More Suburban Astronomy
By Jay Reynolds Freeman

On the evening of March 21, I again set up my Intes 6-inch Maksutov in the driveway of my home in Palo Alto, hoping for a good view of Comet Hale-Bopp. Spring temperatures and a balmy evening let the optical tube assembly come to thermal equilibrium in the back of my car in less than an hour, while I was eagerly awaiting nightfall. I spotted the comet naked-eye against blue sky at 1850 PST (0250 UT March 22). The line of sight was over, under, around, and through: Fortunately, my driveway points northwest, and there was just space enough between my redwood and the palm on the next block, above the garage roof and clear of the power lines, for a good view.

I dashed inside to get eyepieces and mounting, but on emerging found that the neighbor's cat had jumped up on the porch railing to mooch his daily handout. Even with stopping to feed him, I had the telescope set up and pointed at the comet inside of five minutes.

It had been months since I had looked at Hale-Bopp with more aperture than 63 mm. I was anxious to see all the structure in the coma, that everyone has been talking about. Sure enough, even with just my 53x find-it-and-center-it eyepiece, I could see a jet in position angle 270 degrees and three 120-degree segments of concentric circles, spaced equally apart in radius, each spanning from position angle 150 to 270.

The view was similar at all the other magnifications I tried -- 88x, 150x, 250x, and 375x. The outermost arc was very faint; I could glimpse it only intermittently, with averted vision. The innermost was brightest, and merged with the jet at the 270-degree end. The arcs appeared to end fairly abruptly at both ends, perhaps more so at the 270-degree end.

The jet did not turn smoothly to join the innermost arc, rather, it emanated radially outward from the nucleus, then appeared to broaden and terminate as it intersected the arc, as though it had run into an obstruction. I also detected what I would describe as a slight "anti-jet" (possibly another jet -- I have no reason to think the two features were associated), a shorter and less bright streak emanating radially at position angle 90 degrees. I did not see any other jets.

The dust and ion tail were evident at the lower magnifications; I did not attempt to trace either with the Intes.

It is always fun setting up a telescope in a settled area. Everybody wants to know what you are doing. A young woman across the street brought her son to see the comet -- they were at a previous neighborhood star party, during the blackout after the '89 earthquake, when he was still too little to appreciate such things. Several passers-by stopped to look, first at the telescope, then through it. I spent time explaining what we were looking at, how big it was, how far away, how many millenia till the next chance to see it, and that no, I didn't know what all those funny arcs were about, either.

I dug out my 10x50 Ultraview binocular to let folks trace the tail, and tried it myself -- I could see dust tail out to five degrees, with some obvious linear streaking, but not much of the ion tail. With the naked eye, I could only see two or three degrees of tail.

Before going inside, I took a brief, dazzling look at the nearly full Moon. Even at only 88x, Schroter's Valley and the long narrow hills that nearly merge with it as it turns northwest, were prominent.

Another good night. I may have to put rails down my driveway so I can hold polar alignment as I move the telescope to peer around trees, but there is surely plenty of astronomy to be done from in town.