Observation report from September 5, 2013, with the 30-inch Dobsonian

From the green beacons of the summer Milky Way to galaxies in the autumn sky.

Based on the weather forecast for the Alpine region, we decided against a trip to the Alps on Thursday, September 5th, and opted instead for a night of stargazing in the local fields.

The rural Swabian sky—located 60 km northwest of Stuttgart—cannot compete with the famously excellent skies found in alpine ranges; it falls short by nearly a full magnitude in limiting magnitude.

Yet, with a limiting magnitude of a good 6.0, a clear 360-degree view, and no lights in my field of vision, I hear no one in the Swabian Forest complaining.

Exceptionally good weather conditions were already evident on Wednesday, but work commitments meant I was only able to get out under the starry sky on Thursday.

While setting up our 30-inch f/4 Dobsonian, we could clearly see the Earth's shadow on the western horizon before dusk. This raised hopes for one of those good nights of observing—now a rarity—in the Swabian Forest.

My battery of wide-angle binoculars—comprising 8x60mm (11° FOV), 11x80mm (7.5°), and 20x120mm (4.2°) models mounted on a Giro head and a surveying tripod—was set up alongside the 30-inch telescope. My  "astro-chair" plays a major role in making observing with all this equipment comfortable.

Uli brought along his beautiful 15-inch Discovery Dobsonian, while Mike brought his "grab-and-go" scope—a Sky-Watcher 120/600 comet hunter. Dennis and Micha rounded out the observing team for this extended evening session.

Venus was the first object to catch the eye, appearing low in the southwest early in the evening. We used Venus to align the 8" f/5 finder scope and the Telrad on the 30-inch telescope. On that night, we used the following eyepieces with the 30-inch: Nagler 31mm (100x), Ethos 17mm (170x), Ethos 10mm (305x), and Nagler Zoom 3–6mm (500–1000x).

While setting up the wide-field telescopes, I located the Butterfly Cluster (Messier7) above the treetops to the south. Once it had grown a bit darker, I observed M13 with the 30-inch telescope and located Messier24 using the wide-field telescopes.

While the large telescope was still cooling down, the star images weren't yet perfect; nevertheless, M13 was well resolved right into its core, and the three dark lanes of the "Propeller" feature stood out clearly at the 5 o'clock position.

After everyone had drooled a little over the Dobsonian's ladder, the telescope was slewed to the nearby galaxy NGC 6207. It appears elongated and slightly mottled, with a bright center.

Through the smaller wide-field telescopes nearby, the beautiful gas nebulae Messier17 and Messier16 could be seen in the same field of view alongside the small Sagittarius Star Cloud (M24). Enjoyed while sitting comfortably and relaxed on the "Füssen astro-chair," such a sight within the summer Milky Way is a true delight for the optic nerve.

And that was what mattered to us that evening, too: not necessarily seeking out the faintest flickers of light, but seeing and enjoying!

Using the 30-inch telescope, Mike targets the Turtle Nebula (NGC 6210) in Hercules. At magnifications of 170x and 300x, shell-like structures are visible within an ice-blue, oval planetary nebula. Faint traces of four appendages surrounding it can also be seen.

I slew the big Dobsonian toward Canes Venatici and center Messier 51 before it sinks too low in the northwest. At 170x, it is a visual delight in the 30-inch f/4 scope. Distinct spiral arms with knot-like condensations—along with the 90-degree bend in one of the arms—thrill the observers.

Micha slews the Dobsonian further north in azimuth and targets M81 and M82. In the 30mm eyepiece, both objects reveal beautiful details that any observer would love to see.

For comparison, Uli has trained the 15-inch telescope on the same objects. In the 15-inch f/5 scope, both objects are still visible within a single field of view.

The North America and Pelican Nebulae are observed side-by-side in the 120/80/60mm wide-field telescopes, both with and without a UHC filter. The Cirrus Nebula, viewed in its entirety, impresses in all three telescopes.

NGC 6309, the Box Nebula, is targeted using the 30-inch telescope; true to its nickname, it appears as an elongated, almost rectangular object. Unfortunately, as it is already positioned rather low in the southwest, hardly any hint of color is discernible.

In the 30-inch telescope, NGC 7027—the "Magic Carpet"—appears as a brilliant green, oval planetary nebula (in the constellation Cygnus). Just for fun, I crank the magnification up to 1000x using the Nagler zoom, but even at 500x, the stars appear somewhat bloated due to atmospheric seeing. I then put the zoom eyepiece back in the case.

The beautiful planetary nebula PN 6818 in Sagittarius is the next object. Perfectly round and pale green with dark shadings within the nebular bubble, the PN is revealed by the 30-inch telescope at magnifications of 170x and 300x

Afterwards, I pan a little to the south and spot NGC 6822—Barnard's Galaxy—as an oval shimmer.

Messier 74 is located in the constellation Pisces. At 170x magnification, the beautiful spiral arms are directly visible.

Mike says his goodbyes around midnight, and as a final object of the night, we aim the telescope at the Helix Nebula (NGC 7293). It is barely discernible without a filter, but with a UHC filter at 100x magnification, it appears as a flattened ring occupying half the field of view, looking brighter along its northern and southern edges.

Dennis also has to head off, and after we regain our dark adaptation—having been disturbed by departing cars—we make our way up to the southwestern corner of the Great Square of Pegasus. We then locate the beautiful galaxy group comprising NGC 7454, 7448, and the NGC 7463–64–65 complex.

Next, the telescope is slewed southeast toward Pisces. NGC520 and the triplet NGC 467-70-74 are targeted. First, NGC 520—the "Chromosome Nebula"—appears as a large, elongated, irregular object with a dust lane. With a bit of imagination, one can make out a helix shape. Two fields of view further west, the NGC 467-70-74 trio comes into view.

The beautiful barred spiral galaxy NGC 7479 is our next object. At 170x magnification, the spiral arms are visible via averted vision, appearing like little hooks at the ends of the central bar. However, the view through the 30-inch telescope in the "Swabian Outback" is at least two classes inferior to the view last September with the 16-inch scope at the Roque on La Palma. There, those little hooks seen in with direct visioning good contrast!

I am now slewing to IC 63 near Gamma Cassiopeiae; I’m curious to see what our "Big Guy" can reveal under the home sky. Now we're getting somewhere!  An arrowhead-shaped nebula is relatively easy to spot east of Gamma; using a UHC filter makes the nebula stand out a bit more clearly against the background. Not far away, I locate IC 59, which is harder to make out.

For a change of pace, Micha has targeted Kemble's Cascade with the WW telescopes. I like the view best through the 11x80s. The stars shine like a waterfall of glittering gemstones.

This is a good opportunity to slew the Dobsonian to the planetary nebula NGC 1501. At 300x magnification, the planetary nebula appears grass-green, featuring a brighter, broken rim and a clearly visible central star.

We slew up to Perseus and center on NGC 1275, the brightest galaxy in the Perseus Cluster. Even in the finder eyepiece at 100x, about ten galaxies are visible alongside the target object; with slightly higher magnification, they stand out more clearly. They line up across the field of view like a chain.

M76 is the next object of my desire; at 100x magnification, the planetary nebula appears with a greenish hue, while at 300x, the thickenings along the rim of the shell—which gave rise to the name "Little Dumbbell Nebula"—are clearly visible. Parts of the outer halo can be glimpsed.

The contrasting sight in the wide-field telescopes is h & Chi. In the smallest pair—the 8x60s—the "little muscle man" also appears within the field of view.

By sweeping widely toward Cygnus—already positioned in the west—PN 7008 is brought into view. At 170x magnification, it resembles an earlobe with two pierced stars.

In Cepheus, we particularly enjoy the Iris Nebula (NGC 7023) in the 30-inch telescope, with its delicate bluish glow and clearly discernible dark structures.

The Orion Nebula is already glowing faintly in the light of the waning moon, while I search for Comet ISON just beside the Beehive Cluster—which is currently rising—though unfortunately without success.

Afterward, I sacrifice my dark adaptation by looking at Mars, positioned close to the Beehive.

Suddenly, around 5 o'clock, an older visitor appeared; he had heard from evening strollers that telescopes had been set up there. He showed interest but was somewhat reserved.

We invite him along and share the final hour of this beautiful night with our visitor—taking in the magnificent wings of the Orion Nebula and wide-field views of the Pleiades and Perseus—before dazzling our eyes at dawn with Jupiter through the 30-inch scope, which revealed abundant detail in the cloud bands, razor-sharp even at 300x.

As the 30-inch is loaded into the trailer, Sirius—visible in the bright morning sky—winks at us. Thanks to Uli and Micha, who put up with me until the break of dawn.

On the drive home, I found myself thinking: Jones-Emberson 1, G1, the Silver Dollar Galaxy in Sculptor, and so on... ...you didn't get around to pointing the scope at those tonight.

It’s great when, after such a fantastic night, there are still plenty of targets left for the next

Uli & Mike are collimating the 8"F5 Finder scope with the main Instrument, our 30"F4 Dobsonian.

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