Tuesday, November 01, 2005

20051031.1930 - Touring the bright stuff - Observations

Session Name: 20051031.1930

Location: TotL, Central Park, NYC
Site Classification: Urban
Date/time: 31 Oct. 2005, 7:30pm ~ 1:15am

Seeing/Transparency/Darkness: 3/3

Conditions: Clear, moonless night. Some gusty breezes later in the evening, frequent and heavy enough to make the back of my neck cold. Mild temperature. Rockfeller Center building continues with light show that is very annoying and definitely adds brightness to the manhattan south sky. Weather history for
31 Oct. 2005 at wunderground.com

Teleport 10 reflector, F/5 254mm reflector

Pentax 40mm :: 72° :: 2.3° :: 32x
Nagler 17mm :: 82°:: 1.1° :: 75x
Nagler 13mm 82° 0.8° 98x 0.8°
Nagler 9mm :: 82° :: 0.6° :: 141x
Nagler 5mm ::82° :: 254x
Tele Vue 1 1/4" Barlow 2x


Solar System

- Mars -
Last night and tonight some amazing views of Mars with the 10". I was saying this after using the 4" because I could magnification but the resolution and contrast diminished. From the 2003 opposition, I am a more experienced observer, have a larger scope and the altitude reached has provided some very rewarding views of Mars. I can use mprovement in learning the features.

This night, I observed Mars on 4 separate occasions, watching it rise above our horizon when Syrtis Major was rotating on to the disk. Same as yesterday, the "gully" between Mare Tyrrhenum and Mare Cimmerium was evident central on the disk. Early on it required moments of steady seeing but as Mars rose, seeing it improved considerably. A section of Phaetonius inside of the northeastern limb was visible as a small crescent shape, just as yesterday. Amazonis, on both nights, struck me as a yellowy-orange color - an ochre hue. On subsequent observations, Syrtis Major moved across the face of Mars, faint darker toned wisps like taffy pulled upward towards the South Pole. On both nights, I had a difficult time identifying Hellas. I could only detect it by the contrast to the north where Iapygia wraps it and Mare Serpentis reaches around. The southern side has yet to pop into definition for me. The final observation was when Syrtis Major was central on the disk, Mare Serpentis and a dark toned stretch to Mare Erythraeum on the western limb, the “y” shape more pronounced.

- Saturn -
Yeah!! Saturn is coming back. Last time I saw it was late, late morning just prior to sunrise from Custer. Tonight around 1:00am, it cleared the trees, but was awfully low. It was difficult to get focus on it with 5mm and I quickly swapped to the 9mm. Still Saturn suffered but not enough that I could make out the North Pole peeking out from behind the rings. Titan and Rhea were apparent to the west. Charlie was able to pick out a band of color running across the face.

Stellar & Deep Sky

The list of seen and attempted (*) objects. I enjoyed staying with the low power eyepiece, 32x, for observing open clusters. I swapped to 75x to increase the number of stars and to inspect them for doubles, color, or any other detail that may appear. Only the globular and planetary nebula were observed under high power.

Iota Cas
Milky Way
Messier Catalog: 15, 31, 32, 110*, 34, 35, 36, 37, 38, 42/43*, 45
NGC Catalog: 1023*, 1502, 1907*, 2281, 2392
Asterisms: Cheshire Cat, Kemble's Cascade

- Milky Way -
After Charlie had setup and observed for a while, I asked him to swing his bins into Cassiopeia. Earlier when I was aligning the Rigel finder on alpha Cas with the low power Pentax 40mm EP, I could sense the Milky Way. This is the second evening in a row where I feel confident that I am seeing the Milky Way. The night before, I noticed it when observing the starfield around mu Cep with the handheld bins and tonight it was apparent in the field within the upper "square" [beta-, alpha-, gamma-, kappa Cas] of Cassiopeia. It is unmistakable as soft glow that doesn't resolve but provides a grainy white background that brighter stars emerge from.

- Kemble's Cascade - NGC1502 - NGC1501* -
One of the first objects that everybody turned their optics to was the asterism Kemble's Cascade. In my scope, I can't get a large enough field so one has to meander along its length with two fov's. At the end, one of my most favorite clusters, NGC1502, is perched at the tip of the E end of the "bird's foot". Faint star specks resolve beneath and around the bright double that dominates. The concentration of fainter stars runs along a NW to SE line, cheating towards eastern star of the bright pair.

I wanted to observe NGC1501, but not recalling which way to go relative to the bird's foot, and unable to recall the starfield in low power, I abandoned an attempt to locate this planetary nebula.

- M31 - M32 - M110 -
Mike O'Gara & I observed M31 and spoke of how large Andromeda appeared when we described the extent of its core. The nucleus is nearly stellar and the core has a slight, gradual diminishing 2nd level and then the edge continues on with a faint wispy glow. I would guesstimate that the length was better than a degree and half, maybe two, and the width could easily have been a half a degree or better. In the same fov, M32 contrasts nicely with its brightness profile as it is fairly even across and then ends abruptly after a small diffuse edge. We observed with 32x and, predominantly, 75x magnification.

As usual, I looked for M110, which was not detectable. I follow a trail of mag9 stars on the NE edge of M31 wrapping around to a triangle of mag9 & -10 stars. In the fov, it should be sitting right below them.

- M38 - M36 - M37, 1907* - NGC2281 -
Charlie and I observed these objects at 32x and 75x. We compared contrasted their size, light profiles, range of stellar magnitudes, and described the shapes/patterns we see of or within them. I like M37 with its even glow of mostly equally bright stars. There are a few that shine brighter but this open cluster is dense, rich with stars. In the scope, mostly at low power, M37 retains that nebulous character as opposed to M38 and M36. Both of these are blown into resolution displaying a broad range of stellar magnitudes. Charlie prefers M36. I assume it’s because of its brightness and ease to see in the bins. Tonight I was able to see all 3 with the handheld 7x50 bins. M38 which I normally don't see excited a sensation on my left eye where I was able to describe it, in agreement with Charlie, as an equilateral triangle as described above. M36 is easy and M37 is more difficult, though not as difficult as M38.
Recalling from a recent trip to Custer Institute, NGC1907 was a very conspicuous knot of stars next to M38. Tonight I was looking for it but nothing stood out. Not having the Palm, I had nothing to reference. I looked in the field and notice a clustering of stars further south where the Cat's nose is. What I identified as NGC1907 was incorrect as I looked too far south. It is much closer to M38. Thus, at 75x I was unable to detect and identify it.

While in the neighborhood of Auriga, I happened over to NGC2281. Last night, we observed this in Ben's 10x70 bins, as an obvious cluster embedded on the leg of small triangle. This open cluster is an easy, obvious open cluster to locate. It makes an isosceles with beta- and theta Aur, where I estimated about 7 degrees, four or five bright stars which I was able to make out a 2 degree long right triangle. This points right to 2281.

What was nice about this double Y-shaped cluster was that the diamond, or as Charlie described as a parallelogram, making the stem of the Y were two doubles. One was an equal pair, while the other was a closer unequal pair. The unequal pair had a nice color contrast.

- M35 - NGC2392 -

I starhopped through Gemini consistent with tonight's strategy: Stay with bright and easy to locate objects. M35 easily falls into this category, as it was visible in the handheld bins and easy to place a large fov into the general area of the twins foot and sweep to this large, bright, somewhat loose cluster.

From there, using Erich Karkoschka's atlas, I went to to the planetary nebula, NGC 2392, also called the Eskimo Nebula. This was one of the rare times where I stepped up the magnification and observed a DSO at 141x and 254x. This nebula did not exhibit a strong blinking effect where direct and averted only changed the nebulosity’s size slightly. The nucleus is brilliantly stellar compared to the surrounding nebula. I sensed neither color nor any change in brightness from the nebula.

- M42 - M43* -

One of the last deep sky objects, Charlie and I finished up on was M42. This was a magnificent view, in spite of Orion still rising from out of our horizon. Nice undulations of light and dark rip through this nebula, appearing like billowing clouds. Dark, thick bands impede one very noticeable one in the NNE. Charlie described this very dark band (dust?) as a large "cavity" in this tooth-shaped nebula. Beyond this intruding dark lane, the nebula reappears and extends farther into space. The Trapezium resolved with ease, however, we were unable to resolve cleanly the E & F stars. Perhaps it was because this was still low in the sky, but I think the scope alignment was off at this time. One noticeable artifact was that one of the spider diffraction spikes was doubled. There was even brightness and length among all of these spikes with exception that that one had dimmer, conspicuous partner subtending an angle of say 10° ~ 15° from the center. The scope had been raised and lowered an number times when observing objects low and high, undoubtedly causing the mirror to move around. Nonetheless, M42 was a beautiful sight!

I looked for M43. I consider this nebula as difficult under our city skies. When it is present it is a curled shape tear drop about a star north from M42. I didn't take notice of it tonight and only looked briefly for it, not giving the effort that it normally requires.