Sunday, March 31, 2002

A night a La Caja de Los Gatos Observatory 3/31

Last night I had the 14.5" f/5.6 Dob set up in my backyard, to take advantage of a few hours of dark. I planned to use the Night Sky Observers Guide's selection of deep sky objects in Leo, then move on to some remaining targets on my Herschel 400-I and 400-II lists.

At dark, about 7:45 p.m., the transparency was outstanding, maybe 8 of 10, and steadiness very good, little twinkle even on Sirius. I guess temps were about 65 F. Very comfortable, I began the night in a t-shirt.

The first object was NGC2903. This is an object I use regularly when up to gauge transparency. The view at 103x (20 Nagler II) was astonishing. Obvious, large, bright, easily seen with direct vision. This had to be one of the best in-town views I've had of this object. I could easily see the small bright core, while the rest of the galaxy's thick body extended about 6'x2.5' NNE/SSW. The core was also interesting, as usually a core seems to be either stellar or just slightly fuzzy... but in this case it was clearly fuzzy and elongated along the major axis of the galaxy. NGC2903 is easy to locate, 28' S of Lambda Leonis (Alterf, SAO 80885) a nice type K5 star marking the nose of Leo and shining at mag 4.3. NGC2903 has a surface brightness (SB) of 13.6 and is about twice the size I detected.

NGC2911 shares the field with NGC2919 and NGC2914. These were very faint but identifiable. Increasing the magnification to 172x (12mm Nagler II) helped by increasing the contrast. The galaxies have surface brightnesses of 14.2, 12.8 and 13.4 respectively. I began with the pretty double star (golden and blue/purple) 6 Leonis centered in my finder. The small galaxies are framed by a distinctive pattern of stars... I saw them forming more or less a rectangle of six stars, in two pairs of three running NE/SW. The most obvious galaxy was NGC2911, just outside the line formed by the pair of stars making the SE end of the rectangle. The galaxy would swim in and out of view, and seemed to be elongated NNE/SSW. NGC2914 was fainter and located just E of the SE star in the same pair. It appeared elongated N/S. NGC2919 was the most difficult, a small roundish hazy glow with averted vision was all I could detect.

Next I moved back to NGC2903 in order to hop to its close neighbor NGC2916. This object is at the end of a chain of four stars E of GSC 1409779, which sits close and NE of NGC2903. The chain terminates when it intersects another chain of five stars (including the last star in the chain of four) running mostly N/S. NGC2916 is just beyond the intersection of the two chains and just N of a close pair of mag 12.5 stars. The galaxy appeared elongated in the same PA as the pair of stars. NGC2916 has a SB of 13.4 and is 2.5'x1.7' type Sb.

I thoroughly enjoyed the view of NGC2964. This target seems to be in the "middle of nowhere" but using Alpha Lynx, 38 Lynx and SAO 61254 (Lynx) as guides it is easy enough to move back toward the empty space above Leo's head to SAO 61633 (mag 5.9). A nice close double star sits just E of my finder star, SAO 61633, and helps determine direction. The galaxy sits at the end of a chain of stars to the NNE. It is elongated WWSW and seemed to be about 2'x1.5' in size. I could hold it with direct vision. Another galaxy, NGC2968 is visible about 6' to the other galaxy's N. When visiting these two galaxies make sure to note the gorgeous gold star that begins a chain of three pointing directly at NGC2964. Very pretty star field!

I spent some time next looking for NGC3020, 3016 and 3024. I certainly identified the field, there is a nice elongate "L" of stars (GSC 834:395, GSC 834:1197, GSC 831:505, SAO 98778) to the SW. In all, four galaxies sit in one field here, but this night they just teased me. Sometimes I thought I saw them, then I would doubt it. Ghosts playing hide and seek. I think this would be a very nice field from a dark sky. Their surface brightnesses are 13.5, 12.9 and 12.9, which makes me think conditions were beginning to deteriorate since similar SB targets were found earlier in the evening.

Next was NGC3032 - which I found much easier to observe than the 2 star rating in NSOG infers. Finding it was pretty easy too, using SAO 81004 (Epsilon Leonis) and SAO 81064 (Mu Leonis) as guides. The galaxy sits nicely framed between a pair of stars, mags 9 and 11. It has a bright core surrounded by a small round glow, making it look more like a planetary nebula than a galaxy. This object has a SB of 13.8... but the bright stellar core made if much easier to find than the SB would otherwise indicate.

The next target was NGC4133, the first object of the night on my Herschel list. Located in Draco, it is just E of the halfway point between the pointer stars in the Big Dipper and Polaris. A naked eye "teaspoon" asterism of mag 5 stars helps locate the field. The galaxy is elongated N/S and is easy to hop to from the handle of the teaspoon - SAO 7540.

It was now about 10 p.m. and conditions had changed. I put on two more layers of clothes and could still feel a damp chill in the air. Books, notes, laptop, all were feeling a bit wet, and I was finding the 20 Nagler fogging up. I kept trying but would quit after two final objects...

NGC4168 is a roundish bright galaxy set at the W end of a chain curving away to the E. I felt lucky to pick up this galaxy, it was quite dim (SB 13.2) due to increasing moisture content in the air. What was neat was the accidental view of NGC4216 one field to its E. In a darker sky, 4216 would make a great target combined with two other edge on spiral galaxies framing it (NGC4206 and NGC4222).

I finished with NGC4241 - a pair of stars sit just S of this galaxy, with an elongated triangle of dimmer stars still further S and pointing to the E. This pattern helped locate the galaxy. I had to use averted vision to pick it up, and there was no hope of finding its neighbor IC3115.

It was now 11 p.m. and I realized the moon had risen almost 40 minutes earlier, although hidden by the large oak in my neighbor's yard to the E. No wonder things were getting more difficult! I thought it was only the moisture, but add to that the brightness in the eastern sky, and it was time to pack it in for the night.

I tipped down the scope and put it to bed with its night-light. It was great to be out back again.

Thursday, March 14, 2002

In town observing report 3/14/02

Last night I was able to observe twice with two different equipment setups.

Early in the evening, just after supper time.... I took my 10x50 binos and Virgo binocular mount around the corner to Fisher Middle School in Los Gatos, and set up on their outdoor basketball courts. My wife Pat, daughter Mimi and her friend Ashley accompanied me. I set up in a dark area near the gymnasium.... which actually looks like a primo spot for a small (8") scope.

I described to Mimi where the comet was, talking her from Alpha to Beta Arietis and then halfway to Eta Piscium. The comet was there, easily visible, very bright coma that looked fuzzy but really almost stellar in its brightness and compactness. The tail was quite long, reaching eastward toward a single bright star near the top of the field. One could almost imagine a two-headed comet! Everyone enjoyed looking at this, but to Pat this was a rather disappointing view since her idea of comets is Hayakutake and Hale-Bopp! Mimi and I have, I think, a different appreciation for the nice view, since we have spent many nights together hunting much fainter objects.

I then turned the binos on other object. M31 was first. I did not describe it, but told Pat to look and tell me what she saw. She described an elongated glow pointed "up and down" (E/W) in the field. She felt it was not something she would have noticed without my telling her there was something there. True, it was low in the sky, but I knew transparency was not all that great. M31 should be a great binocular object.

Next were M47 and maybe M46, M45 (Pat loved this!), M42 which showed as a nice glow around some bright stars all involved in a much larger rich star field. Up to the belt stars to enjoy the view of all three in one field with the gorgeous sweeping chain snaking through the western pair. What a view! Both Pat and I saw M81 in the binos. Soon, we packed things up and headed to drop off some videos at Blockbuster.

I had uncovered and checked collimation (perfect!) on the 14.5" f/5.6 Dob in my backyard. Because the Herschel objects I am interestd in are mostly spring targets, I waited until after 11 p.m. to go outside. The breezes that had been blowing in Los Gatos during the afternoon had subsided. It was not all that cold out and seemed a perfect opportunity to get 2 to 3 hours observing in.

I began in Crater. This was just over the "tree-line" (my neighbor's 25 foot tall untended shrubs) to my south, but I could see Corvus and a few of Crater's stars. So off I went to find NGC 3892. Well, I decided to follow my rule, if I don't get it in 10 minutes, cut my losses. I was able to identify mag 4.7 Theta Crateris, but could not find the galaxy from there.

Well, that one was a Herschel 400-II object, so the next one would surely be easier as it was an Heschel 400-I. NGC 3938 is in an easy to locate position in Ursa Major, high overhead, nearly in Dobson's hole. I swung the scope up and soon had located a good landmark... 67 Ursae Majoris. That star is a wide double and beside being easily identifiable it is plain gorgeous.... a close grouping of bright stars ranging from mag 5 to mag 9. Using these stars I could determine what direction to go. Soon I saw a galaxy.

What surprised me was how dim the galaxy was. And its shape. I looked at first like a fuzzy star, but soon I saw a bulge and long extensions. This certainly did not fit the description of NGC 3938! I had found the dimmer NGC 4013, on the way to the brighter galaxy. I pumped up the magnification and wrote the following:

Stellar core with 12 Nagler. Around the core was a round glow, like a small dim globular cluster. Soon the galaxy revealed extensions ... quite long, running WSW to ENE. I thought I might be detecting a dark lane along the major axis and just N of the bright core.

I kept coming back to this object while attempting for find NGC 3938, but I never did find it. I began to think the seeing was deteriorating, as NGC 4013 was becoming increasingly difficult to detect. Soon I began noticing bloated bright stars. I could not get focus.

What I had been concerned about earlier in the day, the jet stream plowing down directly over us from the north, was making it difficult to pick out dim object. The seeing had gone bad.

Looking at the sky again I noted how high Arcturus was, and decided to try the seeing on M3. Very soft. Many stars, but not pinpoints.... defined, but rather hazy looking.

I knew the night was over.

But, before tucking the scope away for the night I pointed it between Denebola and Vindemiatrix, deep into the heart of the Virgo Cluster. Even fuzzed out, this was a great sight. It seemed everywhere I moved there were galaxies... barely a field went by without something non-stellar. At one point I wondered about two bright galaxies... elipticals.... could these be M84 and M86? Was I at Markarian's Chain? The answer was yes... I could identify NGC4308, that makes the galactic triangle I associate with the start of the chain. I could not see dimmer NGC 4402, and when I saw that NGCs 4438 and 4435 (The Eyes) were pretty dimmed out... I knew the night was done.

Although I had not gotten to see what I had hoped to, it was a nice hour out back. I felt refreshed and had, in fact, had a number of nice views during the evening. Looking this morning at an image of NGC 4013, I felt good that I had gleaned so much detail on a rather mediocre night.

Friday, March 8, 2002

Houge Park fun

At Houge Park we had intermittent clear and murk. There was very good planetary detail, a couple very dark barges transited Jupiter as the night wore on. We too had a nice view of the comet, best at low power. I thought the view through binos was the best... a very bright coma and obvious tail a good 5 degrees long or more, as a guess based on the FOV of the binos. In my 8" f/7 with a 50mm eyepiece the coma was very pronounced, but the tail faded a bit compared to the view in binos.

The public turnout was okay early on but grew sparse after about 9 p.m. I was showing them M42, which had wonderful detail, M81/82, M35 (NGC 2158 was barely detectable). NGC 2903 was nearly impossible, which to me meant the transparency was not so great. M65/66 were there, but nothing to write home about. The Eskimo Nebula was plain gorgeous.... it was funny too, since I found it with the 50mm eyepiece.... someone asked if it was in the field so I told them yes... it appears nearly stellar ;-) which at that power it did. But we pumped up the power and the disk and central star were a wonderful contrast with the close by bright star.

I then began looking at double stars. The public enjoyed Gamma Leonis.... the nearly identical close golden stars were spectacular in color and brightness. Then, for a challenge, I found Zeta Cancri at about 75x and could see two of its components. This is a really outstanding multiple star system... I put in my 3.8mm eyepiece to bump the magnification to about 375x and the star split again.... two very tight stars with the dimmer tertiary close by. The system is probably contains five stars... but one is too tight to detect visually (companion to the tertiary) and the other thought to be a white dwarf. Zeta Cancri is well documented in Burnhams, worth a read, worth a look. I was most pleased at the views my 8" gave on this star.... beautiful pinpoints... even though I did not collimate the scope after arriving late.

The rest of the evening was spent with friends hanging out. We had a nice surprise when Ken Miura showed up, stopping in to see the old gang while travelling from Tokyo to Boulder. We may get to see him again next weekend at Coe or Dino. Others who stopped by were Rich N., Denny W., Marsha R, Ken H, Daniel S, Kevin R and Kevin S, Bob H, Mike K and others. Fun night of in-town buds and observing.