Monday, July 31, 2000

Reflections - Too Many Galaxies: The Way It Should Be

Time to sink in, and a way to measure, reflection. These are things a dark sky trip needs to gain perspective. Many times, while the experience is occurring, it is either amazing and so exciting that the senses are overwhelmed and one is incapable of fully appreciating it, or if a regular annual occurrence, one can be jaded and suffer let down by idealizing prior experience. The latter has been my problem at Mt. Lassen over the past few years. After seven years of going, the sky up there is an expectation, not a surprise. It somehow seems less than I remember. Yes, I hear the exclamations and excitement of others, but after enough times, even that does not surprise, or excite.

So it was not until weeks, or a month or so had gone by, and after a few nights observing near the lights of 6 million other San Francisco area residents that I could again begin to assess how unique and worthy an experience a trip to a real dark sky is. This year like last our first trip to Mt. Lassen was the better of two. However, that does not mean the later trip this year was a waste. Beside the sky, which even in poor conditions beats anything we usually get back home, a lot of other factors join in shaping the experience. Trips to McArthur-Burney Falls where the waters fall from a rock face like pieces of The Veil Nebula, the cool aqua blue of the pool below. The beauty of Chaos Craggs reflecting near perfect images in Manzanita Lake. Kids around the campfire, lots of kids belonging to other amateur astronomers, and the sounds of their laughter building lifetime memories. A towrering 32" telescope and four or five of us lifting the mirror into its cell. Friends coming and going... meals together, knowing that people 6,000 feet below are sweltered at 112 degrees while we enjoy the cooler mountain air. Driving to Bumpass Hell over Lassen Pass with the 10,500 foot Peak above us and dacite lava fields on all sides, then beginning to descend into the maw of ancient Mt. Tehama's giant caldera. To our west, the northernmost portion of California's great central valley lay wide and flat, giving way to the coastal mountains beyond hiding the wild beaches and small towns between San Francisco and Oregon. Setting up at Bumpass Hell, it is impossible to not notice the huge lava plugs erupting in frozen magnificence, straining to be free of Lassen Peak. They remind me of Michaelangelo's bound slaves. The memories from these trips are innumerable.

Even in lesser skies then had been hoped for, there was some very good observing! I specifically recall our second night during the second trip. I had resolved to get back on my observing program, and see how much of Bootes I could finish before the constellation dipped below the horizon and disappeared for another season.

I like to observe with friends. Ken Head was set up next to me, and we'd locate and confirm objects together.

We began with NCG 7530, a galaxy that lies between Nekkar (42-Beta Bootis), Bootes' tiny head, and 19-Lambda Bootis which is the bend in his left arm. Two dimmer stars pin down the location, mag 5.7 SAO 45190 and 3 degrees north its twin at mag 5.7 SAO 45145, which lies southerly in a line of naked-eye stars that stretch up, between the bent upper arm of Bootes and Nekkar. This star is very near the position of NGC 7530. By centering this star, mag 6.6 SAO 45133 can be found and used to determine direction to the galaxy. There are several in-eyepiece asterisms that mark the correct location. The nearest, but among the dimmest, are four stars about 12' NNE, forming a Mercedes hood ornament. In the field with NGC 5730 is NGC 5731. Both were seen this evening, easy to view at mags 14.1 and 13.1 visual. Both are about the same size, at 1.6 x 0.4 ... nice slits of light appearing 4 minutes apart, so deceiving!

Next up to NGC 5735, nicely situated along Bootes beltline, just south of the midpoint between the famous double star Izar on his western hip, and eastern star in his belt clasp, 28-Sigma Bootis. Nice when the stars are close by! This galaxy is about 2.5'x 1.8' and is easy to see. Of course, in Lassen's skies, even when not a particularly outstanding night, lots of things are easy to see. About 5' east we observed the small galaxy CGCG6164-14, which at mag 15.7 would be a good find, but with only .5'x.4' of surface area, the magnitude is deceiving, since the surface brightness is something probably in the mid 14's or brighter. If you can get deep, into the 15's, there are actually a nice chains of galaxies on a E/W sweep, one more widespread involving NGC 5735, and another chain to its north. Worth a visit.

The next object was one that I found intriguing. On a line about one forth the distance between mag 4.0 23-Theta Bootis (the top of Bootes left arm) and mag 3.3 12-Iota Draconis (Edasich, the brightest star in the arch of Draco's body) sits NGC 5751, a nice mag 13 spiral galaxy, elongated 2x1 NE/SW at 1.5'x0.8'. A mag 7 star sits nearly north, 24' away, and opposite the galaxy a distinctive cornucopia of stars spreads away from it in a southeasterly cant. The swath of stars extends about 28' and opens to about 16' width. This is a very pretty field of view. However, while Ken was confirming this object I moved 24' due west from 5751 to a bright star, then followed a small curve of stars northward. Pumping up the power to about 280X, I was able to see MK477, a galaxy in a tiny speck. At mag 15.4 or so, with an angular apparent surface area of 0.4'x0.3', it is nearly stellar upon first glimpse. Without additional magnification it would be quite elusive. Reading about this galaxy after the fact, I learned that it is has strong OIII lines. Ever wonder if such a filter would enhance the view of a galaxy? As far as the eyepiece view goes, the galaxy appeared to be the third and southern most "star" in a chain of three, and it nearly bisected a mag 12 and mag 13 star... this type if just fun to find.

Following this find, we went on to log NGC 5754, between Seginus (Gamma Bootis) and Nekkar. This is a fun find due to the closeness of NGC 5755 and NGC 5753. All three are within about 4' of each other, and ranging in magnitude from 13.8 to 15.8.

NGC 5787 is a round galaxy just north of Nekkar. If you use a Telrad, it is an easy find, with the Telrad just touching the outer ring of the finder. You can place this galaxy and four others in the same field of view (48' field in my scope, with a 20 Nagler). NGC 5784, UGCs 9585 and 9583 and CGCG 221-10 showed, but I missed MCG-31-4. Helping locate this group, a pair stars about mag 8.5 lie about 6' apart and 20' north.

NGC 5789 is a mag 13.5 galaxy, just under 1'x1' in size, between Izar and 49 Delta-Bootis (the shepherd's right shoulder). A nice chain of stars with several bright members sits SW of the galaxy, extending about 40' in length. Logged with this galaxy were NGC 5798, UGC 9588 and UGC 9597, ranging in magnitude form mid 13 to high 15.

Finally, the find of the night.

Sometimes, it takes patience to get a great view. It is the thing I suppose that keeps people working lists containing unexciting smudges over months and years. While some would consider this path a boring endeavor, there is no arguing with that the experience pays when something good comes along.

We turned our scopes toward NGC 5875. This galaxy sits between Nekkar (Bootes' head) and Edasich (12 Iota-Draconis), about 2/3rds toward the latter. It is in the middle of nowhere. NGC 5875 has a bright mag 7.3 star (SAO 97410) 24' NW, and a chain of three distinctive stars leading in descending magnitude toward the galaxy SW beginning with the furthest and brightest star about 10' distant. Once you have located NGC 5875, look 6' SW and find two mag 15 galaxies, CGCG274-26 and MK846. Continue in the same field of view another 6' and find mag 14.3 UGC 9741 and MCG 9-25-25 at mag 15.3. Now, head about 16' north toward the aforementioned SAO 97410 to find CGCG274-19 shimmering at mag 15. What a field! But that's not all. Around 18' east of NGC 5875, two other mag 15 galaxies will float into view. These are MCG 9-25-31 and CGCG 274-32.

I spent quite a bit of time looking at this field. I don't know if too many photos can cause eye fatigue, but after this view, I spent time visiting with other observers at the star party. Time flew by. Looking up again, I found I could log maybe one or two more objects in Bootes, but it was dropping quickly. A few more views with multiple galaxies, and it was done.

We spent a while playing in Cepheus, and just cruising around in the Cygnus Milky Way. The views were simply spectacular. Barnard objects were dark holes in rich Milky Way fields. Stars showed colors more vibrantly than I am unaccustomed to. Clusters, asterisms, bits and pieces of creation strewn throughout unexpected places that the eyepiece just happened upon. If only we had skies like this back home!

Eventually the night was done. My once jaded soul was filled with new fuel and my desire for more observing had been rekindled. It was more than enough to let me again know the difference, and feeling I was not exaggerating when asked a months or so prior to the trip how Lassen's skies compared to our regular haunts. I had thought for a moment and said "there is no comparison."

I can look forward again, waiting for better skies, shared views, friends out together under skies that show too many galaxies! The way it should be.

We drove back to camp and sat for a while, sipping cold drinks, talking about the night, friends, whatever came to mind in the hours before dawn. There, seated on a small picnic table, spinning through space for a few blinks of the eye, our tiny piece of infinity. Sometimes, looking out through my telescope, I have the strange sensation of time and distance, and the view loses its two dimensional illusion. I feel the immensity, or really, realize it in the very crude way most humans are capable of. I think of Carl Sagan's "Reflections on a Mote of Dust" ( in part:

We succeeded in taking that picture [from deep space], and, if you look at it, you see a dot. That's here. That's home. That's us. On it, everyone you ever heard of, every human being who ever lived, lived out their lives. The aggregate of all our joys and sufferings, thousands of confident religions, ideologies and economic doctrines, every hunter and forager, every hero and coward, every creator and destroyer of civilizations, every king and peasant, every young couple in love, every hopeful child, every mother and father, every inventor and explorer, every teacher of morals, every corrupt politician, every superstar, every supreme leader, every saint and sinner in the history of our species, lived there on a mote of dust, suspended in a sunbeam.

It was a great trip. In a wider sense, what a great trip it has been!

It just takes some time to sink in.

ps - Telescope was an 18" f/4.5 Obsession, with a 20mm Type II Nagler unless otherwise noted.

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