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> The bright star marked var? south of RS Oph on Sebastian's chart (AAVSO 93) > is not likely variable and should be retained as a comparison. The > measurements from ASAS 3, Tycho and Henden (recent) all agree. > > Tycho-2 9.34V, B-V 1.22 > Henden 9.319V, B-V 1.171 > ASAS-3 data is 9.31V. > > The source of concern on Otero's part was from his use of the magnitudes in > Arne's original data, which is saturated at this level and therefore > unreliable. > > Needless to say, anyone lucky enough to use this comparison in making an > estimate or measure will be witnessing something special! I wish I could use it! Anyway, let me clarify that my concern regarding variability of HD 162215 wasn't based on Arne's previous deeper data (I supposed it could be a saturated measure) but in a V measure in the GCPD: V= 9.68, B-V= 1.266. This is from Connelley M., and Sandage A., Photoelectric observations of RS Ophiuchi, 1978, PASP 70, 600. Arne's measure gained another meaning after I saw that measure.... But.... ASAS-3 data don't support variability. And now Arne has obtained a consistent result with Tycho-2 and ASAS-3, so... I think it could be used as a comparison star as Mike suggested. Of course, now the charts are issued, an eclipse or something will happen ;-)) BTW it is a single-lined spectroscopic binary (Latham, 2002). > As mentioned elsewhere, there is a typo in the declination for RS Oph on > Otero's chart. > It should be -06 42 28.6 not -06 42 18.6. Fixed ;-) > The recent reported brightening of RS Oph does seem to be real. Henden's > most recent observation (of unknown specific date UT, sorry) is 10.759V, B-V > 1.108 with errors expected to be +/-0.003. > > Whether or not RS Oph is ready to impress us again is yet to be seen. But I > seem to recall WZ Sge was a little earlier than expected this time around, > so you never know, do you? That is what makes this so much fun. > > There seems to be some discrepancy as to whether RS Oph is a NRa or NRb > between GCVS and Webbink's paper. Any comments/clarification on this would > be most welcome. The GCVS team simply didn't use the distinction between thermonuclear runaway events (NRa) or disk instability events (NRb). That would be a useful thing to add in a future release. RS Oph is an NRb. > There is a very good article on RS Oph by Kerri Malatesta, in the Variable > Star of the Month archives at AAVSO > http://vsnet.aavso.org/vstar/vsotm/0500.stm A great piece of work. I think VSOTM is a great contribution for the field from AAVSO. Congrats! Sebastian.
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