6.3) wide sep (6")
STT105: very widely separated (11") orange pair. Pretty bright (7.3, 8.3).
S612: Very widely separated, split in finder (196"!); white A with a slightly red B
STT104: Very wide separation (208"!) orange pair.
Went to bed deciding to get up at 3:30am to have a try for the morning comets. Clara woke me up at 3:00am, somehow knowing my intentions. After she went back to sleep I went out. I first tried 116P/Wild, which should have been a cinch to find off of Delta Scorpii, but I could never match the star field on the finder chart which what I was seeing in my finder scope -- too many stars on the finder chart to make sense of. There's a straight trail of stars to the SW of delta which I found well enough, but I got lost from there. I swept around the area with and without my comet filter but no luck. It's mag. 12.91 & surface brightness 21.9, so maybe out of reach. Seeing was not that good (Pickering 6) and even though it was pre-dawn there was light dome from San Jose, and moisture blowing in from the ocean.
I moved on to Ophiuchus to find 252P/Linear, and finally met with success, but disappointment too. I found the comet but all I saw was a diffuse, irregular and rather large glow for a coma, brighter toward the center. I could not discern a nucleus. With the comet filter the glow became smaller but somehow more palpable. The comet was then 6.73, coma diameter 35.1', surface brightness 23.1. My SQML read 18.73.
After a look at the lovely large open cluster IC 4665, I moved on to the planets. Mars was a surprise, a large disk with Syrtis Major jutting down darkly from Hellas, which appeared as a large elliptical ice cap. It seemed the planet was tilted that I could see the whole of the circular cap. Utopia was a less dark on the northern end, bordering a northern ice cap along the rim. Nice view! I tried a couple of filters but didn't like the artificial view.
Saturn was next, just a sweep of the telescope away. Seeing was watery but there were some still seconds. Cassini division was distinct, as were the bands and polar and equatorial regions; it always reminds me of a rugby shirt pattern. What's exciting is I was able to see five of its moons! Titan was far out, and in line with it were Rhea and Dione on either side -- these were always visible. I caught and held Tethys with averted vision, and with time could have it direct vision. I then had hints of Enceladus with averted when the seeing stilled. It was an uncertain object but I added it to my sketch and I confirmed it this morning. Score!
By then the sky was brightening and the traffic noise from 880 was noticeably louder, so I packed up. I paused to look at the summer constellations just reaching meridian: Cygnus, Lyra, Sagittarius; things to look forward to. The I went in and had a nap on the couch.
I used the 12.5-inch for these sessions. I started out having a peek at Europa's shadow transit. Seeing was not very good, with intermittent decent views at 277x. The shadow was very small. What was nice was three of the moons made a straight line toward the shadow, in a kind of exponential stack: Ganymede at the far edge of the field, lined up with Io about three times further in, then Europa half way between Io and the planet, and finally the shadow on Jupiter's surface, all in a straight line. Calisto was way out of the field on the opposite side of Jupiter. (UT 4/16/16, 3:45 or so).
When it was finally dark I tried for the comets. C/2014 W2 (PANSTARRS) is in Draco, a fairly easy hop from Capella. There were a couple hazy patches in the field but nothing certain. It's 13.12 magnitude and 20.3 surface brightness -- and too close to the Oakland light dome. Nearby C/2013 US10 Catalina should have been easier but it too was not found. 333P/Linear was even lower on the horizon and fainter at 13.42. 9P/Tempel behind Leo's rump was too close to the moon, 13.52. 81P Wild, which looks like a fun target since it is booking through Gemini's left foot, was not seen. 104P/Kowal is another fast mover, through the Hyades, but too low and blocked by a tree.
So I occupied my evening looing at some double stars in Leo, 277x, with some nice surprises:
STT215: very close split (1.7" separation) near equal bright white stars
STT216: !! A white and bright (7.3), B red & much fainter (10.3), a close split (2"). Seeing needs to steady to see B
STF1448: An orange and blue pair. Fainter than Alberio but just as pretty.
STF1447: Both white, A (7.5) 2x brighter than B (8.9). Wide separation (4"). Is there a faint third? (no)
STF1487: Bright white pair (4.5, 6.3) wide sep (6")
STT105: very widely separated (11") orange pair. Pretty bright (7.3, 8.3).
S612: Very widely separated, split in finder (196"!); white A with a slightly red B
STT104: Very wide separation (208"!) orange pair.
Went to bed deciding to get up at 3:30am to have a try for the morning comets. Clara woke me up at 3:00am, somehow knowing my intentions. After she went back to sleep I went out. I first tried 116P/Wild, which should have been a cinch to find off of Delta Scorpii, but I could never match the star field on the finder chart which what I was seeing in my finder scope -- too many stars on the finder chart to make sense of. There's a straight trail of stars to the SW of delta which I found well enough, but I got lost from there. I swept around the area with and without my comet filter but no luck. It's mag. 12.91 & surface brightness 21.9, so maybe out of reach. Seeing was not that good (Pickering 6) and even though it was pre-dawn there was light dome from San Jose, and moisture blowing in from the ocean.
I moved on to Ophiuchus to find 252P/Linear, and finally met with success, but disappointment too. I found the comet but all I saw was a diffuse, irregular and rather large glow for a coma, brighter toward the center. I could not discern a nucleus. With the comet filter the glow became smaller but somehow more palpable. The comet was then 6.73, coma diameter 35.1', surface brightness 23.1. My SQML read 18.73.
After a look at the lovely large open cluster IC 4665, I moved on to the planets. Mars was a surprise, a large disk with Syrtis Major jutting down darkly from Hellas, which appeared as a large elliptical ice cap. It seemed the planet was tilted that I could see the whole of the circular cap. Utopia was a less dark on the northern end, bordering a northern ice cap along the rim. Nice view! I tried a couple of filters but didn't like the artificial view.
Saturn was next, just a sweep of the telescope away. Seeing was watery but there were some still seconds. Cassini division was distinct, as were the bands and polar and equatorial regions; it always reminds me of a rugby shirt pattern. What's exciting is I was able to see five of its moons! Titan was far out, and in line with it were Rhea and Dione on either side -- these were always visible. I caught and held Tethys with averted vision, and with time could have it direct vision. I then had hints of Enceladus with averted when the seeing stilled. It was an uncertain object but I added it to my sketch and I confirmed it this morning. Score!
By then the sky was brightening and the traffic noise from 880 was noticeably louder, so I packed up. I paused to look at the summer constellations just reaching meridian: Cygnus, Lyra, Sagittarius; things to look forward to. The I went in and had a nap on the couch.
Saturday, April 9, 2016
herschel II from a red zone
This past Monday and Tuesday nights I observed from my red zone backyard. SQML ranged from 18.3 - 18.5, which equates to Naked Eye Limiting Magnitude of 4.2 to 4.4. I was driven mainly to keep up with my Astronomical League H2 and Planetary Nebula lists. I have fallen behind on the lists due to cloudy weather this winter; the "next up" targets are all well past meridian. It has made me resent the lists somewhat -- why shouldn't I just observe whatever I want? But I do want to finish what I started, and I do want the validation which would come from completing the program. These lists are rather like college level classes, and if I complete the H2 I suppose I will have enough "credit" to have graduated.
In any case, the experience was a lesson in how light pollution affects the views. Surprisingly all but the most diffuse planetary nebula were viewable, as were the open clusters. Of course these would appear brighter, with more detail or more stars, in a darker sky; but they could be seen nonetheless. But the galaxies were hit hard. The galaxies on the H2 list have integrated magnitude of 13 or so, and in a dark sky are bright and obvious in the eyepiece, often yielding subtle detail. In my back yard they were threshold objects for which I needed to work hard to see. And this with a 20-inch telescope -- they would be quite out of reach of my 12-inch or 8-inch. In the coming months I could continue to observe from the back yard, but I should prepare myself for a frustrating experience.
Here are my notes:
NGC 2259, Open Cluster in Monoceros: @ 205x: Pretty arrangement of stars. Bright red star to the W. Bright white in middle with a few more fainter stars boxing it in. Three in SW make a triangle pointed NE. Faint stars come into view with AV, especially a close pair to SW of the center star. Stars mostly E-W. Did not see nebulosity. II1pn
NGC 2261, Reflection Nebula in Monoceros: @ 205x Hubble's Variable Nebula. Wow, interesting! Looks like a comet with a wide, faint but short tail, with a star as the comet nucleus. OIII loses it altogether, but UHC dims the point star but elongates the tail. I will come back to this over the years and try to note its changes. NGC 2264 the Christmas Tree Cluster is nearby, stopped for a look through the 50mm finder.
NGC 2274, Galaxy in Gemini: @ 205x: Very faint, threshold object. But I can see a small bright round core with a just stellar nucleus; halo is a faint round haze. There is a hint with AV of a second hazy core just to the north [this is NGC 2275], slightly elongated NNW-SSE, half the size of 2274
NGC 2331, OC in Gem: @ 121x: Coarse, large cluster, about 30 stars with medium range of brightness. A loose circlet of 5 stars to the east. "Y" shape overall, like the Hyades. A red star just SW of center. IV2m
NGC 2339, Gx in Gem: @ 121x. Very faint, AV only but can hold a brighter core with a suggestion of halo 3:2 N-S. Lies in a fine rich field of stars.
NGC 2415: Gx in Lynx: @ 121x: Faint oval glow, with a brighter center, in a line of three stars. A nice close double star is midway to the edge of the FOV to the north.
NGC 2493, Gx in Lyn: @ 121x: Seen DV but barely. AV brings out barely oval core with some mottling, and suggestion of round halo. Bright red star to the NE.
NGC 2500, Gx in Lyn: @ 121x: Excessively faint round haze, seen AV only. Diffuse -- no core noticeable. In a diamond shaped asterism.
NGC 2541, Gx in Lyn: @ 121x: Extremely faint streak, small. AV shows stellar nucleus, very diffuse halo 2:1 NNE-SSW
K2-2, Planetary Nebula in Mon: @ 205x: Faint bloated star suspected to be the PN. With OIII there was a small faint round shell with a central star -- the shell appeared best while blinking. It is at the base of a mini Big Dipper asterism
M1-7, PN in Gem: @ 205x: Can't believe I got this one in a red zone. Unfiltered appears as a bloated faint star. OIII shows it as a faint, small hazy ball with soft edges, slightly green. No CS.
NGC 2371, PN in Gem: @ 205x: Unfiltered appears as an irregular grey glow. With OIII two lobes appear--kissing orbs--both greenish. 2271 is to SW, the fainter 2272 is to NE. Stars appear in both lobes but they are not centrally placed; CS is supposed to be in geometric middle but was not seen.
NGC 2392, PN in Gem, @ 205x: Unfiltered can see CS with a round grey glow around it; a close-by star to the N. OIII loses the CS but shows the ragged outer fringe and mottling inside the shell, especially a bright inner shell rim on the NE side.
I made attempts at Abell 21 (aka Medusa Nebula) in Gemini on both nights, but I can't claim it. My sketch shows the correct star field, but I drew a small glow -- when I looked at images after the session I see it is a large, thick C shape. I suspected a large round but excessively faint glow, but it was so obscure I didn't pin it down as the nebula. Now that I know what to look for I will give it another try.
It's cloudy this new moon weekend, so very likely I will need to try the back yard again.
In any case, the experience was a lesson in how light pollution affects the views. Surprisingly all but the most diffuse planetary nebula were viewable, as were the open clusters. Of course these would appear brighter, with more detail or more stars, in a darker sky; but they could be seen nonetheless. But the galaxies were hit hard. The galaxies on the H2 list have integrated magnitude of 13 or so, and in a dark sky are bright and obvious in the eyepiece, often yielding subtle detail. In my back yard they were threshold objects for which I needed to work hard to see. And this with a 20-inch telescope -- they would be quite out of reach of my 12-inch or 8-inch. In the coming months I could continue to observe from the back yard, but I should prepare myself for a frustrating experience.
Here are my notes:
NGC 2259, Open Cluster in Monoceros: @ 205x: Pretty arrangement of stars. Bright red star to the W. Bright white in middle with a few more fainter stars boxing it in. Three in SW make a triangle pointed NE. Faint stars come into view with AV, especially a close pair to SW of the center star. Stars mostly E-W. Did not see nebulosity. II1pn
NGC 2261, Reflection Nebula in Monoceros: @ 205x Hubble's Variable Nebula. Wow, interesting! Looks like a comet with a wide, faint but short tail, with a star as the comet nucleus. OIII loses it altogether, but UHC dims the point star but elongates the tail. I will come back to this over the years and try to note its changes. NGC 2264 the Christmas Tree Cluster is nearby, stopped for a look through the 50mm finder.
NGC 2274, Galaxy in Gemini: @ 205x: Very faint, threshold object. But I can see a small bright round core with a just stellar nucleus; halo is a faint round haze. There is a hint with AV of a second hazy core just to the north [this is NGC 2275], slightly elongated NNW-SSE, half the size of 2274
NGC 2331, OC in Gem: @ 121x: Coarse, large cluster, about 30 stars with medium range of brightness. A loose circlet of 5 stars to the east. "Y" shape overall, like the Hyades. A red star just SW of center. IV2m
NGC 2339, Gx in Gem: @ 121x. Very faint, AV only but can hold a brighter core with a suggestion of halo 3:2 N-S. Lies in a fine rich field of stars.
NGC 2415: Gx in Lynx: @ 121x: Faint oval glow, with a brighter center, in a line of three stars. A nice close double star is midway to the edge of the FOV to the north.
NGC 2493, Gx in Lyn: @ 121x: Seen DV but barely. AV brings out barely oval core with some mottling, and suggestion of round halo. Bright red star to the NE.
NGC 2500, Gx in Lyn: @ 121x: Excessively faint round haze, seen AV only. Diffuse -- no core noticeable. In a diamond shaped asterism.
NGC 2541, Gx in Lyn: @ 121x: Extremely faint streak, small. AV shows stellar nucleus, very diffuse halo 2:1 NNE-SSW
K2-2, Planetary Nebula in Mon: @ 205x: Faint bloated star suspected to be the PN. With OIII there was a small faint round shell with a central star -- the shell appeared best while blinking. It is at the base of a mini Big Dipper asterism
M1-7, PN in Gem: @ 205x: Can't believe I got this one in a red zone. Unfiltered appears as a bloated faint star. OIII shows it as a faint, small hazy ball with soft edges, slightly green. No CS.
NGC 2371, PN in Gem: @ 205x: Unfiltered appears as an irregular grey glow. With OIII two lobes appear--kissing orbs--both greenish. 2271 is to SW, the fainter 2272 is to NE. Stars appear in both lobes but they are not centrally placed; CS is supposed to be in geometric middle but was not seen.
NGC 2392, PN in Gem, @ 205x: Unfiltered can see CS with a round grey glow around it; a close-by star to the N. OIII loses the CS but shows the ragged outer fringe and mottling inside the shell, especially a bright inner shell rim on the NE side.
I made attempts at Abell 21 (aka Medusa Nebula) in Gemini on both nights, but I can't claim it. My sketch shows the correct star field, but I drew a small glow -- when I looked at images after the session I see it is a large, thick C shape. I suspected a large round but excessively faint glow, but it was so obscure I didn't pin it down as the nebula. Now that I know what to look for I will give it another try.
It's cloudy this new moon weekend, so very likely I will need to try the back yard again.
Monday, April 4, 2016
willow springs
Saturday night my friend Balint and I went to Bob Ayer's property in San Benito County, called Willow Springs 3000 (which is its elevation). I borrowed another friend's SUV in order to make it up the 3 mile unimproved dirt road to the site. It's a good thing, as this year's El Nino left a number of 8-12 inch deep runoff gullies in the road. The grass and weeds were vigorous, taller than the hood of the SUV. I missed one turnoff because it was hidden behind a wall of grass. Bob doesn't have any cattle on the property, so it is untouched California wilderness. It was a fun, if crazy, drive.
My allergies reacted to all the grass, and I had forgotten to take anything before going out. I'm still feeling the effect two days later. Because my eyelids were swollen, I had trouble reading my atlas, and had to turn my red flashlight brighter than I wanted to. I had trouble with collimation, and finding objects was difficult -- the greater number of stars which are visible and the finer scale of the atlas take some getting used to. Adding to these frustrations, the sky quality was poor, with thick water vapor in the air (Jupiter had a halo all night) and bands of cloud moving through. We knew transparency wouldn't be good but went anyway, since relatively clear dark nights are few this time of year.
Balint had a good night, catching a couple dozen Messier objects, and even finding Omega Centauri around midnight. I tried a couple MASH planetaries but did not see them, either because they are just beyond my scope in these conditions, or just beyond my scope, period. These are all setting soon after dark now; I probably won't get another chance at them until next year. I continued finding AL H2 and PN list objects, all of which were setting really fast -- I am behind the time on those lists. All of this sucked the enjoyment out of the experience. I decided we should pack up at 1am and head home. After dropping Balint off I arrived back at 4:30am and slept on the couch.
As I review my notes I find I had a modestly good night, all things considered. However I do need to get out, if even in the backyard, to continue working the lists -- just to take some of the pressure off myself. Virgo is coming up and there are more than one night's session there. I was also hoping to do another Herschel Sprint. We'll see if the marine layer can hold off the Bay Area for a few days to let me catch up. I'm thinking once these are done I will avoid long list projects for a while, and just plan my sessions around interesting targets which happen to be in favorable positions once I do have a chance to observe.
Here are my notes; all in the 20-inch, poor transparency but good seeing:
NGC 2139, Gx in Lepus: Fairly bright longish glow, gradually brighter in middle, N-S position angle. Some brightening in halo to the N. Seems to be longer than field guide suggests; W and E halo must be dimmer. Two foreground stars at NE tip; triangle of stars to NW in field.
NGC 2170, Reflection Nebula in Mon: Fairly bright round glow of nebulosity surrounding a 8th magnitude star. UHC gave more contrast. Fainter star to ENE also showing some nebulosity
NGC 2182, RN in Mon: Faint, small round nebulosity around star. Direct vision object but better with averted; UHC provides contrast. Middle in line of 3 stars running W-E.
NGC 2196, Gx in Lep: Bright oval core and diffuse halo with hint of spiral (some darkenings / brighter streaks in halo). An almost bar-like brightening in the core NW-SE. Halo and core are themselves 2:1 NE-SW. Bright and fairly large.
NGC 2236, open cluster in Mon: Comma shaped group of ~40 stars. Bright star in center of round group. Extension is of fainter stars and starts on west side of main group and loops south. II2m. Rich field. Interesting object.
NGC 2245, RN in Monoceros: Sparse scattered group of field stars; nebulosity is fairly bright, large, irregular shape tending SW-NE. Bright star on ENE edge of nebulosity. UHC helped contrast to see nebula better
NGC 2252, OC in Monoceros: Extent of OC fills FOV. Makes a shallow "Y" shape with double rows of stars forming the cross beam. A string of stars going N-S hooks to the SW at it's tip. With OIII shows faint nebulosity in the N-S chain, probably fringes of the nearby Rosette Nebula. Rich field but separated; III2mn
NGC 2254, OC in Monoceros: Faint, sparse but tight group; seems mostly unresolved. Arc of 6 stars open to east runs through the middle of the cluster. I1m
NGC 2269, OC in Mon: Vaguely "L" shape of brighter members with unresolved stars in patches around them. II1p. Taller part of L pointed N.
NGC 2302, OC in Mon: Faint circlet of stars with concentration / appendage to the east. An arc of three bright stars to the west cups the cluster. III2m
NGC 2309, OC in Mon: Faint and small group, a dozen brighter stars with a sprinkle of stars behind. Triangular shape pointed north. Bright field star to NNE. I2m
NGC 2316: Emission & Reflection nebula in Mon: Small faint glow just to north of a small, tight cluster of stars (which has a single bright star in its middle). Nebula is brightest in the middle and is mostly round, with short faint wisps extending to the south.
NGC 2346: Planetary Nebula in Mon: Visible unfiltered as a star with irregular haze around it. OIII loses the CS but shows a distinct apple-core (bipolar) shape orientated NNW-SSE, and a bright central core. No connecting rims to E or W sides.
NGC 2467: EN in Puppis: Extensive greenish nebulosity in a very rich field. Surrounds a bright star with many wisps to the S & SE. "V" of ~14 stars pointing from W to E is Haffner 18. OIII helps provide more contrast; panning the scope shows much of the area fogged with nebulosity
Jonckheere 900: PN in Gemini: Unfiltered appears as a small unfocussed star. With OIII is a round, evenly bright sphere, slightly green. No CS. Nice!
NGC 2452, PN in Pup: Very rich field. PN visible unfiltered as a bloated faint star, but needs OIII to see better. Small, overall round but brighter rims on N and S make it look hourglass. No CS; slightly green color. OC NGC 2453 is 6' to N in FOV, very pretty. OIII wipes out most of the stars in the field.
My allergies reacted to all the grass, and I had forgotten to take anything before going out. I'm still feeling the effect two days later. Because my eyelids were swollen, I had trouble reading my atlas, and had to turn my red flashlight brighter than I wanted to. I had trouble with collimation, and finding objects was difficult -- the greater number of stars which are visible and the finer scale of the atlas take some getting used to. Adding to these frustrations, the sky quality was poor, with thick water vapor in the air (Jupiter had a halo all night) and bands of cloud moving through. We knew transparency wouldn't be good but went anyway, since relatively clear dark nights are few this time of year.
Balint had a good night, catching a couple dozen Messier objects, and even finding Omega Centauri around midnight. I tried a couple MASH planetaries but did not see them, either because they are just beyond my scope in these conditions, or just beyond my scope, period. These are all setting soon after dark now; I probably won't get another chance at them until next year. I continued finding AL H2 and PN list objects, all of which were setting really fast -- I am behind the time on those lists. All of this sucked the enjoyment out of the experience. I decided we should pack up at 1am and head home. After dropping Balint off I arrived back at 4:30am and slept on the couch.
As I review my notes I find I had a modestly good night, all things considered. However I do need to get out, if even in the backyard, to continue working the lists -- just to take some of the pressure off myself. Virgo is coming up and there are more than one night's session there. I was also hoping to do another Herschel Sprint. We'll see if the marine layer can hold off the Bay Area for a few days to let me catch up. I'm thinking once these are done I will avoid long list projects for a while, and just plan my sessions around interesting targets which happen to be in favorable positions once I do have a chance to observe.
Here are my notes; all in the 20-inch, poor transparency but good seeing:
NGC 2139, Gx in Lepus: Fairly bright longish glow, gradually brighter in middle, N-S position angle. Some brightening in halo to the N. Seems to be longer than field guide suggests; W and E halo must be dimmer. Two foreground stars at NE tip; triangle of stars to NW in field.
NGC 2170, Reflection Nebula in Mon: Fairly bright round glow of nebulosity surrounding a 8th magnitude star. UHC gave more contrast. Fainter star to ENE also showing some nebulosity
NGC 2182, RN in Mon: Faint, small round nebulosity around star. Direct vision object but better with averted; UHC provides contrast. Middle in line of 3 stars running W-E.
NGC 2196, Gx in Lep: Bright oval core and diffuse halo with hint of spiral (some darkenings / brighter streaks in halo). An almost bar-like brightening in the core NW-SE. Halo and core are themselves 2:1 NE-SW. Bright and fairly large.
NGC 2236, open cluster in Mon: Comma shaped group of ~40 stars. Bright star in center of round group. Extension is of fainter stars and starts on west side of main group and loops south. II2m. Rich field. Interesting object.
NGC 2245, RN in Monoceros: Sparse scattered group of field stars; nebulosity is fairly bright, large, irregular shape tending SW-NE. Bright star on ENE edge of nebulosity. UHC helped contrast to see nebula better
NGC 2252, OC in Monoceros: Extent of OC fills FOV. Makes a shallow "Y" shape with double rows of stars forming the cross beam. A string of stars going N-S hooks to the SW at it's tip. With OIII shows faint nebulosity in the N-S chain, probably fringes of the nearby Rosette Nebula. Rich field but separated; III2mn
NGC 2254, OC in Monoceros: Faint, sparse but tight group; seems mostly unresolved. Arc of 6 stars open to east runs through the middle of the cluster. I1m
NGC 2269, OC in Mon: Vaguely "L" shape of brighter members with unresolved stars in patches around them. II1p. Taller part of L pointed N.
NGC 2302, OC in Mon: Faint circlet of stars with concentration / appendage to the east. An arc of three bright stars to the west cups the cluster. III2m
NGC 2309, OC in Mon: Faint and small group, a dozen brighter stars with a sprinkle of stars behind. Triangular shape pointed north. Bright field star to NNE. I2m
NGC 2316: Emission & Reflection nebula in Mon: Small faint glow just to north of a small, tight cluster of stars (which has a single bright star in its middle). Nebula is brightest in the middle and is mostly round, with short faint wisps extending to the south.
NGC 2346: Planetary Nebula in Mon: Visible unfiltered as a star with irregular haze around it. OIII loses the CS but shows a distinct apple-core (bipolar) shape orientated NNW-SSE, and a bright central core. No connecting rims to E or W sides.
NGC 2467: EN in Puppis: Extensive greenish nebulosity in a very rich field. Surrounds a bright star with many wisps to the S & SE. "V" of ~14 stars pointing from W to E is Haffner 18. OIII helps provide more contrast; panning the scope shows much of the area fogged with nebulosity
Jonckheere 900: PN in Gemini: Unfiltered appears as a small unfocussed star. With OIII is a round, evenly bright sphere, slightly green. No CS. Nice!
NGC 2452, PN in Pup: Very rich field. PN visible unfiltered as a bloated faint star, but needs OIII to see better. Small, overall round but brighter rims on N and S make it look hourglass. No CS; slightly green color. OC NGC 2453 is 6' to N in FOV, very pretty. OIII wipes out most of the stars in the field.
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