Witchcraft and the Rise of Atlantis

1997 Sept/Oct

During the first dark of the moon after the 1997 autumnal equinox, in late September and early October, I had three good observing nights at Fremont Peak State Park, near San Juan Bautista, California. Each time I took my Intes 6-inch f/10 Maksutov. My main observing program continued to be chasing down the last remaining of the 2500 or so deep-sky objects discovered by William Herschel, that I have not already seen. I logged about 120 during those three nights -- I have not quite 400 to go.

Six inches of aperture makes a Herschel hunt very challenging, but with practice, good technique, and dark sky, almost all are detectable with no more than a little bit of magic. I have been working mostly with exit pupils of 1.5 or 1.6 mm -- magnifications of 90 to 100x, a lot more than many people use for deep-sky work with so small a telescope. But they work fine, and push the telescope's limiting magnitude, for galaxies at least, a good deal beyond what I can do with lower magnification. There is a side benefit, too -- with that much magnification, observations are less sensitive to background sky glow -- I have done a little of the work with as much as a four- or five-day moon in the sky. The problem then becomes one of shielding my eyes from background glow that does not come through the eyepiece. I have been using my pirate's eye patch (Arrrrr!!!), and assorted contortions of hands and distortions of hat and of jacket collar, to ward off the light.

The most common problem is not that objects are too faint, but that faint objects are too close together to detect as separate. NGC 1633 and 1634, in Taurus, are an example of such a pair that I found just barely separable in the six-inch. They are about an arc minute apart, and both have magnitudes of 13 or 14. (Your mileage on magnitude may vary, depending whose numbers you use.)

Now and then I take a break and look at other things. On the evening of 4 October, another observer was using a Pronto to chase down some faint nebulae, and wondered whether I could see IC 2118, the Witch Head Nebula, with the Intes. This several-degree long sprawing nebula in eastern Eridanus is really too large for comfortable viewing with that telescope, but I tried. With my 32 mm Erfle eyepiece (two-inch barrel) and no filter, we swept from beta to lambda Eridani, and found a glowing patch about half way between the two. That was encouraging, so I put in an Orion Ultrablock filter. The patch was more prominent, and we could also see another patch, about half way from the first one to psi Eridani. A good view of this object would require a rich-field telescope with a much larger field. Nonetheless, I was pleased that the Intes was doing so well, particularly since that part of the sky was only some thirty degrees up at the time. Better conditions might have yielded more of the fainter part of the nebula.

Yet the most wonderful astronomical sight of that dark moon was not a deep sky object at all, it was the spectacular pass of Mir and space shuttle Atlantis on Friday evening. I observed this one from my home in Palo Alto. Atlantis was slightly the brighter of the two, almost a dazzling white as her flat trajectory arced up from the horizon and past Jupiter, with Mir in close pursuit behind, as I watched naked-eye and with a 10x50 binocular.

Jay Reynolds Freeman 1997 Oct 6