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by Jerry Spevak The key luminaries of the autumn sky are shining brightly. The Summer Triangle still rides high in the northwest, while Fomalhaut twinkles in the south. In passing weeks these beacons will disappear from the evening sky, and already to the east, Capella and Aldebaran are foreshadowing long snowy nights. Tonight, Kwai and I seem to have the whole of Oak Heights to ourselves. Kwai is already searching out Messiers with her binoculars, so I'd better get moving. The 7 cm apochromat I observe with is a breeze to set up and use. A sturdy video tripod serves as its mounting, and I run objective and eyepiece heaters from a compact 12 volt battery. These handy devices prevent dewing on even the most damp nights. All controls and accessories are close at hand -- there is nothing worse than fumbling around in the dark (with a telescope, that is). It's fun to have a look at a double star or two, before it gets really dark. Albireo marks the beak of Cygnus the swan. Here we find magnitude 3.1 and 5.1 suns 34 arc seconds apart. The primary is golden yellow and the companion is blue. This pair is wonderful at low powers. The North America Nebula lies just east of Deneb in Cygnus. This expansive object was discovered by William Herschel in the course of his great survey of the heavens. Considering the high magnifications he regularly employed for his sweeps, it's surprising he didn't pass right over this enormous object. Large faint nebulae are no problem for the refractor. With a 56 mm Super Plossl, at 9x, the nebula is just plain obvious. Numerous stars are scattered across its face. These stars are noticeably absent from the dark regions surrounding the nebula. In reality, we're seeing the effects of thick obscuring dust clouds. The view with an OIII nebula filter is even more spectacular. Although the stars are greatly diminished, the nebulosity really jumps out. Dark lanes and luminous patches abound. The much fainter Pelican Nebula is visible in the same field a little to the west. Cygnus has many interesting nebulosities, perfect for a rich field instrument. Another of Herschel's discoveries, the Cygnus Loop is a huge supernova remnant near 52 Cygni. As I slew the scope to the right field, the OIII is still in place. I'm truly blown away by the view! Being used to a large Newtonian, I've never beheld such wide angle, yet detailed panorama. The entire bubble easily fits into the field. Both main arcs are broken into minute filaments, and the inside of the bubble is filled with detail. Switching to a 20 mm Nagler, at 24x the whole Loop is still visible, but the arcsecond detail is hard to describe. I look skyward in time to catch a bright Perseid shoot through Draco. On perfect nights like these I can't help having a look at the Great Hercules Globular. It's one of Kwai's favourites. Low power reveals only a fuzzy ball. With the 20 mm Nagler, a few stars are resolved. A 4.8 mm Nagler at 100x shows a lot more, perhaps a few hundred. Since we are only reaching down to about 14th magnitude, the vast swarm of 15th and 16th magnitude stars on the horizontal branch of the H-R diagram are not resolved. This is why this cluster looks so much better with only a doubling of aperture. The bright spiral NGC 6207 lies in the same high power field, and its mottled core is evident. M 92 is a hop away. It's only half the size of M 13, but it has its own special charm. With a 7mm Nagler at 69x, the core appears very compressed and is difficult to resolve. The outer ramparts are readily broken into a hundred shining jewels. My all-time favourite roster includes two objects in Lyra. The Ring Nebula always takes my breath away - - a delicate smoke ring among a rich starfield. The ring shape is evident at 9x, but 100x provides a better view. The interior is filled with faint light, and the ring exhibits subtle variations in intensity. The Double-Double, Epsilon Lyrae, is a treat. High power reveals four white bullet holes in tight formation. In a 7 cm aperture, the size of the diffraction disk (at half of maximum) is 2.0 arc seconds and these two pairs provide a good test of resolving power. The northern pair consists of 5.2 and 6.3 magnitude components currently 2.7 seconds apart. The south pair has 5.1 and 5.4 magnitude stars 2.3 seconds apart. Who can resist a peek at the Dumbbell Nebula? Not me, so here we go. The distinctive lobed profile is evident at 24x and the 3 degree field is full of stars. Very rich indeed. Many stars are visible against the nebulosity itself, but the central star is out of reach. In a 32 cm Newtonian, this central luminary is distinctly blue. How do you find it? The Dumbbell responds very strongly to an OIII filter, revealing an intricate mottled structure at 69x. The Pleiades are already high in the sky and deserve a visit. At 24x they're framed nicely. Innumerable sparkling gems fill the field. All are bluish white except for one. Near the centre of the main trapezium lies a wide equal-magnitude double star. Careful attention will reveal the western component to be distinctly ruddy -- a solitary ruby on a velvet of sapphires. Tonight, the entire cluster is bathed in ribbons of very faint nebulosity. As always, the portion south of Merope is especially prominent. Often, a dewed objective will produce the same nebulous effect. The nearby Hyades provide a good check for this. If they too are bathed in haze, you have a problem. It's been a long night, and it's getting late. Time to hit the sack and dream of distant wonders. As the gentle breeze lulls us to sleep we find ourselves wondering if the famous Oak Heights Grizzly Bear will pay us a visit. Right Paul? Just kidding. |