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Fellow observers, The following is a summary of discussions by members of the NMO email discussion group in recent weeks, and comments from the AAVSO Director. General discussions: Some stars are giving less experienced observers problems. The email group has proved to be an informal tutoring and support group for all involved. Discussions regarding U Lyn led us to find that some NMO observers had mis-identified U Lyn. After re-examining the field using DSS image charts, it became apparent that some of us had mis-identified a close companion as the variable. Corrections have been sent to HQ deleting the erroneous observations. We made an effort to coordinate observing specific stars or constellations to try to assure better coverage of stars going into conjunction and morning objects, but were foiled by the weather and full moon. This also led to a rather lively discussion of the effects of weather and the moon on observing. Occasionally we find, through comments made by observers, that they are using old charts or charts that don't go deep enough to identify and estimate the variable. It is up to each observer to make sure they are using the most recent and the best scale charts to observe these stars, especially since improvements and updates are being made. To keep up with the changes made it is recommended observers check the AAVSO chart updates page and sign up for the charts announce email list at http://charts.aavso.org/updates.stm Availability of reverse charts is an issue for observers using SCTs or refractors. Several members of the group have made reverse charts for stars not currently available from AAVSO. AAVSO is working towards making these reverse charts available online. Please check the updates page for the latest additions. Although the initial effort of the NMO observers was concentrated on northern targets, several members living in more southerly latitudes are sharing notes on stars they are observing below -15 declination. Releasing the NMO Planning Tool which now covers the entire list of "Needs More Observation" stars from Bulletin 66 should prove useful to these and other southern observers. It is now available online at http://vsnet.aavso.org/bulletin/ The original list of northern targets will still be posted to the Sirius Astronomy pages monthly at http://home.earthlink.net/~joevp/nmo.html Members of the group also shared new files containing _all_ the stars in Bulletin 66 as an Excel spreadsheet sorted alphanumerically by constellation. This will soon be made available online at http://vsnet.aavso.org/bulletin/ Special thanks to Marc Biesmans for the text file and Geoff Gaherty for the Excel spreadsheet. Specific chart issues: It was determined that the coordinates for Y Ori, RU Lyn, U Lyn and BF Cep were in error on the AAVSO charts. These have all been remedied and new charts posted. Again we remind observers that they can sign up for email notification of chart updates at the AAVSO website. Several charts are of such poor quality that they make observing the stars difficult. UY Gem- the d chart does not indicate the position of the variable accurately and the sequence is inadequate to cover the faint end. The e charts are somewhat better and do have a more complete sequence. CD Gem, VV Her, AZ Her and V450 Oph charts are sloppy or crowded and difficult to use in locating and/or estimating the stars regardless of the observers experience or telescope. Exercise caution when using these bad charts. CCD discussions: Several CCD images of TZ Tau have been posted by observers and none of them show a faint close companion to the variable. We believe the companion indicated on the AAVSO charts does not exist. Field calibration for TZ Tau will be forthcoming from CCD observer Tim Hager. Tim also submitted preliminary findings on the field of UY Gem. At this point we can say the 132 comp is quite red and should probably not be used, and the 122 comp is a close double star. We anticipate seeing Henden photometry for ST Mon in the near future also. It was suggested that rather than waiting for a full blown calibration for some fields, an intermediate stage of quick calibration would get everyone on the same system, followed later by a careful calibrations as time permits. This strategy has the advantage of confirming which sequences are good or bad and most of the improvements can be made with little effort. In conversation with the Director today it was agreed that we will put this information to use to improve the charts for these and other stars as quickly as time and manpower allow. In the meantime, if you are reporting observations using non-AAVSO charts or sequences please indicate this with the letter K in the comments code section of your reports. My personal thanks to Janet Mattei for supporting this initiative and providing space on the AAVSO website for the NMO Planning Tool and other observing aids. Together we are working on improving the state of the charts for many of these stars to make observing them more fun and scientifically useful. Observers planning to submit observations of stars in the "Needs More Observation" list who would like to be included in the recipients list for these informal email discussions can do so by contacting me at mikesimonsen@mindspring.com Mike Simonsen (SXN)
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