From jop at astro.columbia.edu Wed Oct 10 10:30:56 2012 From: jop at astro.columbia.edu (Joe Patterson) Date: Wed, 10 Oct 2012 10:30:56 -0400 Subject: (cba:news) Fwd: SDSS1642+1347 In-Reply-To: References: Message-ID: <507586A0.90908@astro.columbia.edu> Hi CBAers, HST is about to observe this star, but is worried about its brightness (it has some small jumps up from its quiescence at V~18.3). As early as anyone can get it tonight, can you check? Just a quick check would be great. I doubt anyone can get to it by 1600 UT... but the sooner the better, especially if you're in Europe (or even farther east?) joe p.s. send to Boris.Gaensicke at warwick.ac.uk, and to me. Hi All, STScI would like an update on SDSS1642+1347 by ~16UT today. when the star is not easily visible for most of our observers. Any observations from Europe early this evening will be most welcome. Cheers, Boris -- You received this message because you are subscribed to the Google Groups "hst12870" group. To post to this group, send an email to hst12870 at googlegroups.com. To unsubscribe from this group, send email to hst12870+unsubscribe at googlegroups.com. For more options, visit https://groups.google.com/groups/opt_out. From jop at astro.columbia.edu Thu Oct 11 09:20:26 2012 From: jop at astro.columbia.edu (Joe Patterson) Date: Thu, 11 Oct 2012 09:20:26 -0400 Subject: (cba:news) sdss1642+1347, and some others Message-ID: <5076C79A.4060008@astro.columbia.edu> Thanks Enrique and Joe U, SDSS1642 was at quiescence yesterday, the HST safety people are placated, and the observation will start in about 1 day. Continued monitoring from now until the end of the observation (Oct 12 6:22 UT) is *extremely* desirable - for science, as well as for safety. The next 5 targets are: AX For RX0232-37 SDSS0011-0647 HS2214+2845 CC Scl Monitoring of these is now timely as well. Mainly snapshot magnitudes... but in case anyone can get time-series on RX0232-37, that would be great! I consider it one of the most fascinating CVs in the sky, but with quiescence quite faint (18.5-19), it usually doesn't make our lists. And apart from HST issues... Many of you contributed heroically to our campaigns on BK Lyn and ER UMa in 2012. I think the papers being readied now on these stars will have a great impact on CV science, especially CV evolution... and will certainly have a great impact on our observing programs. In particular, the ER UMa class. It's a small class and we should study all of 'em over the next year (BK Lyn, ER UMa, RZ LMi, V1159 Ori, MN Dra, DI UMa, IX Dra, V503 Cyg). Most are somewhat out of season, but: (1) V1159 Ori is pretty well placed (plus it's so close to M42 that you get to glance at that every night); and (2) *short* coverage, or even snapshot coverage, is quite desirable for these stars; their rapid up-and-down hijinks are very definitely of interest - and so far, what make these stars so mysterious. From the 2012 coverage of BK Lyn, I think we've learned now that the timescale for a short-Porb classical nova to decline to quiescence is not 30-50 years, as usually assumed, but at least 10000 years. (No typo here.) This greatly affects our ideas of CV evolution, as well as of novae. I expect to finish this paper around November 1, with all the CBA BK Lyn observers (since 1999!) as co-authors of course. So: 1. If you've observed BK Lyn for us anytime since 1999, send me your current postal address and email; and 2. I apologize for taking 13 years to write the damn paper! Some of you occasionally give talks at your local astronomy clubs. This could be a very interesting subject, if you're inclined to take it on. Helena and I will be talking about the star, and these ideas, at the Cape Town nova conference in February. We'll have some good slides to contribute, and of course the fireworks of novae are a natural subject for public talks anyway. joe From jop at astro.columbia.edu Tue Oct 23 11:40:38 2012 From: jop at astro.columbia.edu (Joe Patterson) Date: Tue, 23 Oct 2012 11:40:38 -0400 Subject: (cba:news) Fwd: 1RXS-J023238.8-371812 In-Reply-To: References: Message-ID: <5086BA76.8060809@astro.columbia.edu> Hi CBAers, Here's the next star on the HST menu - RX0232-37. This one is not only relevant to the forthcoming HST spectrum - it's also an absolute primo CBA target (or would be if it were a tad brighter). So time series would be very, very valuable. At 18.5, it'll be a stretch; but my guess is that this is a very, very ancient CV - older than WZ Sge, even. Just knowing Porb would test this hypothesis very strongly! joe Hi All, in particular Arne & Joe, > the second visit is now scheduled, 1RXS-J023238.8-371812: > > Nov 1, 2012 22:52:28 Nov 2, 2012 07:09:06 NB to this: I feel much more relaxed about this one, as it should not show much activity - but of course STScI require the usual intense monitoring. The data we have far, http://www.aavso.org/lcg/plot?auid=000-BCY-373&lastdays=50&obstotals=yes&calendar=calendar&grid=on&visual=on&uband=on&bband=on&v=on&pointsize=1&width=800&height=450 is re-assuring, but it would really be great if we get a few more southern observers involved until Nov. 1 - could you send out another alert / request for help? Thanks, Boris -- You received this message because you are subscribed to the Google Groups "hst12870" group. To post to this group, send an email to hst12870 at googlegroups.com. To unsubscribe from this group, send email to hst12870+unsubscribe at googlegroups.com. 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