Observing Report for April 25-27, 2003. Yes, it was clear

by Albert Highe

Observing Report April 25, 26, 27, 2003 - Sedona, AZ

During the past month, I've been researching some more galaxy clusters and preparing observing lists and finder charts for them. Along with everyone else, I was greatly disappointed to see the rainy weather forecasted for this New Moon period. I was determined not to let all my hard work go to waste.

Fortunately, Denny W. once again graciously invited me to visit him in the dark skies of Sedona, AZ. A friend of mine, Isaac, and I drove down Thursday. When we arrived, the skies were clear and dark.

Sedona is one of those rare communities where there are no streetlights, ordinances require shielded lighting, and bright porch lights are illegal. The view from Denny's driveway rivals the best dark skies I've ever seen. However, we didn't set up there because of passing cars. Instead, we drove 10 minutes to a housing development in progress. We set up at the end of a cul-de-sac, away from the main road. During set-up, we enjoyed the view of one of Sedona's typical attractions ( http://pw2.netcom.com/~ahighe/CathedralRockSite.jpg). For $680,000 you can buy the 1 acre lot that backs up to national forest and has this view out the rear window.

The weather each night was outstanding. The afternoon wind subsided around sunset, leaving us with rather mild, dry, and calm conditions. Temperatures dropped from the low-80's during the day to the mid-60's at sunset. Thereafter, the temperature dropped slowly and steadily throughout the night, reaching the high-40's at 4AM. The relative humidity never got above 50%. Seeing was best Friday and Saturday, permitting excellent views of the planets at 400X. Transparency was good. Seeing was a bit softer on Sunday, but the transparency improved to very good. The conditions allowed outstanding views of bright favorites in addition to locating extremely faint fuzzies, encouraging us to observe until 4AM almost every night.

I used my 17.5" f/4.5 ultralight with 14mm Radian, 9mm and 7mm Nagler T6's, and 5mm Takahashi LE.

Each night I started out viewing the planets and showing some bright Messiers to a few local amateurs. After they left, I settled down to observe Abell galaxy clusters and selected faint fuzzies. Later, I switched back to observing bright favorites.

Selected Highlights

I had prepared finder charts for three more Abell galaxy clusters. I haven't yet finished my research and write-ups. However, at least the labeled finder charts for the central 1 X 1 area for each can be found at the following links.

Abell 2199 http://pw2.netcom.com/~ahighe/a2199temp.htm

Abell 2151 http://pw2.netcom.com/~ahighe/a2151temp.htm

Abell 1656 http://pw2.netcom.com/~ahighe/a1656.htm

Using the finder charts, I logged 53 objects in A2199 and 12 objects in A2151.

Abell 1656, the Coma Cluster, is by far the richest and most dense galaxy cluster. I only made a small dent observing its members. I decided to begin my search by identifying those galaxies in the dense center. Working only the central 0.4 X 0.4, I identified 38 of the brighter members. With members stretching as far as 5, I've got hundreds more to find!

In addition, I logged 16 new objects in Abell 1367 ( http://pw2.netcom.com/~ahighe/a1367.html), bringing the total to 93. Four are likely not cluster members.

Another highlight was a group of four galaxies in Coma Berenices known as "The Box". These four galaxies lie at the corners of a square whose diagonal is less than 4'. The square is rotated approximately 45 from North. Observations are with a 7mm Nagler T6 (286X).

NGC 4169 (mag 12.2, 1.8' x 0.9') The brightest in the group, lying at the West corner. Bright oval with large brighter central area. Visible with direct vision.

NGC 4174 (13.4, 0.6' x 0.3') Going clockwise around the box, this galaxy lies at the southern corner. It appeared to be the third brightest, although it has a bright stellar core that makes it sometimes appear to be the second brightest. Small and slightly elongated. Brighter portions visible with direct vision.

NGC 4175 (13.3, 1.8' x 0.4') Overall, second brightest and lying at the east corner. Size intermediate between above two. Somewhat elongated. Visible with direct vision.

NGC 4173 (13.0, 5.0' x 0.7') Lies at the north end of the box. Considerably fainter than the above three. At first glance, it wasn't visible. My eyes were drawn to the brighter three. With averted vision, it appears as a long, uniform, low-surface brightness smear. The SE corner appears truncated. It looked to me like a faint Bunsen burner flame.

Scanning the neighborhood, I found a nice line of three galaxies 3/4 to the west. They are approximately equally spaced across 10', nearly spanning the f.o.v. in the 7mm Nagler (286X).

NGC 4131 (13.3, 1.3' x 0.7')
NGC 4132 (14.0, 1.1' x 0.4')
NGC 4134 (12.8, 2.2' x 0.9')

They all appear oval with approximately the same brightness. There was also another galaxy in this same f.o.v.

MCG+5-29-24 (15.8, 0.9' x 0.2') Very small and faint. Glimpsed with averted vision approximately 2' NE of NGC 4132.

While in Coma, I also stopped at NGC 4565 (9.6, 15.8' x 2.1') At 286X with the 7mm Nagler, this galaxy was stunning. The bright shaft bisected the f.o.v., its pointed tips piercing the walls of the eyepiece. The bright central region looked like a flattened dome. The base of the dome, defined by the fairly wide dust lane, sat below the central line of the galaxy. On the other side of the dust lane, the outer reaches of the central bulge was visible as a faint glow. A bright star or stellar core was visible at the center of the dome. Extending from the dome in both directions were thin needles of light. When sweeping the area, I could trace them out beyond the f.o.v.

There were other highlights, like visiting the showpiece objects in Sagittarius. Describing wondrous views of the Swan, M22, etc., would take too long. Let me just say that it was a grand time, well worth the 13 hour drive.

Many thanks to Denny for being such a wonderful host.