night of two comets

I had the itch to go to a dark site this new moon, and this past Sunday presented an opportunity.  I went up to Fremont Peak, feeling the higher elevation would make up for the very slight 0.2 MPAS difference in sky darkness from my usual site.  I had the place to myself; I don't think there were even any campers.  There were low clouds along the southern horizon, so I kept to higher targets.  Seeing was very good.

I struggled as to which scope to bring.  I decided on the Ayers 4-/8-inch combo refractor, since it has been many months since I brought it out, and I had cleaned and collimated it a couple weeks ago.  It performed nicely, which I noticed right away when aligning my Telrad on the communications tower's warning lamps -- I could clearly see every detail.  

There were two comets up in the sky, which I observed as soon as it was dark enough.  

The first was C/2025 A6 Lemmon, a bright magnitude 2.78 with a 13.3' diameter coma and only 0.6 AU.  It was a few degrees SW of Rho Boötes, and I swept it up in my 8x42 birding binoculars before panning to it with the 4-inch visually, then conveniently switched to the 8-inch visually by flipping the folding mirror up.  Lemmon had a small, very intensely bright coma immediately around the nucleus, and the coma was rounded some distance in front (with a bright bow-shock arc).  The dust tail was bifurcated and rather stumpy, distinctly mottled inside.  I also looked at it with 3x night vision, and it was very striking in the field with a fat, stumpy tail, with a star in the center of the tail.  In the 8-inch with night vision, the tail was much lengthened and with two bright streaks in addition to the mottling.  I could detect subtle movement in the comet from when I had observed it 20 minutes prior visually.  This image is brighter and more detailed than what I saw, but conveys the impression:

The second comet was C/2025 R2 SWAN.  This was fainter, magnitude 7.00, with a 10.3' diameter coma with only a 0.3 AU distance.  It was more difficult to find since it had slipped east of the main Milky Way in Scutum.  I eventually swept it with my binoculars as a largish hazy glow, and then needed to sweep in the area with the 4-inch with night vision to find it.  It was smaller, with a fairly bright coma and a stumpy thick tail.  It's too bad I wasn't out a couple nights ago when this comet flew past M16.

I proceeded to observe with night vision in place.  I observed a few items from Steve's Deep Map 600 before realizing it is more suited to a telescope with greater image scale.  The 4-/8- combo is best suited to larger fields.  So, I searched my atlas for larger nebula.  I won't relate every observation, many of which I've seen before.  Just a few were more interesting:

Sh2-176: 00 31 38.3 +57 17 09, 10' diameter.  Planetary nebula. 

Very faint, round, mottled, with broken sides.  8-inch Ha.  

Sh2-170:  00 01 42.0 +64 37 24, 20' diameter

Irregularly round, mottled inside, it's the gas cloud around the unremarkable open cluster Stock 18.

NGC 6946: Fireworks Galaxy, a face-on spiral appeared small, faint, overall oval with a small bright nucleus and hints of spiral mottling inside.  Near open cluster NGC 6939, bright, dense, fan shaped.  Both in a dense field.

NGC 7380 / Sh2-142 "Wizard Nebula" but I described it as "fish-head shaped" diffuse nebula with a small dark pillar, associated with rich open cluster NGC 7380.   8-inch Ha

IC 342: face on spiral, best seen unfiltered with gain set to low, very faint halo was a contrast change with the background sky which nevertheless intimated spiral form, with a moderately brighter central mottled cloudiness with stars like a small open cluster. 

NGC 1499 California nebula.  Appeared positively solid, like part of a thundercloud, with darker and lighter streams and puffs, the central part is thick and heavily mottled with dark blotches.  4- and 8- inch, Ha.

NGC 752, a favorite open cluster, which I vividly remember observing for the first time from CalStar in 2015? with my old 12.5-inch f/7 dob, remembering the richness of the stars with the bright nearby red stars, and fainter red stars in the cluster.  Large and loose, with a good range of star brightness, it seemed less dense than I remembered (difference in aperture), but still wonderful.  8-inch, visually.

Toward the end of the night, I observed with night vision 1x with Ha, and what struck me was the cape of faint nebulosity off Perseus' shoulder, Mel 20 and east.  There are some small brighter knots to it (NGC 1491 is one), but it is really an unnoticed flow of nebula.  I can't find a good image of it, even in Finkbeiner's survey.   Worth further exploration.

Woke at 5am to try to beat traffic and be home to drive the kids to school (there was still some traffic in Morgan Hill).  I drove down to the bathroom building having left my eyepiece and clothes bag on the roof of my car!  Luckily I noticed before driving down the hill.

7 october 2025

Nice night with the 6-inch, good transparency and seeing.  I continued through the red star list, which I'm enjoying quite a lot:

19 Psc: yellow-orange 

47 Cap: pretty light orange  

7 Cet: bright light yellow 

77 Peg: yellow 

AC    1 AB: Rusty yellow A and much fainter B emerges beyond first diffraction, with seeing.  SOC grade 4 orbit, 525-year period, currently at periastron.

00h 20m 54.10s +32° 58' 40.9" P.A. 289.00 sep 1.9 mag 7.27,8.26 Sp F5V dist. 67.93 pc (221.59 l.y.)

AGC  14 AB: Light yellow.  With 380x and seeing, 3 Dm B split on A's first diffraction ring.  SOC grade 4 orbit, 635-year period, it is at apastron and may show movement from PA north to east in the next 20 years.

23h 43m 59.48s +29° 21' 41.2" P.A. 284.00 sep 0.8 mag 5.07,8.10 Sp G8III dist. 68.78 pc (224.36 l.y.)

BU  181 AB: red-orange A and very much fainter bluish B, barely split, with 380x

18h 18m 07.72s +23° 17' 49.0" P.A. 222.00 sep 37.5 mag 6.68,11.50 Sp K5 dist. 497.51 pc (1622.88 l.y.)

BZ Psc  very light yellow

DK Psc faint, very slightly red 

EP Aqr  deep red-orange

H N 140 AB light orange with wide faint companion 

HD 210926 red-orange 

HD 215851 faint, very slightly reddish 

HD 220123 light yellow 

HD 221273 very light yellow 

HD 221832 light yellow 

HD 223771 faint very light yellow

HR 237 light orange 

HR 9055 light yellow-orange 

Phi Peg light yellow 

PQ Peg faintly dried blood color red

R  Aqr slightly red 

6 october 2025

Observed with the 20-inch for only a little while before I had an azimuth encoder error and had to end the session.  I'll need to tear down the scope to get at it (I hope it's as simple as a loose set screw).  That's probably a good thing as I can clean the structure and give it some maintenance.

Seeing and transparency were ok, with a nearly full moon.  I observed from the red star list, all of these at 140x:

BLL  41: gorgeous deep orange in a very rich field. 

BLL  42: deep orange 

BLL  43: striking, bright deep orange. 

HD 227112 yellow-orange, close to a bright light-yellow star

V2093 Cyg bright yellow-orange in a rich field 

WEB   9: striking group: orange and blue unequal wide pair, like Albeiro, with a third fainter pale blue star in an arc, and a wider, brighter blue-white star below the arc.  The primary star is a 0.4" unequal pair, did not try for it.

 

26 september 2025

A nice night with the 6-inch, though transparency was off -- as were my DSC.  Somehow it was giving me grossly incorrect push to directions.  I needed to re-align a couple of times during the night.

The best view was at the end of the session, around 10:30pm, when I used my Bino viewer on Saturn.  I'm not convinced it was due to the binocular summation factor, but I did see all five of Saturn's brightest moons, even though three of them were quite close to the rings.  Tethys and Enceladus were so close together they looked like a double star, and Rhea was hanging from the tip of the ring.  The moons were very small, very faint, and flashed to view with more time observing.  The rings are still nearly edge-on, and the banding on the disk was subtle -- though both poles appears somewhat flattened.

  

I continued observing the red star list:

AQ And light orange-red, low power shows the color best 

BLL   2A very subtly orange, brief impression of color when first look but it becomes bland with more observation

BUP   1A faint deep orange, richer color with lower power 

H 4  66A faintly orange wide faint B 

HD 232372 faintly reddish 

HD 7734 off white or slightly yellow 

HD 8701 golden, very pretty

HR 237 light orange

V466 Cas, bright light yellow, with a slightly fainter wide companion nearby.  These are the "eyes" of the Owl Cluster NGC 457, which was in the field -- though did not make a strong Owl-shaped impression, likely because many fainter members were not visible due to light pollution.

Z  Psc nice medium orange 

21 september 2025

Spent the night with the 20-inch, with average transparency and seeing.  I cleaned the mirror beforehand as it has been many weeks since I've used the scope.  I observed a couple doubles but I've tapped out the CDSA list, and the seeing wasn't good enough to observe movement pairs.  I was left to observe stars off the red color star list.  A nice night all the same.

STF2367 AB: 508; 560x: Light orange stars, suspected double with lower power, good clean split with 560x, 1 Dm, PA to the NE, with wide AB-C to the south.  No Gaia parallax data for A.  SOC grade 2 orbit, 92.2-year period, it is approaching periastron and will hang near its current position for the next 20 years.

18h 41m 16.36s +30° 17' 40.9" P.A. 71.00 sep 0.4 mag 7.70,8.03 Sp G3IV dist. 136.05 pc (443.8 l.y.)

STF2431 A 178; 140x: Wide 3 Dm.  This was on the red star list.  The primary is not particularly red, the faint companion is slightly so. 30% PRO, 6,475 AU WS, 4.3+1.9 Msol, 0.08 PMV, it is possibly binary and an orbit can be tried.

18h 58m 46.59s +40° 40' 45.1" P.A. 236.00 sep 19.0 mag 6.17,9.61 Sp B3V dist. 300.3 pc (979.58 l.y.)

STTA171 AB: 178; 140x: Light yellow A and wide unequal B.

18h 32m 51.48s +38° 49' 59.8" P.A. 328.00 sep 150.1 mag 7.02,8.12 Sp F8+G5

36 Aql: Bright light yellow 

BLL  35A light yellow 

HD 171912 very light yellow 

HD 173130 off white 

HD 173632 very light yellow-orange

HD 174883 faint light yellow 

HD 176132 light yellow 

HD 182566 similar fainter off white 

HDS2700A off white 

HDS2704A nice rich orange 

HDS2759A off white 

HK Aql lgitht orange 

HK Lyr very like T Lyr, intense light orange 

HR 7148 ligtht yellow 

HR 7208 light yellow 

PPM 167106 another faint dried blood color star 

T  Lyr faint, so more intense light orange 

UW Aql faint dried blood/rouge color 

XY Lyr  very light orange 

not just for nebula anymore

The star party I planned to attend later this week is being disrupted by the remnants of a tropical storm, with risks of showers and thunderstorms.  Tuesday night (the 16th) seemed the only night I could get away for a darker sky, but being a weekday meant fighting traffic in all directions.  I ended up going to Henry Coe as it's relatively close.

I have been working to recover the 8-inch folded refractor I bought almost a year ago and have made some progress (correcting a flipped objective, adjusting the flat mirror height to spec.) but it still does not provide good clean images.  So instead of bringing it out, I brought my C8, intending to use it in prime focus mode to view star clusters and galaxies.  With prime focus in the C8 I have 78x magnification and 0.5-degree field of view (I couldn't reach focus with my corrector, I need to try a different diagonal).  Unfiltered the whole night.  It fit the night pretty well, and I had been meaning to try out this combination for several months anyway.  Since the Milky Way is slipping into the western sky, and the west is completely washed out at Henry Coe by light pollution, it was no night to try nebula.  The C8 was the best choice, and I'm glad I got to know its capabilities with night vision.

I was the first in the lot and Richard and Philip arrived at sunset.  Richard with a 5-inch refractor and Philip with a lovely 17.5-inch dob.  Once dark I ran through alignment on the AVX mount with Mirach as the last calibration star, and I immediately noticed NGC 404, Mirach's ghost, pretty bright oval with a bright central core.  It is an isolated dwarf lenticular galaxy around 10 mly distant, just outside our local group.  Off to a good start.

I ran through a number of open clusters to start, such as M52, NGC 129, and so on.  NGC 7789, Caroline's Rose, was especially beautiful and really does look like a rose, with semi-circular loops of bright and faint stars expanding from the center and folding into each other.  SQML was 20.4 once fully dark.

I then went through mostly galaxies, and I was very impressed with what I could see.  I had the sense I was seeing in the C8+NV what I had seen with my 20-inch from much darker skies.  

NGC 7331: Bright round core, like a ball floating on a frisbee, an effect of the contrast between the very elongated halo and subtle dark lanes on the near-side close to the core.  Flea NGC 7340 noticed immediately, well away from the galaxy, with NGC 7335 seen with slightly more effort, and smaller, fainter NGC 7336 noticed with considerably more effort.  NGC 7336 not noticed at all, nor the supernova, nor the very tiny NGC 7326 or NGC 7325 on the other side of the galaxy than the fleas.  Philip tried with his 17.5-inch, and I could pick out NGC 7340 pretty well, but not any others -- I may not have been dark adapted because of the night vision device.  Richard was able to see the three I mentioned.

Stephen's Quintet: 3 galaxies (NGC 7318, 7319, 7320) seen with certainty as in a triangle, with a sense of the area inside and around the triangle lumpenly brighter from the surrounding skies.  7318 was the brightest, elongated with a bright core, the other two were small soft irregular glows.

NGC 7549, NGC 7550, NGC 7547: Three galaxies forming an isosceles triangle.  7459 was a small non-stellar oval glow, oriented N-S next to a bright star.  7550 was fairly evenly bright, larger round glow.  7547 was small, elongated 3:1 ENE-WSW, with a bright stellar core.  

NGC 40's bright irregularly round shell had brighter edges on either side of the outer shell, like parenthesis.  There was a gap between the bright central star and the shell, and outflows of nebula escaping the poles.  Most curiously, these outburst portions positively shimmered -- not from seeing, but as if by variations in light pulses.  I observed this twice at different times during the night, at different elevations, and the effect was the same.  

NGC 1501: Prominent central star, faint round halo with crisp edges, forms a subtly irregularly round circle, with soft mottling inside the halo.

NGC 382 is in the center of a 14-galaxy group, most aligned in a N-S string.  I drew 5 galaxies in my sketchbook: 382, 380, 379, 385, 384, though a couple of what I took to be stars might have been small galaxies, but I didn't count those.  They all appeared as small elliptical glows of varying size, brightness, and orientation, and it was neat to see them in a string like that.

IC 342: a soft, moderately large round glow, seen best with gain turned down low.  I sense some swirling effect in the mottling, especially near the center bright stellar core, but it is very subtle.  NV does not do well with face-on galaxies.

NGC 891: This was very large, a bit more than the FOV, and very ghostly, seeming to float in the dense field of stars.  Faint, long, with a prominent dark lane down the center.  

NGC 910 group: Just a half degree to the southeast from NGC 891 is NGC 910 and friends, a string of five brighter NGC galaxies, plus a couple more very faint and small NGC and MCGs.  910 was the brightest by far, then leading north like breadcrumbs were 911, 909, 906, and 914 off to one side.  These all appeared as small elliptical glows in various orientations.

NGC 80 group: Another cluster of galaxies of which I saw eight: 80, 83, 90, 93, 79, 85, 86, 96 all as small elliptical glows, except for 90 which was slightly mottled and round.

NGC 772: This is a disrupted spiral and appeared so: a bright core off-center to a diffuse comma-shaped halo with a long bright arm, which I could clearly see, to the north.  Smaller, fainter elliptical NGC 770 was close by to the southwest. 

NGC 200 and others: Another string of galaxies, this time seven in the field of view (193, 204, 199, 194, 200, 198, 182), all pretty bright oval and round glows except for 199 which was smaller and fainter.

AGC 426, Perseus Galaxy Cluster: when centered on NGC 1272, I can see more than 15 galaxies in the field with direct vision, and a few more with averted vision.  Several bright ones, then smaller non-stellar glows appear.  This view more than anything convinces me the night vision device really does triple the effective aperture!

NGC 1023 / 1023A: One of the more dramatic galaxies seen.  Very large, bright, very long arms extending beyond the FOV, and swirly dark nebula around the core.  The eastern tip had a brightening which is elongated at a slight angle than the main galaxy, this is 1023A, its satellite galaxy.  Too bad Jamie wasn't there to have a look!

It was at this point I remembered how night vision does particularly well with flat galaxies, so I pulled out Alvin Huey's Flat Galaxy Observing Guide and observed some I hadn't looked at before:

NGC 100: Lovely long galaxy at least 8:1 NE-SW, with a bright central core and a halo which gently tapers to very fine tips.  Vmag 13.9, size 5.4 x 0.6'.

NGC 522: Small but bright, with a very bright core and long tapering tips, 6:1 NE-SW.  A string of 3 fine stars just north of the galaxy.  Bmag 13.9b, size 2.7 x 0.4'.  Did not notice IC 102.

IC 194: Difficult, very faint, small but very extended streak nearly N-S, slightly brighter round core.  Mag 15.2p, size 1.4 x 0.2'.

IC 176: Very difficult, extremely faint, needed to check the star pattern in the guide to locate it.  Small 4:1 E-W glow with a very faintly brighter core.

NGC 973, with IC 1815 in field: 193 looks like a smaller version of NGC 891, edge-on and bisected by a dark lane, 6:1 NE-SW, Mag 13.6p, size 3.7 x 0.6'.  IC 1815 was a small out-of-round glow with a brighter core.

NGC 1110: Extremely faint, needed to play with the gain setting to detect it: weak glow NNE-SSW, 5:1, very slightly brighter central region and diffuse, very faint tips.  Mag. 15.0 2.8 x 0.5' 

NGC 1145: Fairly easily seen, in an "L" shape asterism of three equal magnitude stars, 6:1 NE-SW, it has a compact bright core, and the halo is mottled -- I have the sense it is slightly inclined towards us showing some spiral structure.  Mag 13.6b 3.2 x 0.5' 

NGC 1163: Very faint, lays off of a triangle asterism.  Brighter bulging core region quickly fading to sharp tips.  Mag 14.7b, size 2.8 x 0.3' 

NGC 1247: Pretty bright, very bright core, mottled inner halo, diffuse tips, 6:1 ENE-WSW.  Mag. 13.5b 3.3 x 0.5'.

IC 2098: Extremely faint, small, 6:1 E-W, with a slightly brighter round core which bulges from the halo.  Mag 14.5, size 2.5 x 0.2' 

NGC 925: face-on barred spiral, appeared as a fairly large, faint mottled glow with a small bright core and a brighter smudge in the halo glow extending E-W from the core.   

NGC 253: Probably the sight of the night: Gigantic galaxy filling more than the field of view, very mottled halo with swirls of dark nebula around the core.

27 august 2025

Observed with the 6-inch, pretty good seeing for the aperture, some haze.  I went back to using the zoom eyepiece for the connivence.  

BU  692 AB: 152; 250x: Very close B seen intermittently with seeing, very difficult.  -37% PRO, it is not binary.

21h 50m 05.37s +31° 50' 52.4" P.A. 10.00 sep 2.9 mag 7.47,11.03 Sp K0 dist. 181.16 pc (590.94 l.y.)

BU 1516 AB: 152; 125x: Wide and faint, three similar stars in a wide triangle around the primary.  Lacks parallax data.

22h 41m 27.67s +10° 49' 53.0" P.A. 145.00 sep 57.0 mag 3.38,11.60 Sp B8V dist. 62.66 pc (204.4 l.y.)

ES 1028 AB: 152; 180x: Moderately close B seen with foveal coaxing, large delta mag.  35% PRO, 1,336 AU WS, 2.6+1.2 Msol, but RVD 2.7 > EV 2.2, it is not likely binary.

22h 42m 24.05s +54° 14' 54.3" P.A. 243.00 sep 6.0 mag 7.58,10.57 Sp A0V dist. 208.77 pc (681.01 l.y.)

HJ 1756 AB: 152; 180x: Very pretty, with averted vision the system looks like a planet and moons, one on either side, one close (AB) and other father and off kilter (AD).  Can hold the faint stars better with higher power.  B lacks parallax data, A and D don't overlap.

22h 21m 52.83s +40° 39' 59.1" P.A. 286.00 sep 22.3 mag 6.69,10.49 Sp K3.5III dist. 165.02 pc (538.3 l.y.)

HJ 1791 AB: 152; 125x: Wide, 2 Dm.  43% PRO, 1,016 AU WS, 1.3+0.8 Msol, and RVD 1.9 = EV 1.9, 0.08 PMV, it is possibly binary and needs an orbit.

22h 35m 39.29s +56° 51' 40.2" P.A. 59.00 sep 17.1 mag 7.71,9.69 Sp G0

STF2881 AB: 152; 250x: Close split, unequal.  11% PRO, 194 AU WS, 2.1+1.8 Msol, it is likely binary.  SOC grade 4 orbit, 1345-year period.  

22h 14m 34.67s +29° 34' 20.6" P.A. 75.00 sep 1.3 mag 7.65,8.24 Sp F6III dist. 171.53 pc (559.53 l.y.)

STF2908 AB: 152; 125x: Wide, dull white and light orange, 2 Dm.  4% PRO, 2,139 AU WS, 2.7+1.7 Msol, 0.09 PMV, it is possibly binary, an orbit can be tried.

22h 28m 11.55s +17° 15' 47.9" P.A. 114.00 sep 9.1 mag 7.74,9.68 Sp G9III dist. 462.96 pc (1510.18 l.y.)

STF2948 AB: 152; 250x: Very pretty light white and blue stars, close split, seen with 125x, but nicely seen 250x, 2 Dm.  -18% PRO, it is not binary.

22h 49m 36.21s +66° 33' 13.8" P.A. 3.00 sep 2.6 mag 7.26,8.60 Sp B6Vn dist. 261.78 pc (853.93 l.y.)

STF2950 AB: 152; 250x: Hairline split high power only, very unequal.  73% PRO, 102 AU WS, 1.6+2.2 Msol, but -0.03 PMV.  SOC grade 4 orbit, 817-year history, time will tell.

22h 51m 22.51s +61° 41' 47.9" P.A. 270.00 sep 1.1 mag 6.03,7.08 Sp G8III-IV dist. 72.73 pc (237.25 l.y.)

STFA 58 AC: 152; 70x: Superwide, 2 Dm.  49% PRO, but 11,624 AU WS, 6.7+3.9 Msol, but RVD 3.1 > EV 1.3, it is not binary.

22h 29m 10.25s +58° 24' 54.7" P.A. 191.00 sep 41.0 mag 4.21,6.11 Sp F5Iab+B7 dist. 265.25 pc (865.25 l.y.)

STT 458 AB: 152; 380x: Hairline split, unequal, suspected double with lower powers.  29% PRO, 274 AU WS, 3.1+2.3 Msol, 0.09 PMV, it is possibly binary and needs an orbit.

21h 56m 27.30s +59° 47' 42.4" P.A. 349.00 sep 1.0 mag 7.20,8.41 Sp A0V dist. 346.02 pc (1128.72 l.y.)

STT 467 AB: 152; 250x: Light orange star very wide faint B seen averted vision only with 125x, can hold it with 280x.  RVD 4.7 > EV 1.2, it is not binary.

22h 14m 48.57s +22° 31' 24.3" P.A. 273.00 sep 23.0 mag 6.73,12.20 Sp G8III dist. 220.26 pc (718.49 l.y.)

STT 470 AB: 152; 125x: White and light blue stars, close separation with low power, 3 Dm.  8% PRO, 492 AU WS, 1.9+1.0 Msol, RVD 2.3 < EV 3.3, 0.07 PMV, it is possible to be binary, an orbit can be tried.

22h 20m 57.68s +66° 57' 54.5" P.A. 351.00 sep 4.3 mag 7.37,9.77 Sp A7V dist. 104.82 pc (341.92 l.y.)

STT 480 AB: 152; 125x: Wide near equal pair, near an open cluster, which is a few brighter stars and a glow of unresolved stars.  10% PRO, 1,942 AU WS, 1.4+1.1 Msol, RVD 0.9 < EV 1.5, 0.08 PMV, it is possible to be binary, and needs an orbit.

22h 46m 05.29s +58° 04' 19.6" P.A. 117.00 sep 30.7 mag 7.65,8.64 Sp F8

STT 481 AB: 152; 250x: Lovely close spilt with low through high powers, white and blue, 2 Dm.  4% PRO, 576 AU WS, 2.8+1.7 Msol, 0.07 PMV, there is some chance it's binary, an orbit can be tried.

22h 43m 50.72s +78° 31' 05.7" P.A. 277.00 sep 2.2 mag 7.46,9.54 Sp A0II-III dist. 390.63 pc (1274.24 l.y.)