Saturday, May 31, 2003

Edges

I had a great time at Michelle Stone's Plettstone Astronomy Preserve Saturday night. Getting there was a nice drive over Pacheco Pass then along the backroads up highways 33 to 140, through Merced, emerging the other side of the cowtown with the view of the Sierra foothills putting a smile on my face. I was heading to Mariposa, Spanish for butterfly - and certainly the place has all the beauty one enjoys witnessing the happy flight of this small wonder of nature. I always feel renewed when I see those mountains, like emerging from the chrysallis - it is a different world once the city is behind. Two and a half hours - a nice short drive, and my soul begins again to gain the edge. If the scenery isn't enough to make the drive worthwhile, the promise of dark skies in the most welcoming observing setting I know is, by a long shot.

I was the last to arrive. Michelle and Paul were there already, happy to have astro-company at their property. I pulled in to find Rashad grinning - ear to ear - standing next to his new 16" platform driven Dob. What a sight. Guillermo's gear was set up and Richard was pulling equipment out of his pickup. I had not brought a scope - as I had purchased Michelle's 18" Obsession which I would bring home to my daughter, Mimi. Mimi and I had been having a fun little "argument" about observing, she, always pushing to get her hands on my 18" Obsession, telling me I could use the 10". So, we solved the problem. Certainly, with her 15 year old eyes and experience star hopping, Mimi will have the edge over me. Maybe I need a bigger scope!

As twilight darkened, I began observing. Seeing was soft, but even before dark, maybe halfway between sunset and the end of astronomical twilight, I began popping galaxies in Virgo. That was my target of the night - I have Virgo, Canis Venatici and Coma Berenices left (parts of them) on my big Herschel project. Seems like poor spring weather every year prolongs this project. But there is no rush - the stars aren't going anywhere - and I have long ago given up on search and destroy astronomy. Now, I find something, take some time looking at it, change eyepieces, call over friends, etc. It is supposed to be relaxing, rather than feeling like I'm participating in the Indy 500.

Some of Michelle's neighbors stopped by, a young couple, early 20's. They asked lots of questions, looked through Mimi's scope, spent about an hour. It has been a long time since I'd played tour guide. It is still enjoyable. These two loved the term "spaghettification" when I talked about crossing an event horizon. Fun stuff. It is always rewarding to see people begin to understand what they see, when they look at the night sky. Few people realize just how "local" our view of the universe is. I think it was a revelation when they learned the stars we see are part of our arm of our galaxy, and the "Milky Way" we see rising in the east is another arm - but 20,000 light years away.

Well, the night when along wonderfully. I was landing on object after object in Virgo. It was as if I had somehow had a "GoTo" implant - it was too easy. I have to say, having all those dim stars visible to hop off of does give one an edge.

I logged between 35 and 40 new objects. Some fields, as one would expect in Virgo, contained multiple galaxies. These were fun to take my time on, and see just what I could tease out - just how faint I could pick up. Steadier seeing would have helped, some galaxies were such small round little smudges, when the seeing would be at its softest, it would be difficult to tell what was what. But when things steadied up, it was marvelous.

My favorite view of the night was the field around NGC 4168. At mag 11.2 with a surface brightness about 13, this galaxy was a beacon. Nice size too, at 2.8' x 2.3'. NGCs 4164 and 4165 were right there with it. Several IC galaxies dotted the periphery of the field. To the east and northeast I could see NGCs 4193 and 4189, bright stuff. Fun stuff.

I was at the computer, verifying objects, and took a little to long - when I returned the view had drifted east. Look at that! It was a huge edge-on galaxy smack in the center of the FOV. What was that to its SW, close by? Another edge-on. What a view. Wait... uh.... to the northeast of the first one.... really? Another dimmer edge on! Three in a row! I could hardly believe it. This was the most rewarding view of the night. I called friends over for a peek. It was hard to believe. If you have a chance, look for NGC 4216 and see its two dimmer companions, NGC 4206 and 4222. There are many other dim galaxies in the same field that, under the right conditions, will turn the view into a veritable candy store of deep sky observing.

But that view, of the three edge-ons, that was amazing. That, to me, is the view that had the edge on all others.

Sunday, May 4, 2003

If Not For Dew...

I had my 10" f/5.7 CPT Dob out back tonight. First clear night in a long time. Sure looked good, but even early on it was obvious that things could get wet.

Before going out I went to the limiting magnitude page at:

http://www.namnmeteors.org/lm_calc.html

and filled it in for 9:30 p.m.

It returned the familiar triangle of Alpha and Gamma Bootis, and Alpha Coronae Borealis, along with Alpha Canum Venaticorum, Epsilon and Eta Ursa Maoris, and a third triangle (?) of Alpha, Beta, Gamma and Delta Leonis.

I waited a while and looked at M3, which was very pleasing at 72X and 121X. It broke up nicely at the higher power.

I then looked in the NSOG for targets in the triangle areas, and decided to work Leo since it was furthest west.

NGC 2903 was very good at 72X, easy to find. At 121X it was elongated with a bright core. At 207X the stellar core was popping out and there was an halo surrounding it that seemed slightly offset to the east. The elongation of the arms was to the north and south.

Unfortunately, this would be my only success for the night. I tried for NGC 2916, but only found the nice double star 6 Leonis, shining blue and gold.

I hunted for a few other targets through a dewed Telrad, and when I found my 9x60 finder useless, I called it a night.

As amazing as it sounds, I had counts of 38, 16 and 31 stars, respectively in the triangles. This is from my Los Gatos backyard. According to the calculator on the above referenced page, that give 6.83, 6.80 and 7.02.

Next time I'll chart the star positions to confirm. There were many stars that appeared repeatedly with averted vision.

If not for dew, it could have been a great night out back.