by Jeff Barbour
Astrobud "El Marko" and I made an early "evening" of Montebello. Rolled out of Boulder Creek well before 7:00 PDST in hopes of catching the Sun through the filtered 80mm Pup. Some forty minutes later, pulled into a rather densely-packed parking area. No, it wasn't the "night crew" of amateur astros. Rather the "day shift": Bicyclists and nature lovers out on a splendid, but warm, late spring afternoon enjoying nature's finest.
Despite our early arrival, we weren't the first amateur's on site. Merak preceded us and we just happened to pull up right next to him. This turned out rather nicely, for El Marko was feeling especially friendly and open to sharing some of his copious experience with others. El Marko, Merak, and I were later joined by Ben. Ben is just getting his feet wet in the hobby and was pleased to get a look at the Sun through the shortube as a start on things.
And what of that view? Best yet through the Pup at MB! Seeing stable enough to fill the 80x field of view with the solar orb. Large group of four main spots ingressing from the east. Two smaller ones taking up point and trail. Train of four small spots leading the main group. Another larger pair north of the equator near the CM. Finally a fourth group approaching the western limb. None of the groups had completely coelesced into single dispersion fields. Those observed in detail all had distinct individual umbras and penumbras. Nor did the main group show much of a depression. However this main group was large. How large? Some say susceptible to naked eye detection.
Sunset last night occured around 8:20PDST. Ten minutes later, Venus popped out for inspection. By this time El Marko and I had swapped out the Pup. Argo took up the mount. Installed the 3x barlow 25mm combo (210x). Turned it on The Veiled Beauty. Was instantly rewarded with a nicely delineated gibbous disk. Eastern limb radiantly brilliant then softening to silver-white at the central meridian. Like the Sun, best view of Venus at MB yet.
Soon Jupiter could be plucked out of the softening sky. There had been quite a bit of discussion between El Marko, Ben, and I about scopes and mount types. So why not? "Hey Ben, think you can point this thing at Jupiter?". Quick tutorial on dead reckoning, a point and a wave at the finderscope - and Ben was off. Within a minute our "newbie on the fast track" had Jupiter centered at 210x. "Nice job, Ben."
Didn't even take a peek through the eyepiece myself (until much later). Ben set right off describing what was seen. Picked out the three main belts (SEB, NEB & NTB) plus a mild post-transit barge in the NEB and equatorial zone incursion to the east. Later I noticed a couple of minor belts (EB, STB & STTB) plus the rift in the SEB and some decent mottling in the polar regions. Not many more views like this before Jupiter goes combust...
By this point Rich had arrived and was piecing together a mount for use with his 5 inch APO. Unfortunately not all components were present so he ended up switching over to a TV76. Meanwhile, Dan also had a TV setup - 85mm flavor. Both scopes gave comparable views of Jupe at lower powers.
About this time Dave dropped by to look in on me and Argo. In fact, it was Dave who first enlightened me about the Montebello observing site (through private email correspondence). Like many experienced astros, Dave is a fine person of cordial manners and well-versed in astronomical lore and knowledge.
Dave is also a bit of an astronomical polymath. Likes to view all kinds of studies. And has just the right equipment to do so. This particular evening, setup a 14.5 inch Starmaster dobsonian, The scope was turned on Jupiter and gave an astonishingly fine view of cloudtops and belt structure. Certainly superior in contrast and resolution to 150mm MCT Argo. Gonna have to do a heck of a lot of thinking about the relationship between seeing stability and aperture. Certainly stability itself was no better than 7/10 - with Jupiter some 30 degrees above the horizon. Something to be said for a well-collimated, large aperture newt featuring diffraction-limited optics...
Time now about 9:30. Skydark wouldn't arrive for another half-hour. What to do? Well since Ben was about, why not pluck a few of brighter doubles out of the sky. Castor and Algeiba made sense. Meanwhile, more conversation about the "right scope" for a beginner. For me it comes down primarily to the type of observing you like to do. For Ben, it was the view of M5 later in the evening through Dave's 14.5...
By 10:00 PDST, the night sky finally darkened enough to implement the evening's observing plan. A plan which included eleven relatively elusive galaxies located in or near Leo's hindquarters. (Framed by stars Beta, Delta and Theta Leonis). But before beginning, El Marko and I cannabolized the two inch diagonal and 27mm Panoptic from the TV85. This gave a nice 67x one degree field of view for our quest. One I was happy to see that Argo easily accommodated...
First up:
NGC 3596 Leo, RA: 11:15.1, DEC: +14:47, Mag: 12p, Size: 4x4, Min Ap: 125mm
Turned this one up as a large faint patch some 45 arcmins southeast of Theta. No real sense of central condensation or frontier. Galaxy appeared entangled with a couple faint (12+) magnitude stars. Definite but difficult through a 150mm under 5.0 ULM skies. About what you'd expect from a galaxy with an average surface brightness of magnitude 13.8 under the conditions.
Next stop, a trio of galaxies located about half the distance between Theta and Delta and slightly east. Finding the two brightest members was pretty straightforward. But neither El Marko nor I could do anything more than imagine the third. First the brightest of the three:
NGC 3607 Leo, RA: 11:16.9, DEC: +18:03, Mag: 10.0, Size: 3.7x3.5, Min Ap: 100mm
This face on sports a starlike nucleus with brightish core and faint extensions. NGC3607 and its slightly dimmer northern neighbor (NGC 3608) were easily detected - even against the greyish murk dominating the low power field of view.
NGC 3608 Leo, RA: 11:17.0, DEC: +18:09, Mag: 11.0, Size: 3.0x2, Min Ap: 150mm
The main difference between this galaxy and its more southerly neighbor was the lack of any sense of spiral extension. Although both galaxies share similar average surface brightness (12.6 & 12.7 magnitudes), the smaller galaxy needs more than the 67x in use to draw out additional detail. (By darkening the background sky and increasing image scale).
NGC 3605 Leo, RA: 11:16.8, DEC: +18:01, Mag: 13p, Size: 1.7X.7, Min Ap: 150mm
Several faint splotches were seen by both El Marko and I in attendance of the two main galaxies cited above. None were definitive. It is likely that these are simply faint star groupings. More magnification may have helped, but I tend to stick with one degree fields during a survey such as this...
The original observing plan called for a sweep to the east-northeast to pick out NGC3626. Instead I somehow stumbled on NGC3659 to the east-southeast instead when fiddling with the knobs on the mount. Several attempts to confirm either of these galaxies went astray. So instead, starhopped from Theta to 81 Leonis, located a neighboring "cup-asterism" in the finderscope and set off after NGC 3655.
NGC 3655 Leo, RA: 11:22.9, DEC: +16:35, Mag: 11.6, Size: 1.6x.8, Min Ap: 150mm
Located a little "lazy Y" asterism in the main tube less than one degree east of 81. This small faint "on the edge" galaxy was just detectable on eye movement slioghtly south of the crux-star of the "Y". This one was on the frontier of never-never land. So hey, the Deepsky Susceptibility Calculator made a pretty good call on this one!
Centering on the tip of the cup asterisms handle, and slewing due north a little more than a degree led to:
NGC 3659 Leo, RA: 11:23.8, DEC: +17:49, Mag: 13p, Size: 2.1x1, Min Ap: 150mm
This galaxy looked larger and brighter to me than the data above suggests. (There was even some central condensation.) In fact this same galaxy was found while slewing east-southeast of the NGC360/07/08 trio. If the same, it goes to show that photometric and visual magnitudes can be quite at odds with one another.
Centering on the western rim star of the cup asterism then slewed due north about a degree and a half to turn up:
NGC 3626 Leo, RA: 11:20.1, DEC: +18:21, Mag: 10.9, Size: 3.1x2.3, Min Ap: 125mm
Here I found a nicely condensed but small patch of light flaring to all directions on eye movement. Another quite definitive find for a six inch scope under marginal seeing.
It was now time to explore that final group of four galaxies that lie on a line northeast of 81 Leonis. Proceeding northeast turned up:
NGC 3681 Leo, RA: 11:26.5, DEC: +16:52, Mag: 11.7, Size: 2.5X2.5, Min Ap: 200mm
Most difficult and quite entangled with an irregular group of four or five faint 12 plus magnitude stars. Some slight sense of condensation and located unexpectedly near 5th magnitude 81 Leonis itself. Perhaps easier than the 200mm minimum aperture might suggest. - Perhaps...
Continuing northeast:
NGC 3684 Leo, RA: 11:27.2, DEC: +17:02, Mag: 11.7, Size: 3.2x1.6, Min Ap: 200mm
A small, faint, barely detectable - yet somehow definitive patch - adjacent to a wide pair of middling brightness stars.
Continuing to:
NGC 3686 Leo, RA: 11:27.7, DEC: +17:13, Mag: 11.4, Size: 3.3x2.5, Min Ap: 150mm
Faint face on. Definite find. No structure - save a subtle sense of central condensation.
And triangulating east of 81 & 84:
NGC 3691 Leo. RA: 11:28.2, DEC: +16:55, Mag: 14p, Size: 1.3x.8, Min Ap: 250mm
Nada. Zilch, Squat. 'Nuttin' Honey...
Throughout all this, El Marko joined me to confirm a number of the "on the edge" galaxies turned up. In general, it was a little easier for me - who found them during slewing (a form of "eye movement" sensitization) to make them out. Complicating the whole process was the fact that the sky was maybe half a magnitude brighter than the 5.5 ULM conditions called for by the calculator in determining susceptibility. Frankly, anything much brighter than the 5.0 ZULM conditions seen at Montebello woiuld have been a complete wash as well as frustrating in the extreme. Perhaps the worst aspect of the quest was the need to "light up" and jot down notes. Argo lacks a drive unit and my eyes lack immunity to even a red filtered flashlight.
The hour now approached 11:15. I'd planned to visit the various globular clusters of late Spring/ Early Summer. Although the following list may not be comprehensive, it is as complete as I am aware of. Over the next year I hope to expand on it. It will prove interesting to revisit from season to season with the same and other scopes. One real joy in observing is the fact that the eye gets better over time at making out subtlities.
NGC 5272 = M3 Canes Venatici, RA: 13:42.2, DEC: +28:23, Mag: 6.4, Size: 16.2, Opt Ap: 80mm
At this point I was still sharing views with El Marko and others. To accommodate various eyes, plugged in the 35mm Ultrascopic and 3x barlow combination for 156x. Nice dark sky background - but seemed to lose something in terms of stellar luminosity. Made out perhaps a hundred scintillating stars. Very few could be held direct...
NGC 5024 = M53 Coma Berenices, RA: 13:12.9, DEC: +18:10, Mag: 7.7, Size: 12.6, Opt Ap: 150mm
This particular cluster exemplifies what is meant by an "optimal view" for a globular cluster. Smallest aperture that gives a nice sense of "mounding up" central condensation, truncation (to the south-southeast) and includes a sprinkling of (a dozen or so) resolved components. Magnification really helps on these "optimal studies". That and better seeing conditions...
NGC 5053 Coma Berenices, RA: 13:16.4, DEC: +17:42, Mag: 9.8, Size: 10.5, Min Ap: 100mm
No sign of 5053 this evening either. The one time (last year) when I did locate it through 150mm Argo was under 5.3 ULM 8/10 stability seeing. James and I have also attempted the cluster using his 200mm SCT (on a previous MB occasion). No luck either. Right now a four incher is calculated to find it, and this is clearly wrong. I suspect I'll be fiddling with the algorithms before too long in order to encompass this anomaly.
NGC 5466 Bootes, RA: 14:05.5, DEC: +28:32, Mag: 9.1, Size: 11.0, Min Ap: 80mm
This cluster looks like a large faint planetary nebula. No sense of resolution - just a ghostly globe with vague central condensation faintly glowing in the night sky. I suspect the globular needs more than than three and change aperture to locate. Have to try it with the Pup. Could be another cause for concern...
NGC 5634 Virgo, RA: 14:29.6, DEC: -05:59, Mag: 9.6, Size: 4.9, Opt Ap: 250mm
Despite the rising gibbous moon, had no problem locating this cluster (at 52x). However, it took 180x (10mm Ultrascopic) to really bring out that "flashlight" effect (caused by its association with a bright line of site neighboring star).
NGC 5904 = M5 Serpens, RA: 15:18.6, DEC: +02:05, Mag: 5.8, Size: 17.4, Opt
Caught this beauty earlier through Dave's 14.5. Absolutely stunning! Filled the entire 120x plus field of view with hundreds and hundreds of resolved members. Wonderful "rose petal" effect made up of numerous star arcs. Picked out at least one possible "yellow giant" as well.
These large dobs are really meant for globulars. Sure you can make out "structure" in some of the brighter galaxies - but globulars are where its at. In the Spring, Galaxies - but Summer's globulars are sensational at 10 inch plus apertures!
And through Argo - at best one hundred stars. Fine but not "sky-shattering".
NGC 5897 Libra, RA: 15:17.4, DEC: -21:01, Mag: 8.6, Size: 12.6, Opt Ap: 250mm
Larger than expected. Visible condensation - perhaps even a bit "granular". Should make a pleasing 10 inch study.
NGC 6205 = M13 Hercules, RA: 16:41.7, DEC: +36:28, Mag: 5.9, Size: 16.6, Opt Ap: 60mm
Interestingly M13 gave a better view than M5. Star chaining more evident. Certainly as many stars resolved. Nip and tuck here for the runner's up honors to Summer's finest M22...
NGC 6341 = M92 Hercules, RA: 17:17.1, DEC: +43:08, Mag: 6.5, Size: 11.2, Opt Ap: 60mm
Several dozen stars resolved - some across the core at 180x. Resolution probably begins at a bit more than 60mms (as suggested by the calculator) however. Certainly have caught a dozen members through the 80mm Pup on a good night. Will have to stop the Pup down and see what I can make out.
NGC 6229 Hercules, RA: 16:47.0, DEC: +47:32, Mag: 9.4, Size: 4.5, Opt Ap: 250mm
Another fine "Virgo Flashlight Globular" class study. Forms an equilateral triangle with a couple 8th magnitude stars. Sports a starlike core, uniform core region, and diffuses at the frontier.
And thus endeth the globular tour. Not much in the way of navigational glitches here. I like these globulars and tend to visit often.
El Marko, Rich and I were the last to leave the parking lot. Scopes all packed away, we talked at length about other observing sites. One that came up was Dino Point. Though lacking in altitude, Dino is well isolated from encroaching light domes. We also touched on issues associated with Fremont Peak. It appears that much in the way of progress is happening, but serious issues still remain with extraneous sky illumination to the south and west. El Marko and I retain our appreciation for the Bonny Doon Ridge. SCAC's airport location is a small scope haven. Frequent 6.0 skies and 8/10 seeing stability. But only available on club nights. Meanwhile, Montebello remains a nice "grab and go" venue. Sure you'll head out aways from the Bay area on weekends, but if you want to limit the mileage during the week, Montebello has a few things go going for it...