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by Randy Muller
Desperate for clear skies and dark nights, I decided to head up to the Sacramento Valley Astronomical Society's dark sky site at the Henry Grieb Observatory on the third quarter moon, October 2, 1999. I figured it would be a relatively short night.
The skies were anything but clear as smoke from numerous wildfires in Northern California blanketed the sky to great altitude. At 5284 ft. elevation, HGO was above some of it, but not most of it.
There were three of us, and a 4th showed up later. The sun didn't even bother to turn red as it set -- its light became extinct long before it set, and we found ourselves in a brownish, grayish twilight world.
Alan Keller -- another TACyon from Roseville -- was set up next to me, and had computers up the wazoo. One controlling his 10" LX200 and a laptop running Starry Night, also controlling his telescope.
He was well prepared, and reminded us of the Minuteman launch from Vandenberg which was to occur shortly after 7pm. I excitedly got my binoculars and looked forward to the rocket launch, having never seen one before.
Alan picked it up first -- a bright yellowish point of light about 40 or 50 degrees above the horizon in the southwest. There was so much smoke that we could see no contrail, but we could see the various layers of smoke illuminated by the flame.
I trained my binos on it, and I could easily see the triangular, fan-shaped exhaust. I watched it for many seconds when suddenly there was a bright flash, and the yellow point of light was gone. This must have been a staging event, but I don't know what stage it was. The Minuteman has 3 stages.
After the staging, all of us (using binos or naked eye) lost the vehicle. I continued searching for it, and I re-acquired it and continued to follow it.
The point-like flame after the staging was distinctly bluish and much fainter, whereas before the staging, it was yellowish and extremely bright. The point of light just seemed to hang in place while it slowly got fainter.
Some time later, we all noticed a very bright satellite passing overhead, going from NW to SE, it was very bright and I trained my scope on it, at 55x. It was very large, but I could not make out any detail. It seemed boxy, non-circular and clearly irregularly shaped. The angular extent was much larger than M13. Alan announced that it was the Internation Space Station, according to his software.
When it finally got 'dark', it wasn't dark. The conditions were only slightly better than the mag 4.5 skies at my suburban home in Roseville. I estimate that they were about mag 5.5 in the zenith, and probably about mag 3 in the south, where the worst of the smoke was. No, the worst of the smoke was west. No, north! The horrid smoke was all around.
The Milky Way was visible, but it was strangely subdued. Most of Sagittarius in the south was completely invisible. It was heartbreaking to see the sky like this. We began discussing going home. The seeing seemed to be pretty good, so we held out hope that Jupiter and Saturn might look pretty good.
I was reminded of the quote from Psalm 139 used in the Episcopal Church Evening Prayer service:
If I say, "Surely the darkness will cover me, and the the light around me turn to night," darkness is not dark to you, O Lord; the night is as bright as the day; darkness and light to you are both alike.
In this charcoal gray soup, I only saw one new object -- a galaxy. I failed to find a number of objects, and I accidentally reobserved a lot of stuff I had previously observed at Lassen and at HGO last year. I need to organize my observing program better. At a minimum, I need to check off stuff I've seen (maybe with the date) in the "Night Sky Observer's Guide" books, since that is what I was using.
One guy named Steve, who I've never met before, had a homemade 12" f/6 truss-tube newtonian on a altitude-azimuth fork mount. That is the first time I've ever seen a newt on a fork. All others I've seen are either on equatorial mounts or on Dobsonian mounts with a rocker box supporting large bearings.
I asked him if he got that idea out of a book or something, and he said he was just winging it. Unfortunately, it wasn't balanced, and he didn't have a finder on it. It used only 4 truss tubes arranged as the edges of a simple rectangular parallelopiped (ie., a box), and was therefore not rigid. He reinforced it with diagonal support wires with little tie rods so he could make it as taught as he wanted.
These wires apparently solved the rigidity problem.
Eventually Jupiter rose high enough to look at, and it was simply amazing.
Typically as I watched it, Jupiter would be somewhat blurry for several minutes, but pretty good. Suddenly the air would stop moving, and I would see it crystal clear, as in a photograph. It always took my breath away when this happened. It was like someone pulled aside a heretofore invisible veil, revealing Jupiter in full clarity. Once when this happened, I shouted involuntarily, the same way I sometimes do when a bright meteor flashes across the sky, or through the field of view.
It wasn't actually like a photograph -- in certain ways it was better. Though the colors were much paler than I've seen in photos, and the image scale was much smaller, there seemed to be a delicacy of shading and level of detail that is missing from earth-based photos, particularly from smaller aperture scopes. And, unlike a photo, the scene was evolving as I watched it: The Great Red Spot was making its way across the face of the planet, and the turbulent area of the South Equatorial Belt was coming into better view.
In these moments of clarity, which often lasted 10 seconds or more, I could see enormous detail in the cloud belts and zones. I counted 6 dark belts, not including the polar regions, but I am sure there were more belts: In the polar regions they became progressively smaller, thinner, closer, and blended together to form a brownish cap with what I can only describe as 'rhythmic features'.
The South Temperate and South South Temperate Belts were blended together, and I could not see any break between them. As a group, they were clear and distinct from the surrounding zones (light areas).
The Great Red Spot was very prominent as a small dark reddish-brown, contrasty spot in the large and pale Great Red Spot Hollow, which breaks the continuity of the South Equatorial Belt. The GRS was very small but very dark in this hollow. Immediately preceding the GRS Hollow, the SEB became very compressed and dark, making a hard turn to the north. Following the GRS Hollow, the SEB was filled with dozens of tiny white spots in a turbulent chaotic morass.
The North Equatorial Belt showed wisps and extensions south into the Equatorial Zone. A small, thin Equatorial belt was present, which I've never seen before, though I've seen it sketched in books sometimes. It was broken and faint in some areas.
The North Temperate Belt below the NEB was thin and dark and well defined. It was not as dark at the NEB. The North North Temperate Belt was also clearly visible and well defined.
I attempted and failed to split the companion (aka "blue buddy") of Gamma Andromedae. With a separation of only .4", this is slightly below the Dawes limit of my 10" scope.
At 11:30pm the runway lights and search light came on, triggered by a signal from a passing plane, who was no doubt lost because they could not see Sacramento in all the smoke.
Eventually Saturn rose high enough to view, but the seeing was deteriorating fast. It looked good, but in an average sort of way. Still, I could easily seen the Crepe Ring, Cassini's Division, several moons, and the broad, dark South Equatorial Belt.
Glancing back at Jupiter confirmed that the seeing was much worse, so I packed up, happy that the seeing had turned the evening from total loss into total joy.
| Date | October 02/03, 1999 8:00pm-12:00am (0300-0700 Oct 3 UTC |
|---|---|
| Location | HGO (near Sacramento) |
| Altitude | 5284 ft. |
| Instrument | Orion DSE 10" f/5.6 dob-newt |
| Oculars | 7.5, 10, 17, 26mm Sirius Plössls |
| Seeing | 9/10 Unbelievably fantastic |
| Transparency | 5/10 Lots of smoke |