Log, Feb 18, 2001

6 people. After 16 of 18 rainouts this winter, we just couldn't pass up the chance to crank up the 16" SCT at FDO. We declared a "Virtual Friday Night" and sent out the alert to anyone we could reach in time. Six of us showed up including two invited guest from Southern New England Astro, Steve Brandt and Dave Aucoin. Regulars included Joe, Les, Doug and Barry.

Skies were excellent, starting with a few small clouds which dissipated quickly as the off shore wind evened the water and air temperatures. The wind dropped by 8 PM and the seeing was very stable. As always, there was a horizon sky shine in the northeast from Providence and Warwick with a lesser illumination to the west from Westerly, Groton and New London. These horizons were something like a 4.5 on the Bortle scale but the southern horizon and overhead were much closer to 2.5. I could just see 6.25 stars with averted vision (using my favorites in the Pleiades as guides). Extended objects were clear, and the Orion Arm (the thin section) of the Milky Way was very clear. It was dark enough that Venus cast a discernible shadow outdoors and Jupiter cast a shadow if we turned all the lights off in the Dome. Temperatures ranged from 30 at 7 PM to 23 at 3:30 AM.

We saw several special events throughout the night. As predicted, an Iridium satellite passed through Orion at magnitude -2 (about as bright as Jupiter). Two other satellites crossed shortly after followed by the International Space Station (ISS) which moved from the west across our northern sky and then passed into shadow. Just before it winked out, it turned an orangy-red from light scattered by the atmosphere. Although we were not expecting any unusual meteor activity, we saw at least ten or twelve including two moderately bright streaks. The activity was primarily between Canis Major and Orion, but the radiant if any was not deducible.

FOR THE LOG, we officially bagged four more Messier objects for which we had no prior log record since the new SCT was installed in July of 1999. These included the cluster M50⊗, and the galaxies M94⊗, M106⊗, and M109⊗. We now only need to wait for 5 more messier objects before the 16" has completed a piecemeal Messier Marathon. Of these four, M106 was the best but only by the tiniest of margins over M50.

Dave Aucoin set up his 13" Dobs once he managed to move his truck into position. Something in the truck caused it to stall out almost as soon as it was started. Luckily this problem went away as the truck cooled. Dave also had some collimation problems with his diagonal mirror which required tools none of us thought to bring. Ever use battery cables as pliers? Well Dave did with fair success. Dave likes to look for Abell planetary nebulae. The rest of us took period sojourns out of the Dome to get a peek at Dave's latest object. He has a nice scope.

After Joe did an alignment (needed after being left untouched for almost three months), our first target was Saturn. We could see six of the seven brightest moons. Only Mimas was hidden. The Cassini Division flashed into a complete oval as faded as we watched. The Crepe Ring was evident against the planet. We had hints of the Encke Division but I would hesitate to affirm that we truly saw it.

M42 was spectacular with great swaths of gas. We could easily see not only the four bright stars of the Trapezium but "E" as well. "F" winked on and off but remained hidden most of the time. We looked at M35, NGC2204⊗ and NGC158⊗ while we were pointed towards south. NGC158 is a clusters composed of stars cataloged down to 15.5. These were seen clearly as well as additional stars we estimated were close to the 17th magnitude by the contrast method. We went after our old friend the Eskimo Nebula NGC2392 and the nearby rich cluster NGC2420⊗.

In went the Hydrogen Beta filter - time to look for the Horsehead Nebula (IC434). The Horsehead is tricky to see. First of all, it is dark and our eyes wish to look at bright things. Secondly, the surrounding "light" is a very dim red light (the Beta emission line of hydrogen) which at first glance is simply very dark gray against a slightly darker gray. Using our standard procedure, we each looked at the image before we compared notes. This precludes one of us prematurely influencing another's view. We had some disagreement initially about whether the head was looking to the left and down or to the right and up. A second review resulted in a consensus that the head was looking right and up. This was confirmed by Sky Pro 6. The image of the Horsehead to the right is a reasonable representation of what we say at the eyepiece. Astronomy books often show a dark black chess set like horse's head against a bright pink background. The human eye is unable to see color when it is as dim as IC434 so that only the rods pick up anything giving a black to white image. Contrast was even lower than my photo manipulation software would suggest. If it wasn't such a famous object, I doubt we would care much if we saw it or not.

We also looked at NGC3945⊗, NGC2354⊗ and the very nice τCanis Major Cluster NGC2362. Doug remembered a suggestion from Sky and Telescope so our next target was the gorgeous double star HD56577⊗ with a yellow gold 4.6 star paired with a blue green 6.8 star. It was very similar to the famous double Albireo. We spent time examining the rich starfields around ξPuppis⊗.

We started knocking off a sequence of Messier objects old friends as well as a couple of possible first timers. M81 and M82 were in a single wide view. M82 was spectacular at high power. The Owl (M97) was next, the M108, M109 and M106 which is a very nice galaxy. We looked into the Whirlpool M51 and the only words to explain it is WOW. After M51, poor M101 wasn't as great. M3 was stunning. the triple M66, M65 and NGC3628 were beautiful as were a second triple M105, NGC3684⊗ and NGC3389. Doug split Cor Coroli in Canes Venetici. M104 was beautiful, M94, NGC5005⊗, NGC5033⊗ and M63 were next.

We took a breather to scan the skies and study Praesepe M44 through binoculars. This cluster is wonderful - the best thing in Cancer. To the south the usually insignificant "Crater" constellation formed a keystone similar to the more famous keystone in Hercules which was by now well up in the sky. With Hercules in view we turned to M13 and the almost as stunning M5. If you haven't seen these wonders, run, do not walk, to your nearest large telescope. Enough said.

Doug swung the telescope below M13 and instantly found Comet McNaught Hartley⊗. [No, sorry the comet's finder ISN'T our very own Technical Director Joe Hartley.] The comet was of minor interest.

On we went, M92, NGC6209⊗ (a globular), NGC4361 (a planetary), NGC4038⊗, NGC4027⊗, NGC3115 (the Spindle galaxy), NCG2974⊗, and NGC3521 (a barred spiral) went by as fast as we could target them and get a good view. We looked at the very orangy variable star V Hydra next. Someone shouted Mars is clear of the trees. Well it was clear of the trees but it was a poor sight so close to the horizon. We turned to the fine bright double star β2Scorpio. Its two elements at 21 arc seconds apart, one at magnitude 2.6 and the other at 4.9.

We were all getting quite tired. We already stumbled over and broke a wall socket, and had dropped some screws in the focuser control while changing batteries, so we knew it was time to start wrapping up. Our final target of the night was the Ring Nebula in Lyra M57. Hey! Isn't Lyra a SUMMER constellation? Well yes, but if you stay up late enough (3:30 AM) it is also a Winter constellation. By my count we saw 3 planets, the shadows of 2 more, 6 moons, 4 satellites, 59 DSOs, about a dozen meteors and scads of stars. 19 DSOs were first timers, never viewed by our telescope before. Not bad for an impromptu night.

⊗ First time viewed through Meade 16" SCT at FDO.

-Les Coleman

Leslie Coleman
Leslie Coleman
Entry Date:
Feb 18, 2001
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Leslie Coleman's Log
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