Occultation by (364) Isara observed from Martel, Ohio
The actual path was about 1.1 path-width (= 1 sigma of Preston's path uncertainty) south of the predicted path
So far, there are no positive observations of the occultation of a faint star by (135) Hertha a few hours earlier
new: 2006 May 30
So far, I've received three observations of last night's Hertha appulse with a 12th-mag. star in Cancer east of the Praesepe & Saturn, all negative, including mine at about +28 km near Imler, Penn. I tried to go to n.w. Penn., but ran into a lot of clouds around Somerset, and my direct observation and consultation with the National Weather Service indicated central Penn. would be clearer than the I-79 & Ohio/Penn border area. So I backtracked to Bedford, then went northeast on I-99. I also set up a remote station to record the Hertha event about 7 miles south of Altoona, but I'm sure that failed because that telescope was out of collimation (so the images were poorly focused) and it didn't have an image intensifier. Derek Breit mentions that Tammy Plotner observed the occultation by Isara, the only positive observation of that so far. His message giving her observational data is below. The 9.7-mag. star was SAO 140367 = TYC 55840062 (or TYC 5584-00062-1 in full), a few deg. from beta Librae. A list of the coverage we had for the occultation as far as I know, using "old" distances (in km, 1st col.) consistent with Preston's April 29th prediction: +45 negative, Rob Walker, mobile near Topeka, IN +32 negative, Paul Maley, mobile near Chardon, OH -12 negative, Phil Plante, Mahoning Valley AS Obs., n.of Newton Falls, OH -24 flubbed it, D. Dunham, n. of Waterville, PA (see below) -65 positive, Tammy Plotner, Martel, OH -99 light pollution too strong, Ken Coles, Indiana, PA Plotner's observation indicates that the path shifted south by probably more than a path-width, perhaps a 1-sigma (1.1 path width) south shift. So the path passed more over central Pennsylvania than northern Penn. as expected. It's too bad that the two closest observers to Plotner both failed to get an observation, although if Plotner had a nearly central event, then it's likely that both of us would have had a miss. Plotner's information, from Derek Breit, is below, followed by my sad story. Tammy Plotner observed her first asteroid event with the Isara occultation. She had a 1.9 second event. Start and Stop times not known, as she is not yet set up to do these events.. Position: Martel, OH, long. -82.91 deg., lat. +40.67, h 1000 ft. Tammy Wrote, "thanks for the heads up and the accurate positions! this was actually rather fun since I didn't have to work the next morning. it would be very cool indeed if we had an event that would be visible from the Warren Rupp Observatory some time that we could record with the Stella cam and the 31"." _________________________ For me, it was a frustrating case of defeat snapped from the jaws of victory. After Hertha, I was far west of where I wanted to be (closer to the intersection of the predicted Hertha & Isara paths near Cleveland, OH) so I had to drive a considerable distance to get to Isara. And the roads in central Penn. mostly follow the s.w. to n.e.-trending mountains with only slow, winding mountain roads going north. So I drove n.e. as far as I could, not taking time to know where the path really was in north-central Penn., but knowing it was in the farther northern part of Penn. I hoped to get to Williamsport, then drive north on US 15, a good highway that bucks the trend and does go almost due north. But by the time I approached Williamsport, it was clear I would get there too late, so I exited US 220 at Avis and drove north on Hwy. 44 into the mountains, thinking I had to get farther north. I wanted to be near -40 to -30, but ended up farther north than intended, at -24. The sky in the mountain valley was one of the best I've ever seen from the eastern US, with a nice dark sky and the Milky Way so bright it looked almost like approaching storm clouds. But I arrived there about 30 min. before the event, when I need 40 min. to comfortably set up & locate the target star. By the time I correlated the finder view around beta Librae with the star charts and located the target star, it was several minutes too late. The star was quite bright with my image-intensified view & 8-in. SCT. If I had stopped driving earlier, I would have been farther south, more likely within the path, and would have had time to get on the target star before the occultation. I should have taken the time to figure out where the path was, to get to my intended line, like I had done for Hertha (for that, I had my laptop with me and rather than take the time to get a GPS reading, I just entered approximate coordinates, to about 0.3', obtained from the Pennsylvania Delorme Atlas/Gazetteer, into a small multiloc file to run with the Occult program, already having the Hertha & Isara occelmnt files from Preston's Web site on my laptop that I had used for calculations for the messages that I distributed before leaving home). Pre-event predictions and plans for the three Memorial Day Weekend asteroidal occultations is here. So far, I only know of one observation, negative, of Sat. evening's occultation by (540) Rosamunde, by Roger Harvey from his observatory in Concord, NC, rather far south of the predicted path for that event. David Dunham