MM Prelims, and Planets in the twilight

by Robert Leyland


Observer Robert Leyland
Date 17-18 March 2001
Time 1800-0130 PST (UT -8, or 0200-0930 18 Mar 2001 UT)
Location Lake Sonoma CA, 38°43'N 123°02'W Elev ~1400 (Lone Rock Flat)
Weather 16°C (falling to 10°C) 69% Humidity (rising to 95%) High altitude cloud cover early evening cleared by 9pm
Seeing LM 6, transparency 7/10, Bortle:4
Equipment 8" F6 Dob, Telrad + 7x50 finder scope, Pentax XL EPs 15x70 Bear binoculars

In the early evening, my plan was to hit the twilight Messier objects in preparation for next weekends Marathon. However cloud clover denied me most of those targets, but left the planets alone. Before the sun had set, both Venus and Saturn were clearly visible, and made excellent viewing targets.

Venus, has a lovely crescent, as sharp as the new moon, but with a rainbow hued lower edge, from atmospheric refraction. Early in the evening the full planetary disk was apparent, but as the sky darkened the light of the bright crescent overwhelmed the low contrast planet.

Jupiter was majestic, with band visible in the twilight, and four moons. As I watched one moon was occulted by old Jove, a bright spot that glimmered and was gone.

M42 is an interesting twilight sight. The wings of the nebula are quite prominent, even when the sky is blue!

Saturn also showed nicely, at 7pm three moons were visible, along with the Cassini division, and the shadow of the planet on the rings. Averted vision allowed me to see other moons, and the sunset wind jiggled the telescope, making them both harder and easier. Easier to detect, but harder to discern.

David Staples arrived, and setup his C-8, but the cloud cover almost sent us packing. David has only had his 'scope since January, so this was one of his first good opportunities to use it. We spent some time chatting, and around 8:30 the clouds started to clear, by 9pm they were gone for good.

Together we went looking for a variety of easy Messier objects. I still wanted to catch the early marathon Ms, and David had a target list from "Turn Left at Orion".

M74 -- after twilight, very close to the horizon, little more than a smudge. It had been covered by clouds earlier, but I was able to catch it before it set.

M31,32,100 -- the big galaxy was pretty easy even though they are very low in the sky, M32 wasn't difficult, but 110 was pretty faint.

We hit many of the highlight objects, to give David more practice pointing the C-8, and I enjoyed myself since it had been a while since we had even halfway decent weather. I didn't log any comments on the following objects, but we did see them all, and David was able to find many of them himself.

M1, M42/43, M65/66, M51, M81/82 (surprisingly bright), Pleiades, Hyades, M44 and the Double Cluster. Cor Caroli and NGC 2362.

We spent a bit of time finding and verifying the "clown face" nebula NGC2392 in Gemini, and then looked at M35, with its thumbprint sidekick NGC 2168.

David wanted to see a globular cluster, and M68 was the first I could find. It was a little depressing as Corvus was still pretty low, and in the SE light dome.

I haven't done much observing in Canis Major, so as we hit the Big Dog Ms, I did make a few notes.

M46/M47 are a nice pair of contrasting open clusters one bright, loose and open; the other large faint and dense. M48 is also a loose open cluster.

M67, an open cluster in Cancer, by comparison is tight and compact.

In Leo, I'd already hit the easy M65/66 and shown David how to find them on the lion's hind leg. I was expecting M95/96 to be similarly close, and got confused when I found M105, as the companion galaxies were quite bright. When I checked the charts, I realised my error, however it surprised me that Messier didn't include NGC 3384 in his list, as it is nearly as bright as M105. The other companion, NGC3389, is fainter but still clearly visible. M95 and M96 are lovely bright elliptical galaxies.

Off to Canes Venatici, and now following Pennington's marathon list, I went for M3, a nice globular cluster, much nicer than M68 seen earlier. As David was packing up, I was happy to show him good globular cluster.

M63 is a nice galaxy with a bright star adjacent.

M94 has a bright circular core.

M106 is a nice elliptical galaxy, with a nearby faint ellipse also visible.

Last year, with a lot less experience, I got stymied in the Coma-Virgo group. With another year of experience, and a little more determination I wasn't going to get lost in Berenices' Hair :-)

Next to an interesting asterism is M53, a globular cluster, and of course now I remember why I got into trouble. I kept getting distracted, CV is a fascinating area of the sky, containing the galactic pole and more galaxies than you can shake a stick at.

M64 (Com) is a really nice compact oval galaxy, with a hint of a dark patch. This was clearer with averted vision. One more I'd like to come back to after the marathon.

M85 is a small compact galaxy with what looks like a second core bright spot, and a dim companion galaxy.

In Virgo M104 is looking fine tonight, the dark lane is quite obvious.

M61 has a nice circular shape, and averted vision shows a nice bright spot at the core.

M49 has an even nicer circular shape, and again averted vision shows a second bright spot, also there are several adjacent galaxies. This is a busy region.

M59 and M60 off Vindemiatrix (which sounds like it should be a character in "Asterix the Gaul") form a very nice cluster of galaxies with companions NGC 4647, and 4638.

M58 is just one small step further and has a nice core next to a bright star.

M89 and M90 I can recognise from the pattern of stars around them, M89 is circular but not as bright as the oval M90, Nearby, and surrounded by a distinctive L pattern of stars, is M91 a dimmer oval galaxy.

M88 (Com) is a nice oval galaxy next to a double star.

M87 has a circular shape next to a bright star, and NGC 4478 is also visible.

M84 and M86 are a nice pair of galaxies, and form an equilateral triangle with much fainter NGC 4387, off to the side, but out of the FOV is another pair of galaxies NGC 4413 and 4438, quite cool!

Climbing north back to Coma Berenices brings us to, M99 which shows a circular shape and has a bright star adjacent.

M98 is knife edged and cool streak next to a very bright star (6 Com)

M100 is a larger circular galaxy, with an easy adjacent star. Just beyond this star is another much smaller fuzzy area, NGC 4312.

At this time (1:10AM) the humidity has climbed to 97%, and some dewing has hit the binocular handles, the book covers, and some papers are a little damp. It also dropped to 10°C which is relatively warm compared with last months observing, but the chill is there all the same.

All in all, a very successful evening, a good twilight session, and I made it through the Coma-Virgo group quite happily.

I'd rather spend a little more time on each object, but for the MM it's just seeing, and verifying them that counts, and on that note I counted 45 Messier objects seen. Maybe I'm ready for the Marathon next weekend.