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----- Original Message ----- From: "Taichi Kato" <tkato@kusastro.kyoto-u.ac.jp> > I sometimes wonder why we need more observations for poorly observed > long-period variables. I think this somehow needs to be justified > in terms of science. My understanding is that the main advantage of > visual observations of long-period variables are their long-term continuity, > with which a long-term period change can be determined. In long-period > variables, (short-term) intensive campaigns would be less productive than > in other variable stars. Even a ten-year baseline would mean ~20 cycles > for a P=180 d Mira star. Such a small cycle counts have been shown to be > inadequate to derive any period changes. The natural consequence is that > either (1) such campaigns need to endure for many decades or (2) such > campaigns should focus on long-period variables which have decades-long > sufficient and continous observations. Coming from Vsnet, an organization that has existed for only a few years, I guess it's difficult to understand that AAVSO *is* a decades-long observing campaign. AAVSO attempts to follow the activities of many stars. Some of them are not as well-observed as others; for as long as I have been around (only since 1982) there have been annual lists of stars that need more observations. These stars are not as frequently observed as the others for a variety of reasons, some to do with inadequate charts, poor sequences, or just plain difficult stars in crowded fields or with close, bright companions. Some just seem to be overlooked. Mike Simonsen, God bless him, has again perceived a need and jumped on it with both feet. His effort will help focus attention on these neglected LPVs. It's not intended to be a "short-term" intensive campaign on these stars, as I see it; it's intended to focus more observers on these stars and bring some needed attention to the charts for these stars. It's intended to mesh with the nearly one-hundred-year ongoing observing campaign of the AAVSO. As far as scientific justification for observing LPVs, I simply point to the variety of papers published using AAVSO data. A few minutes on ADS will turn up a bunch. I'm sure someone logging an observation of R Cen or R Hya almost a hundred years ago didn't know *precisely* what his observation would be used for, only that monitoring nature's behavior was an important activity. It still is today. Those in the game to grab a few observations of some star in order to dash off a quick paper in some journal in search of ephemeral glory don't understand the quiet beauty and inner peace that lies in the simple tasks of monitoring variable stars. I know that that observation of T Columbae I made last night is not going to rattle the universe, but I also know it will live on, and be useful to some future researcher, long after I'm gone. I can't predict what that star might do, but consider an oft-overlooked point of science: determining that a system doesn't change (over the time scale of the observation) is just as important as observing a rapidly changing system. It's not glamourous, but both describe what's happening in the universe. Finally, one of the things I most enjoy about AAVSO and variable stars is the sense of history involved. When I am observing LPVs, I am joining the ranks of some very notable individuals in astronomy. I am currently working on a couple of projects involving suspected variable stars. The original observations go back to E.E. Barnard, and the follow-up and discovery was published by Frank Ross in the late 1920s. I am truly standing on the shoulders of giants. I don't expect anyone to ever stand on *my* shoulders, but someone may stand on the database of variable star behavior that we are patiently building, decade by decade. I may contribute only 1% of what Mike Simonsen does, but I am here, and I am here for the long run, just like AAVSO. Jim Bedient Honolulu, Hawaii
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