From jop at astro.columbia.edu Thu Sep 6 10:21:44 2001 From: jop at astro.columbia.edu (Joe Patterson) Date: Thu, 6 Sep 2001 10:21:44 -0400 (EDT) Subject: (cba:news) WZ Sge and September stars Message-ID: Dear CBAers, WZ Sge continues to bump along up there between magnitude 11 and 12, with these little "echo outbursts" that are so puzzling. At ~1.5 day intervals, and 9 of them so far! Getting awfully hard to track the damn thing. Sure would be nice if someone knew what they are. Many of the heroes of August are taking a rest now. Michael Richmond has resumed teaching (hardly a rest, ha!), and Gianluca Masi is taking some well-deserved R&R. Tonny Vanmunster cleverly took his vacation when the star erupted, so is now enslaved to the star for the decline. The New Zealanders may be getting grumpy about observing northern stars. Donn Starkey and Brian Martin are still keeping the faith, getting long runs as weather permits. Lew Cook stubbornly refuses to quit his job and observe every night, but rules the weekend nights. Arne Henden is resting somewhere near Flagstaff (excellent choice). Anyway, we do need some new heroes! Or the return of well-rested old ones. Jonathan starts a new observing run on the 1.3 m tonight for 11 nights, when we hope to do a good job defining the eclipse phase (especially). Since WZ Sge has 2 other competitors for time (KL Dra and GD 552), we hope to rely on CBAers around the Earth to provide the long coverage needed to specify the periodic clocks (orbit, superhump, whatever). It would help us to know your observing plans, as we juggle priorities. Jonathan's email and phone at the observatory are jk at cbastro.org and 520-318-8661. We've still not put up a WZ Sge webpage, because individual CBAers have better ones that we can make - instead I've worked hard on the scientific analysis, trying to cope with all the complexity WZ Sge has flung at us. I expect to get something slapped together by mid-fall (classes have started here too). So the stars of the month are still WZ Sge (both hemispheres - I hope!), AO Psc (both), FO Aqr (both), V709 Cas (north), V1223 Sgr (south). And KL Dra (very difficult) and GD 552 = Cep 1 for people who love those far-northern guys. Have a great old time observing. What amazing intricacies WZ Sge is hurling at us this year! I only hope we can figure 'em out. joe From jop at astro.columbia.edu Mon Sep 10 18:25:58 2001 From: jop at astro.columbia.edu (Joe Patterson) Date: Mon, 10 Sep 2001 18:25:58 -0400 (EDT) Subject: (cba:news) Tonight, tonight... Message-ID: ... won't be just a-n-y night... As the song should have said, it's a night of HST observation of WZ Sagittae. So aside from the high interest in following the star anytime during this month, tonight's observations will be accompanied by simultaneous space data - ultraviolet spectroscopy. All the more reason to get thee to a telescope! Jonathan's doing very well with Arizona observations. Lotta clear weather. So far no help from observatories far to the east and west... but who knows what riches may still be in the pipeline? If you can obtain time series anytime during the next 10 days, especially in Europe/Asia/AU/NZ, this is the hour of need! joe From jop at astro.columbia.edu Wed Sep 12 08:21:34 2001 From: jop at astro.columbia.edu (Joe Patterson) Date: Wed, 12 Sep 2001 08:21:34 -0400 (EDT) Subject: (cba:news) news from New York Message-ID: Dear CBAers, Many thanks to those of you who wrote to express their concern, and for thinking about us. For those of you who don't know New York City, there is a "downtown" part where all the tall buildings live, and an "uptown" part where people tend to live. Since 1903, Columbia has been uptown, 6 miles north of the World Trade Center. A steady breeze blew from the west yesterday, so the great pillars of smoke blew straight east, away from us. There was no damage at all near the University. As afternoon came, great lines of cars appeared, heading north away from the area of attacks. Barely moving; the biggest traffic jam I ever saw. Many people walking too, but very orderly. The food stores were jammed. By late evening the streets became very quiet, with cars practically gone but student life seeming normal. As far as I know, no one from our community was caught near the WTC yesterday. We watched from the roof and from TV, like everyone. This morning there were many grieving people on the streets around Columbia. As some of you know, the WTC has little involvement with some sectors of NY (academic) and close involvement with others (trade, finance, tourism, government offices). But the neighborhood is eclectic, so some people must have had great losses. I saw many black people crying on the streets as I walked to work this morning. Maybe the human pattern is: first day shock, second day grief. I think I remember reading that, and it accords with my own meager experience. Jonathan is fine, observing on Kitt Peak. It's calming to think that the cosmos is undisturbed - WZ Sge flaring again - and it's more than calming to think that I can come to work and focus, however briefly, on these celestial puzzles that fascinate us all so much. I'm deeply grateful for all your wonderful observations! joe From jop at astro.columbia.edu Fri Sep 28 12:53:18 2001 From: jop at astro.columbia.edu (Joe Patterson) Date: Fri, 28 Sep 2001 12:53:18 -0400 (EDT) Subject: (cba:news) Southern stars, and WZ Sge Message-ID: Dear CBAers, As most of you know, WZ Sge has probably settled into its final decline now. (Actually, it'll probably have about thirty million more final declines in the next Gyr - but with our characteristically parochial viewpoint, humans like to call it final.) It's at V=13.8 and slowly fading. Slightly harder to observe now because of the onrushing western horizon, and the possibly obstreperous companion. Thanks to all your efforts - and thanks to the serendipidity of a *July* eruption! - we definitely have the most exquisite photometric record ever of a dwarf nova in superoutburst. I am having a grand old time marvelling at the intricate periodic structure of these humps. To my delight, we've done at least as good a job exploring that intricate structure as we did on AM CVn 2 years ago. I didn't think we ever could for a dwarf nova - they tend to not stand still long enough to permit very accurate measurement. WZ Sge didn't stand any more still than any other star, but because of observer tenacity - and in part because of the Halley's Comet-like publicity machine that the star enjoys - we made up for it. I expect to get the paper sent off in another 4-6 weeks. In a few days we hope to get the observing log posted on the web; that'll enable you to check whether all your submitted data got through OK (in addition to the electronic thanks). Although the outburst is mostly over, we'd like to keep coverage alive for about 3 more weeks. The superhump, you see, is still going strong. As usually happens in the best-observed stars, the superhump greatly outlives the outburst that spawned it. A feature of dwarf novae not yet understood, and we hope to make progress on it by watching our superhump slowly die over the next few weeks. So the best object for NORTHERN COVERAGE is still WZ Sagittae. Stay motivated! The backups are the DQ Hers: FO Aqr, AO Psc, V709 Cas. But of course... if GD 552 = Cep 1 erupts, then quit your job, sell everything you have and give to the poor (except your telescope and computer), and dedicate your life to the star. V1251 Cyg too, but not as extreme (do consider quitting your job, however). Southerners gave up on WZ Sge a long time ago, murmur, murmur. Bob Rea, Fred Velthuis, and Jennie McCormick have been doing a good job dodging NZ clouds and hitting V1223 Sgr and FO Aqr. But it's a good time to switch southern stars. There are THREE new southern stars deserving of center stage. The first is BW Scl = RXJ2353.0-3852. Mag 16.5, we'll be studying it intensively from Chile next month. Probably a dwarf nova, though no eruptions ever observed. 23 53 00.70 -38 51 45.6. Strong waves in the light curve, let's explore 'em! If that star's too faint, then I recommend EC23593-6724, a 14.3 mag star at (1950 coords 23 59 21.7 -67 24 28) which is a short-period CV of unknown type. Another star we plan to observe from Chile. Finally there's EC05114-7955, a 15 mag star with P near 3 hr. Lots of cool photometric activity, very friendly dec, many things left to learn! (Practically everything.) 1950 coords 05 11 25.1 -79 55 02. So let's see what the cats can drag in! joe