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Re: NMO Campaign (This is not a query to Janet herself, but I would like to know the thoughts by other variable star observers/researchers). > It is great to see the interest to observe Long Period Variables > (LPVs) and particularly those that need more observations. 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. I wonder whether the individual objects in the current campaigns satisfy either of these conditions. [NB. Conditions would be different in other classes of variable stars. There would be a small possibility that any Mira star would experience an unpredictable phenomenon, but the probability of such a phenomenon would not be different between well-observed and less-observed stars]. I raise this question because of potentially expected side-effects of this kind of systematic "need more observation" campaigns, but have no intention to discourage the efforts. I have seen in several circumstances that affected people started different "need more observation" or "faint object" campaigns. They indeed produced some observations, caught some maxima of some obscure long-period variables, but many of them lost interest after one or few cycles. I don't say these observations were meaningless, but there might have been a different strategy for inspiring observers. In actuality, almost all variable stars are in need of observations and discontonuance of the existing observations can be fatal. Even considering these circumstances, we probably need a modern discipline for promoting variable star observations in the era of wide availablity of various observing modalities. Regards, Taichi Kato
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