More Aperture Fervour at Fremont Peak

by Jeff Barbour


Special Observing Report

Fremont Peak: May 31, 2002


Sooner or later it was bound to happen. I'd begin to appreciate the virtues of sheer size. Aperture definitely has its place in the scheme of things astronomical. Sure, you can get fine views of Moon, Sun, planets, and doubles through a four to six incher. And yes, a ten incher can lay bare numerous stars in the brighter/nearer globular clusters. Bumping things to twelve inches adds some satisfying views of the brighter galaxies. But if you really want to go deep, double up on that.

Thirty inches will do, and quite nicely...

And thirty inches lies about an hour and fifteen minutes (plus half hour stop at Mission Burger, San Juan Bautista) from Backyard, Boulder Creek.

Last evening it was "El Marko's" turn to join me on the trip south and east. For the first time I was going to Fremont Peak sans scope. No Argo, Vicki, or Pup this time. All we needed was a decently dark sky, a little retinal adaptation and the FPOA observatory to loose the magic genie of aperture.

But the sky gods had their own plan. Although the sky was dark (certainly 6.0 ZULM), it was not steady. Strong, dry gusts of wind broke in on us from the south. Lightning illumined the be-clouded sky to the east. By midnight, we abandonned our quest. Scope and observatory roof were by this time imperiled. Using good judgment, beneath an otherwise splendid sky, we shut things down.

But not before Galaxian El Marko had had his pallette whetted. And all in attendance had dined sumptuously on phat photons sourced from distant island universes. No, we were not sated. But we were impressed - immensely impressed...

The evening started jauntily. Introductions were made. Paul brought along college roommate Michael. El Marko, Paul, and Michael had at one time all lived on the same island - "LongIsland", New York. Meanwhile, my own Connecticut roots didn't exactly distance me from this trio of ex-patriots.

Well before the last solar glow faded to the west, the sky overhead was already quite deep. There was talk among us of a few disparate doubles. But Upsilon and Iota UMA were a bit too vertical. And we settled on a more amenable Kappa Leonis. There we learned that the winds buffeting us were not a "boundary layer" phenomenon. No, like the legendary turtles supporting the earth, it was turbulence all the way up. 4.6 magnitude Kappa shown brilliantly in the 30 incher at some 200x. But Kappa was also "large" and swallowed up its dim confere. For several minutes, I watched the primary's spurious image expand and contract like some inverse pupil regarding me with ambiguity. No glimpse of the closish tenth magnitude companion was possible. My short list of seemingly impossible disparates now awaits some future night at the observatory.

We made our next leap From western Leo to southern Virgo. This proved to be the only large leap of the night. Mounting winds precluded implementation of the default observing plan crafted earlier in the day. Nor were we able to drop in on Globular Cluster M5 in Serpens as El Marko had hoped. But that view of a "sunken brimmed" Sombrero was nearly as astonishing as that during theAstronomer's visit to Hotel California earlier in the month. As before there was that glow of the remnant core beneath the black-honed lane, but what impressed this time was how the main core region and extensions "sunk into" the lane. A very easy, very comfortable, and very nice fit. This particular "Sombrero" was worn with panache...

Of course once you've entered Spring's Realm of Galaxies there is no end to the possibilities - especially when everything magnitude 15.5 and brighter lies within your grasp. So we slewed almost due east to take in:

NGC 4680, Galaxy in Virgo, Mag: 13.4p, RA: 12h47m, Dec: -11°39, Size: 2?x1.5?, ASB:13.4? Min Ap: 10"?, Opt Ap: 24"?, X: 166

Here was a galaxy that would be a difficult find through 150mm Argo on even the finest nights of transparency. The galaxy displayed as much structure at the eyepiece (orientation, frontier, central condensation, core region, and faint extension) as that of the Sombrero through that same modest six incher. While contemplating this elliptically presented galaxy, we noticed a roughly 14th magnitude blue star just east of the galaxy's frontier. The star appeared visibly brighter than the galaxy's core. Since the star did not appear on the SkyMap Pro chart, we superimposed an image from the 48 inch Palomar sky survey. This confiormed that what we were seeing was not in fact a supernova. The presence of the star added another dimension to the evening something novel and unexpected.

From NGC 4680, we resumed our sweep east and slightly north to:

Name: NGC 4700, Galaxy in Virgo, Mag: 12.8p, RA: 12h 49m, Dec: -11°25', Size: 3x.5, ASB:12.0 Min Ap: 6", Opt Ap: 10", X: 305

Under the 6.0 ULM conditions of the evening, would have had little trouble turning up this galaxy through six inch Argo. Meanwhile, a ten incher would give a decent view of this irregular edge on. Given its presentation angle, and access to a thirty inch, you'd expect some incredible detail to be revealed. And certainly that was the case. We could easily detect a very credible "notch" southwest of the core at both 166 and 305x. That same vaguely condensed core, was also echoed to the northeast by a second condensation. What we were seeing here is likely a massive star-forming region such as NGC604 in the Triangulum Galaxy. Overall, the entire galaxy was reminescent of what a good six incher will show of M82! And like M82, no dust lane bisecting the galaxy was detected.

Northeast of NGC4700 (and only on the Palomar sky survey image) we noted a faint "fairy ring" of nebulosity. Would the 30 incher show it? As a matter of fact, it hung right on the visual threshold. But it was Michael's call on the orientation (SSE by NNW) that confirmed it. This undesignated deep sky chimera did in fact lay within the grasp of the thirty incher. Imagine that, navigating to undocumented studies based on sky survey images generated by a major observatory. Now that's aperture!

While questing after a fourth galaxy, came across a slow moving satellite in the field. Paul seized on it instantly as a "geosync". Unplugging the clock drive, we centered and watched it dance to the wind against a backdrop of fifteenth magnitude stars...

While not actually looking through the big scope, I sweeptthe southeastern night sky using the observatory's scissors-mounted 11x80mm binoculars. The reach of these things was stupendous. Imagine trundling together a couple of ST80's bearing 35mm eyepieces. Add to this a perfectly dark night sky. Include M5, Comet IK, the Lagoon, and Trifid Nebula and vast stretches of the Milky Way. Gorgeous!

By midnight, the winds were making their final, successful push to dislodge us. Hurriedly, we turned up a pair of galaxies in western Corvus: NGC4038/4039 - "the Antennae Galaxies". Both members of this colliding pair showed much of mottling and irregular structure. Together they appeared more like two dimpled ventricals of a human heart. This "Antennae" description doesn't quite work for me. Why "St Valentine's Duet" makes for a much finer appellation!

With the observatory near-bedded down, we made quick exit to turn up a low sky northeast view. Two successive Iridium satellite flashes were in the offing. We watched as a brilliant negative magnitude star took form near the treeline. This led to a crescendo of luminosity. Followed by rapid extinction. Within fifteen seconds, the first Iridium had dissappeared. Five minutes later and with the observatory locked down, we exited for the final time. The second Iridium flared and followed its confrere to the southwest.

Our own departures were far less flamboyant, but carried a very definite sense of travels to come...