Dinosaur Point

by Albert Highe

Last night was one of those rare awesome observing sessions. What can I say except that you should've been there.

During the day, satellite images showed clouds skirting the Bay Area to the north. Observing would be a gamble, depending on the strength and direction of wind. The Clear Sky Clock predicted clear skies, but poor transparency.

At Noon I was optimistic. The skies in Redwood City and southward were completely clear, but I could see clouds to the north. As I left the house at 1:30PM, the radio said that clouds had already covered San Francisco. As I drove south, toward Dinosaur Point, in my rear view mirror I could see some thin clouds behind me in the distance. The question going through my mind was "How long would it take for them to catch up to us at Dino?"

By sunset, I had my answer. Clouds had crested Pacheco ridge, illuminated a brilliant red. By 5:30PM, those clouds were encroaching on Dino. It looked like it might be a short night. At least 15 scopes were set up and most everyone was milling around talking. The temperature was 46°F with a relative humidity of 61%. Through the thin cloud cover, I experimented with a couple of new (used Astromart purchases) eyepieces that arrived this week. Despite the clouds, seeing was actually quite good. The double-double was very well split with my Takahashi LE 5mm (317X) and 7.5mm (212X) eyepieces. Saturn, still low in the east, was quite good.

By 6:30PM, a large hole opened up, uncovering most of the sky. The parking lot grew quiet as everyone returned to his scope to take advantage of the clearing skies. Seeing and transparency were excellent. I judged this by observing a number of faint galaxies. I started with the Perseus Supercluster (Abell 426). Normally I start off using my 14mm Radian (113X) to view faint galaxies and then jump up to my 9mm Nagler (176X) to improve contrast. Rarely has higher magnification produced better views. However, last night, I had some of the best views ever (in my scope) of these faint galaxies using the 7.5mm LE. For example, I saw IC1907 (15.2) and UGC2665 (15.0), just north of NGC1273, which lies at the northwest corner of the parallelogram of brighter galaxies, for the first time. At the northeast corner of the parallelogram lies NGC1278. It forms a close pair (less than 1' separation) with NGC1277. At 113X, I only see one galaxy. At 176X, I have split these two. However, last night at 212X, the split was the easiest I've ever seen. And the contrast was the best I've ever seen at this magnification. Likewise, west of NGC1270, which lies outside of the parallelogram, is a close pair NGC1267 (14.1) and NGC1268 (14.2) with a separation of just over 1'. It was so obvious that when Jamie D. looked in the eyepiece, he saw them right away, without any hints what to look for. I also thought I could detect CGCG540-89 (15.8) just west of that pair.

Southeast of the parallelogram lies NGC1282 (13.7). I was also able to see nearby NGC1283 (15.0) and UGC2673 (14.6) for the first time. I could hold both with averted vision. Although fainter, NGC1283 is smaller and somewhat easier to see. UCG2673 was a bit more of a challenge because it is about the size of NGC1282.

With this success, I decided to take a look at Stephan's Quintet and other faint galaxies in the neighborhood of the edge-on galaxy NGC7331, using the 7.5mm LE. I could see quite a bit of mottling in the elongated, brighter core of NGC7331. Just east of NGC7331 is an equilateral triangle of small faint galaxies: NGC7335 (14.5), NGC7337 (15.2), NGC7340 (14.7). I could almost hold these with direct vision. Each brightened nicely with averted vision.

Stephan's Quintet lies approximately 1/2° south of NGC7331. Only at Lassen have I had a better view. The brighter four were quite easy to see with averted vision. At 212X, I could split the close pair, NGC7318A&B, about 75% of the time with averted vision.

Using The Sky software, I looked around this vicinity for other faint galaxies. Lying 1/2° northwest is NGC7315 (13.5). It was quite easy to see as an almost circular diffuse glow. I could also detect a very small dim galaxy right next to it. The Sky indicated that this was KAZ296 (15.4). Now, that's a galaxy designation I hadn't seen before.

Since I was seeing such faint and obscure (at least to me) galaxies with such relative ease, I decided to try out something else in the neighborhood. Approximately 1° north of NGC7331 I noticed a small cluster of galaxies. The brightest is UGC12127 (14.4), and that is all I expected to see. With averted vision, it appeared as a moderate size distinct oval with uniform surface brightness. What surprised me is that I also could see three small, faint galaxies encircling it. The Sky identified these as MCG6-49-61 (15.6), NCG6-49-56 (15.9), and NCG6-49-60 (15.0), all lying within 1-3' of UGC12127. Within 13' of UGC12127, I also picked up NGC7342 (14.8) and NGC7345 (15.2).

All of this in a 12.5" within a 1-1/2 hour drive from home! I was excited.

By 9:30PM the temperature had dropped below 40° with a RH in the low 70's. I have to add, that there was no wind, no dew, just great observing conditions. Occasionally, during the night, thin bands of clouds would pass through briefly. However, there was always some large open section of sky.

It was time to take a look at the planets. I bumped up the magnification to 317X with the 5mm LE. Great seeing! On Saturn, the Cassini division was a wide dark unbroken gap completely around the rings. The Crepe ring was bright and easy. The yellow-brown band on the planet face very distinct and I could see variations in its intensity. I could easily see four of the brightest moons of Saturn: Titan, mag 8.4, 1.5' south; Rhea, mag 9.8, 44" north; Dione, mag 10.2, 58" west; Tethys, mag 10.3, 47" east. In addition, Enceladus, mag 11.8, 39" east, would pop in and out of view, depending on the seeing conditions.

Jupiter was fantastic as well. I spent long minutes just gasping when conditions would steady. It was like looking at a photograph. I could clearly see each of the four main moons as different sized disks. The pale GRS had a well-defined, slightly darker border around it. The GRS itself wasn't uniform. I could detect a swirling pattern. There was a small white spot adjacent to the trailing edge of the GRS. Within other bands, I could see festoons and brown barges clearly. It's been a long time since the planets looked so good. I would return to them and share views throughout the night.

I spent the next couple of hours observing bright Messiers and other familiar favorites with different magnifications. The stars in the Trapezium were tight and gorgeous. The E and F stars were drop-dead easy.

I finished off the night by finding quite a few objects on page 19 of Sky Atlas 2000 below -25°. One highlight was a nice pairing of small open cluster and moderately-sized planetary. NGC2452, the planetary, and NGC2453, the open cluster, are separated by 8'. The open cluster is small, 5', but consists of numerous moderately-bright stars. The planetary is easy, being fairly bright (13.0) and having a diameter of 18". Normally, I wouldn't have expected the view of this pair to be very good since they lie at a Declination of approximately -27°. However, the seeing was excellent. The best view was with my 7.5mm LE (212X) eyepiece. The higher magnification provided a higher contrast view of the planetary and the excellent seeing allowed the stars in the open cluster to appear as tiny gems on the black background.

I don't associate globular clusters with winter viewing. However, I found NGC2298, in Puppis, on the edge of the winter Milky Way. It has a magnitude of 9.4 and a diameter of 6.8', so it is quite a nice little globular. At a Dec of -36°, I was surprised to have such a good view. It is quite dense, but I could resolve some of its stars at 212X.

I finally left at approximately 2:30AM. By then the temperature was in the mid-30's, but the RH stayed in the high 70's. I still wasn't tired then or during the drive home. I was stoked by the night's observing. It was the most pure observing fun I'd had since Lassen in July.

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