Friday, May 18, 2001

The Home Of The Bear

Friday afternoon my daughter Mimi and I headed for Bear Valley, a small community in California's historical gold rush section of the Sierra Nevada foothills. The closest town of even modest size (meaning, there is at least on traffic light) is Mariposa. Our destination was Michelle Stone's Plettstone astronomy and nature reserve. Our drive was easy and mostly uneventful, except for missing the turnoff to highway 59 north and ending up driving through true California Central Valley backroads, an experience that was both fun and quite unexpected... this state has some amazing roads and curious sights!

Upon arriving we found two observers sitting in the shade of an old oak, sipping beers and sampling chips and salsa. Overhead was an enormous afternoon cumulus formation that we all kept eyeing with a bit of worry. After unpacking my 18" and 8" scopes, the cloud was obviously dissipating. The two observers, Peter and Guilllermo, had 20" and 18" Dobs. Michelle pulled in and opened up her observatory to let it cool down. Later we would be joined by Jim and his 15" Dob.

As evening turned to dark, Mimi decided this would be my night to observe, and she would take her turn on Saturday. This was a good arrangement as far as I was concerned... if I was tired the next night I could take it easy while she used the scopes.

Friday night observing...

As dark set in I looked to Ursa Major. This is one of the many spring time constellations I have remaining on the Herschel list. Spring for me consists of Virgo, Ursa Major, Canes Venatici, Coma Berenices. Perhaps the richest galaxy portion of the sky. It would be only appropriate this trip that, just up the road from Bear Valley, that I spend my time in the home of the bear.

I began with NGC 3795. If the bowl of the Big Dipper were filled with liquid and NGC 3795 floated on top, you'd find it nearly dead-center. It is an easy location just below the rim of the pot. Bright and elongated, this galaxy is a snap in large aperture. It is easy to see the 2.0'x0.5' elonagation running NE/SW. Mag 13.1 and surface brightness (SB) 13.1. Nice sight!

Next was NGC 3971. Located in the SW corner of the of the bear's domain, this galaxy is found by using mag 3.5 Alula Borealis and Gamma Comae Berenices to make a line. The galaxy is nearly at the half-way point. Round and bright at mag 12.7 and SB 13.1, this is an easy target. Helping confirm the find is a straight chain of 3 dim stars just south of the fuzzy spot, pointing right at it just a few arc minutes away.

NGC 4149 was fairly small and very thin. This helped increase its SB to 11.8 from its mag of 13.2. Not particularly dim, but small and fairly bright. There are several notable bright stars in the field, providing plenty of stars with which to confirm the correct location. If you have an optical finder on your scope, this one is an easy star hop off Megrez, the star that connects the handle of the Dipper to the bowl.

NGC 4566 seems to me to be a lonely place. To the eye of the amateur astronomer at a moderately sized telescope, the galaxy sits alone in a relatively poor field of dim stars. This is typical of many Herschel galaxies, rather non-descript, round, a bit of a brighter core, but nothing really outstanding. If they were all like this, the universe could be a boring place (visually). At least the hunt was fun... it is located under the handle of the Dipper, just over 3 degrees SW of Alioth.

Just tick back toward Alioth was my next target, NGC 4646. Just as the prior galaxy seemed to be in a sparse section of the cosmos, so did this one. Other dimmer galaxies were present, but my eyes "wanted" to see them more than I think I actually did perceive them. 4646 was nearly SE of a dim chain of four or so stars, and there even seemed to be a star almost embedded over the small glowing puff. Once you've found this one, it is pretty easy to see. Its dimensions of 0.6'x0.3' give its mag 13.4 a substantially higher SB of 11.4.

Where the prior two galaxies were loney, NGC 5007 was fun to see. It is in a busy field of other galaxies! Using Alioth and Alcor in the Dipper's handle, I drew a line "up" from Alioth to a close pair of dimmer stars half-way to Kappa-Draconis, which is a naked eye multiple star. Back to Alcor, I split the distance again to Kappa and used the prior two dimmer doubles as a landmark. The halfway point from Alcor put me very close to the galaxy. In the field I could easily pick out, at 0.9'x0.6' its mag 13.3 had an SB in the mid 12's. Something about it reminding me of the Merope Nebula, as did the view of two other galaxies WNW of a bright star in the field. The other galaxies, UGC 8234 and UGC 8237 were also easy "wispy" targets about the same size and shape, but dimmer, than 5007. Further to the west of the bright star but still in the field was UGC 8214, dimmer still, but obvious, a round small puff. Next was a challenge, to see MCG10-19-44 at mag 15.7 just about in the same position as NGC 5007. It helped to look thought Peter's 20" to find the location, but once I had seen it there, I coud see it in the 18. Another challenge galaxy lay directly opposite the first two UGC's from the bright star. MCG10-19-37 was also pretty obvious, even though it was in the mid 15's its small 0.5' size gave it some "shine"... This had been a wonderful field.

To our east and south the Milky Way was now rising, reminding me of how the sky used to seem to me at Fremont Peak many years ago. Clouds of stars. As it rose, the area around Deneb took on that famous sugary appearance that dark clear skies reveal. The star clouds around Scutum and Sagittarius was too dense to show detail, other than the clearly defined dark areas around in weaving trough. Same can be said for the dark lanes in through the Cygnus Rift and star cloud. Fantistic. But in a way, sad too. The sky here is so much better than back home. This reminded me of a poem Mimi showed me just a day before:

Somebody Has To

Somebody has to go polish the stars,
They're looking a little bit dull.
Somebody has to go polish the stars,
For the eagles and starlings and gulls
Have all been complaining they're tarnished and worn,
They say they want new ones we cannot afford.
So please get your rags
And your polishing jars,
Somebody has to go polish the stars.

I don't know where she found it. The author is Shel Siverstein.

Thank goodness for people like Michelle Stone, Albert Highe, the folks up at Fiddletown. These patrons of amateur astronomy allow interested amateur astronomers access in safe and secure locations just a few hours from home, where we see what we miss at our other nearby observing sites. The little bit of extra effort to get to these places is small when compared to the views we are rewarded with.

Back to observing.

I was next off to NGC 5216. It is located close to the same set of finder stars I used for NGC 5007, so this was relatively easy to find. I went off Alcor and headed almost due north to a chain of 3 naked eye stars in Draco. The dimmest is the furthest west. Using that star, I found another dim naked eye star halfway back to Alcor. NGC 5216 is right between these two dim naked eye stars. A dim necklace of stars are about 10' to the east of the galaxy. It is a very attractive setting. The galaxy is part of a grouping known as Keenan's System, and Arp 104. This is a rather oblate round galaxy, 2.5'x1.5' N/S in direction. To its north is NGC 5218, just a bit smaller roundish oblate galaxy laying E/W. NGC 5205 was at the edge of my field of view to the SW, and was larger and dimmer than the other two objects. The two close galaxies and nice star field made this system memorable.

NGC 5250 is easy to find near the end of the Big Bear's tail. It is a round galaxy, about 1'x1', and relatively bright. A bright star sits just to its NE and there are several bright pairs throughout the field.

Again just off the tip of the Bear's tail, NGC 5256 hangs between Alkaid and M51 in Canes Venatici. This is a small area, so the galaxy was easy to locate. The field is filled with notable star pairs. One tight pair is just 6' west of the galaxy, and easy to identify. This galaxy is also known as Markarian 266, and listed a peculiar. The DSS image does not show much extraordinary, but visually, it seemed to have a very bright core which took up most of the visible portion of the object. A thin halo was barely noticeable.

By now I was wearing down. I walked over to look through Michelle's pier mounted refractor, and we put in the "Kings Table" or NGC 6231 in the lower section of Scorpius' tail. What a show! There was so much unsteadiness down low that you could nearly get seasick looking at this jewelbox swimming all over the place. Individual stars pulsed forward then back, in the most uncoordinated display of atmospheric jitterbugging I've ever seen. Weird, but fun!

I returned to my scope to finish up.

NGC 5368 is a round galaxy very close to NGC 5216. This is a small spiral galaxy with a pretty high surface brightness at 12.4. A nice zig-zag of stars ran at it from the north, while several pair of stars sat nearby to the south. The galaxy showed at most hints of detail, but it was small, and the sky was now dancing.

When I first tried for NGC 5379 I mistakenly stumbled onto M101. 101 was awesome in detail, HII regions popping out all over the giant galaxy's spiral structure. But that was not my quarry. 5379 is a nice lenticular galaxy about 2.2'x1.0', and fairly bright with a SB of 13.5. In the field it ran mostly E/W, and had another galaxy, NGC 5389, just a few arcminutes to its E. 5389 is almost twice the length as 5379, but still just 1.0' along it minor axis, yet appeared nearly as bright. Half a field to the SSW was NGC 5376, again with a SB of 13. This is an attractive field that includes a nice slow arc of stars to the east of the galaxies.

Appropriately, just as I was calling it a night, the Big Bear was heading down into the valley, and my target, NGC 5486, was trailing his tail, being swept along by Bootes the Herdsman, for nearly straggling into his domain. This was also a wonderful field. NGC 5486 was almost 2'x1' and lay nearly E/W. Just to its south was NGC 5485 at 2.3'x1.9' and significantly brighter and more obvious. A wide pair of bright stars were landmarks to identifying this field, being in the high 7's and 8's. Between them and the galaxies sat a dim little triangle of stars. This somehow reminded me of a different type of Gemini configuration, with the stars being Castor and Pollux, and the galaxies stringing down along the bodies.

Mimi had been sleeping for a while now. A few of the other observers had gone to bed. It was warm and clear. The sweet smell of fresh mountain air provided my good night. Mimi's turn in the Home Of The Bear was just hours away.

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