Observation Report - September 30, 2005

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The evening of September 30, 2005, was incredible. My wife, two kids, and I packed things up for a stargazing field trip to Cinder Hills Overlook at Sunset Crater National Monument. This site is a cul-de-sac at the top of a hill with a beautiful view of the surrounding forest, lava flows, and Sunset Crater itself. As things usually go, there was a lot of running around and hasty gathering of all the tools and comforts that go into a family outing in the dark of night, so that one might get there before it gets completely dark. The Cinder Hills Overlook site has turned out to be a great observing spot for me in a few ways. It's a short 15 minute drive from our house, but as close as it is to town, the sky is wonderfully dark. M33 is a naked eye ghost, the Milky Way is broad and mottled, and all those faint in-between stars are there for the picking.

There is a light pollution bubble from Flagstaff to the southwest, but the majority of it is blocked by the looming bulk of Sunset Crater's conical mass.

This does hide the west and west-southwest horizon from view, but as long as you're not planning to observe that 5% of the sky in the absolute moments after twilight, it's not really a problem. Another bonus is the lack of traffic, especially in comparison to Anderson Mesa (another incredible site, and even darker), where there seems to be a lot of traffic, both to the observatory, as well as campers and smoochers looking for a place to park. The one problem is that due to cold air drainage from the San Francisco Peaks, it can get pretty windy around Sunset Crater.

And so it was that evening. It bit breezy, but not irritating or gusty. The night was cool, but not cold, and it was so pleasantly quiet. My wife got the lawn chairs, snacks and drinks set up while I set up the telescope and assorted tools and reference materials. To compliment the flowing Milky Way, we were treated to a regular bounty of meteors and slow moving satellites. After getting the scope polar-aligned, I lined up on our first sight of the evening, the bright, brilliant open cluster, M7. It was nice to have the kids out at a dark site, since observing in front of our house usually means calling them outside where they have no real chance at dark adaptation. So they were able see objects that can't be managed under poorer conditions. (Not that M7 was one of those.) We moved on from there to the globular M22, the Lagoon Nebula M8, and the Swan Nebula M17. The nebulosity around M17 was simply expansive. I didn't choose to make a sketch this time around, but there is far more to see than my sketch from last year shows. After this, we took a look at the Ring Nebula, M57, and Dumbell Nebula, M27. I asked my daughter whether she thought M57 looked like a donut, and she replied that it looked more like a pizza.

Over the course of the tour, the kids both amazed me with their level of comfort with the dark. My 8 year old daughter decided to re-enact something from Animal Planet as she pretended to be a cheetah, quietly stalking her stargazing prey around the perimeter of the cul-de-sac. She succeeded in getting around behind us and giving us a scare a couple times. She got brave enough that I had to stumble around and find her to remind her not to wander off into the scrub in an effort to better sneak up on us.

After checking out a number of bright open clusters, globular clusters and planetary nebulae, I decided to give something new a try--the Veil Nebula. I had viewed it before in Bill Ferris' and Max Oelschlaeger's scopes, but wasn't sure what to expect through my 6" newtonian. After nudging the scope to the appropriate spot along the eastern arm of Cygnus, I was excited to see the eastern and western arcs show up in beautiful, silky detail. I shared the view with my family before they packed up and headed home for the night. It was an unbelievably peaceful and enjoyable way to spend the evening together, and as they drove off, I felt full and happy.

Now that I was on my own, I broke out the sketch tools and dug in to some concentrated observing--

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Stephan's Quintet

I've had a goal of seeing this enticing collection of galaxies ever since I first saw it through Bill Ferris' 10" reflector. I remember thinking how faint the galaxies were through the scope at the time, and being pretty satisfied that I was able to make out all 5 of them. Over the past year, I hoped that my observing skill had improved enough to have a slim chance of seeing them in my 6" scope. I was also motivated by a sketch made by Eric Graff some time ago using an f/5 6" scope.

I had tried to find them from my front yard the week before, but that search ended in utter failure. This time I had fantastic skies to work with. I also had the precise location printed out for reference. The quintet was also in the best possible sky position, as evidenced by the fact I needed to lay on my back under the scope to sight down the edge of the tube to get in the right vicinity to use the finder. (I really need a Telrad, I know =) The galaxies would be located in the southern quadrant of a keystone-shaped asterism of stars. As I pored over this view in the eyepiece, that region of the asterism gradually revealed itself to be a bit lighter than the surrounding field, and somewhat mottled. It took a lot of searching, deep breathing, and concentration to slowly discern the faintest hints of soft light that were hovering in and out of visibility.

The first patch of light to give itself up was the southern soft oval in the sketch, NGC 7320. The next to reveal itself was a smaller, western oval of light that turned out to be the combined form of NGC7318A and NGC7318B. I made a note in my journal that this smudge seemed to split in two on a couple occasions, but not consistently enough to confirm. Finally I got the very slimmest hint of a soft smudge northeast of the first two sightings. This one was harder to pin down, but something was there, and it turned out to be NGC7319. I did not pick up on NGC 7317, but I did plot a star at its position (GSC 0274301548). If I had any chance of picking up this galaxy by itself, the 12th magnitude star apparently outshone it enough to hide it from my prying eyes. I didn't plot every star I saw, mostly enough to verify the sighting later. The faintest I plotted was GSC0274301406 with a photographic magnitude of 13.75.

This was a very tough observation--on par with the Horsehead Nebula observation, but it was really rewarding to have spotted members of this unique cluster of galaxies.

Stephan's Quintet was at the center of a debate about the validity of galactic redshifts as a means of determining distance to objects and structures in the universe. Photographic images of the galaxies clearly show some of them to be interacting gravitationally with each other, pulling tails of debris from each other. Furthermore, 4 out of 5 of the galaxies have a similar redshift of 6000 km/sec. NGC 7320, however, has a much smaller redshift of 760 km/sec. Some have pointed to debris and tails around NGC 7320 as evidence that it must be a member of the group of galaxies, so the difference in redshift couldn't be a reliable indication of distance in the universe. However, recent imaging by the Hubble Space Telescope revealed individual stars, clusters and nebulae in NGC 7320 that wasn't visible in the other galaxies, thus placing it much closer than the other galaxies, in agreement with its redshift value.

Subject: NGC7317, NGC7318A, NGC7318B, NGC7319, NGC7320 - Stephan's Quintet
Date/Time: September 30, 2005 - 10:30 PM (October 1, 2005 - 05:30 UT)
Observing Loc.: Cinder Hills Overlook, Sunset Crater Nat'l Monument, AZ
Instrument: Orion SVP 6LT Reflector (150 mm dia./1200 mm F/L)
Eyepieces/Mag.: 10 mm (120 X)
Conditions: Clear, calm, 48�F
Seeing: ~2-3/10 Pickering
Transparency: Mag 6.3 NELM (based on M33)
Sources: SEDS, Skyhound Archives, NOAO

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The Veil Nebula

After some level of success with Stephan's Quintet, I had to come back to the Veil Nebula to record the wonderful sight.

The western arc, NGC 6960, was my favorite. A brilliant yellow-orange star,52 Cygni, blazed at its heart. North of this star, the nebula condensed to a point and appeared smoothly striated. South of the star, the nebula broadened and became more mottled, as though the star was a stone breaking the surface of a swift flowing stream, throwing eddies into the downstream current. I subsequently read a report on the Skyhound site's Veil Nebula page that referred to the shape as a squid. I can clearly see that squid now, scuttling through inky water, it's great glowing orb of an eye staring back at me.

The eastern arc of the nebula, NGC 6992/5, was broader, more mottled and complex. In a way, it looked like the great curved arm of a Barrow Wight reaching, stretching to the south where its fingers curled around some unseen prize. The arm would be NGC 6992, and the hand would be NGC 6995. There appeared to be a fainter arc to the west, running roughly parallel to the southern half of the nebula as seen in the eyepiece. Some of that fainter parallel nebulosity is real--the far southern portion. But as the rollover graphic shows, I saw some mists that really aren't there a little further north. Perhaps I was catching some reflections in the eyepiece, or making more of unresolved stellar groupings than was really there. I did let the scope get into an uncomfortable viewing angle by the time I began this sketch, and didn't want to waste time repositioning it.

The Veil Nebula is part of a large nebula complex known as the Cygnus Loop that lies 1500 to 2500 light years away. These filaments of glowing gas are the result of a supernova that exploded anywhere from 5,000 to 30,000 years ago (depending on what your source is). The deceased star shone as bright as a crescent moon in the sky as it blasted its outer shells of gas into space. This expanding shockwave now covers 3� of the sky--as wide as 6 full moons. As this shockwave collides with interstellar material, it ionizes the matter and generates the beautiful glowing shell we see today.

Subject: NGC 6960, NGC 6992, NGC 6995 - The Veil Nebula
Date/Time: September 30, 2005 - 11:30 PM (October 1, 2005 - 06:30 UT)
Observing Loc.: Cinder Hills Overlook, Sunset Crater Nat'l Monument, AZ
Instrument: Orion SVP 6LT Reflector (150 mm dia./1200 mm F/L)
Eyepieces/Mag.: 32 mm + Ultrablock Filter (38 X)
Conditions: Clear, breezy
Seeing: ~2-3/10 Pickering
Transparency: Mag 6.3 NELM (based on M33)
Sources: SEDS, NGC/IC Project, NOAO

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M31, M32, and M110 -- Andromeda Galaxy and Companions

I've really been wanting to spend some time on this collection. These 3 galaxies make for a majestic view. I've been observing M31 off and on for a while now, trying to get a better sense of what it displays in my scope. M31 displayed a nearly stellar core, with brightness that fell off gently to the southeast. The northwest side dropped in sharpness quickly, giving a starting point to finding the inner dust lane. The second dust lane is much harder to discern and there is just a tinge of brightening on the other side of it. M110 really enlarged in apparent size with averted vision. M32 sat very close to the fade-off on the southeast side of M31. An orange star rested 18' north of the core of M31. There were lots of triangle asterisms peppering the field. I later made an overlay with an NOAO photograph of M31 to compare my dust lane positions. At first glance I was bummed that the outer lane in my sketch seemed placed too far away from the core. But as I compared the position of two stars I used to frame the lane, it turns out I positioned these framing stars too far away from the core of M31. You can see them immediately northwest of the core on either side of the 2nd dust lane.

I also noted that the early morning mosquitos gave my quite a surprise--they were huuuge.

Visible to the naked eye under even moderate skies, M31, The Andromeda Galaxy, was first described as the "little cloud" by the Persian astronomer Abd-al-Rahman in 964 AD. It is our nearest, large neighbor galaxy. It comes as a set with two smaller, but prominent elliptical satellite galaxies, M32 and M110. It lies about 2.9 million light years away and is approaching our galaxy at 100 km/sec. Not only does The Andromeda Galaxy occupy a large swath of sky (more than 6 times the width of the full moon), but it is literally a huge galaxy at 250,000 light years wide. That makes it more than twice the diameter of the Milky Way. Yet it appears to have less mass than our galaxy--implying that the Milky Way is much denser.

Subject: M31 (NGC 224), M32 (NGC 221), M110 (NGC 205)
Date/Time: October 1, 2005 - 3:30 AM (October 1, 2005 - 10:30 UT)
Observing Loc.: Cinder Hills Overlook, Sunset Crater Nat'l Monument, AZ
Instrument: Orion SVP 6LT Reflector (150 mm dia./1200 mm F/L)
Eyepieces/Mag.: 32 mm (38X)
Seeing: 2-3/10 Pickering
Transparency: Mag 6.3 (Based on M33)
Sources: SEDS

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NGC 1514

After observing these majestic sights, I decided to turn back to some smaller objects. The first was NGC 1514 in Taurus. This was a large, planetary nebula with a bright central star. Using the Ultrablock filter helped verify the nebula, and show it off better. The nebula was circular and centered on the main star. It seemed like there was a bright axis running northwest to southeast through the center of the disc. As I made the observation, a beautiful crescent moon was rising in the midst of a massive zodiacal light.

NGC 1514 was discovered by William Herschel in 1790. This planetary nebula caused him to reconsider his earlier assumption that these objects consisted of unresolved stars. The gas near its center is expanding outward at about 25 km/sec.

Subject: NGC 1514
Date/Time: October 1, 2005 - 4:45 AM
(October 1, 2005 - 11:45 UT)
Observing Loc.: Cinder Hills Overlook, Sunset Crater National Monument, AZ
Instrument: Orion SVP 6LT Reflector (150 mm dia./1200 mm F/L)
Eyepieces/Mag.: 10 mm (120X) + Ultrablock Filter
Conditions: Clear, calm, 45�F
Seeing: 2-3/10 Pickering
Transparency: Mag 6.3 NELM (based on M33)
Sources: SEDS, NOAO

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NGC 2392 - Eskimo Nebula/Clown Nebula

After NGC 1514, I decided to try for one more PN. What an unbelievable planetary nebula it was. NGC 2392 was very bright and detailed. It rested about 2' south-southwest of a bright star. It was circular, and had a brighter circle within. This inner circle hinted at more detail. So I bumped the magnification up from 120X to 240X, and it did very well. The central circle was mottled and perhaps roughly triangular in shape. After removing the Ultrablock filter, a central star appeared. It seemed like the star may be a bit north of center. I didn't realize this was the Eskimo Nebula until after the observation and I was double-checking a reference in the Bright Star Atlas. It's a beaty, that's for sure. I cought it just as dawn twilight was brightening in the east. It was a great way to end the night's observations.

The double-shell morphology of NGC 2392 helps contribute to it's entrancing appearance. The nebula's visual magnitude is 9.1, and it's central star, HD 59088, has a visual magnitude of 10.5. The distance is not well known, but has been estimated at 3000 light years. It was discovered by William Herschel in 1787.

Subject: NGC 2392 - The Eskima Nebula/Clown Nebula
Date/Time: October 1, 2005 - 5:15 AM (October 1, 2005 - 12:15 UT)
Observing Loc.: Cinder Hills Overlook, Sunset Crater National Monument, AZ
Instrument: Orion SVP 6LT Reflector (150 mm dia./1200 mm F/L)
Eyepieces/Mag.: 10 mm (120X), 10 mm + 2X Barlow (240X) + Ultrablock
Conditions: Clear, calm, 48�F
Seeing: 2-3/10 Pickering
Transparency: Mag 5.2 NELM (based on Ursa Minor)
Sources: SEDS,NOAO

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Over the course of the night, I couldn't help but stop and take in the serene beauty around me. Mars spent the better part of the night in good company with the Pleiades, Hyades, and Orion. The collection was too a bit too much for me to resist.

The sky glow at the horizon had a distinct blue-green color to it--whether this was a complimentary afterimage to the red of my light, or a real perception, it was exotic. Around 2AM, an owl began hooting somewhere to the east, and continued to check in with me every once and a while until dawn. At one point while snagging pictures of the surroundisg, I noticed a pulsating point of light moving west to east toward Ursa Major. It didn't seem to be a plane, since the light pulsed gradually in and out of peak brightness rather than flashing. I turned the camera on it for a 30 second exposure.

In the hours before dawn, I kept getting the impression that dawn was breaking earlier than I knew it could be. It finally occurred to me that the zodiacal light was rising as a massive cone in the east, and reaching all the way up to the Orion Arm of the Milky Way.

During the course of my planetary nebula observations, the moon delivered a haunting spectacle as it rose from the conical base of the zodiacal light.

As things brightened up too much for DSO observations, I took some time to observe the fantastic rings of Saturn while the rising sun painted the horizon orange and yellow.

I finished the night by polishing off some observation notes, and photographing the majestic sunrise against the cool, silent might of the surrounding volcanic field.

As much as I appreciate the short observing sessions in my front yard, nights likes this remind me how embracing and wonderful amateur astronomy can be.