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Re: [vsnet-chat 6066] NMO Campaign > For many stars there is not enough data to make reliable predictions or > create light curves demonstrating the behavior of these stars. These stars > are listed in a supplement to the Bulletin, "Stars in Need of More > Observations". > > [...] > > We encourage visual observers to obtain positive estimates of the stars > brighter than 13.5V first, and then move on to other targets. CCD observers > and visual observers with large aperture scopes are encouraged to go after > the objects fainter than 13.5V. Any observations of stars with old or no > data are useful. It would be worth mentioning that almost all (or even more) stars can be detected with an unfiltered (or with Rc or Ic filters if one would like standard passbands) CCD camera with a telephoto lens. This is partly because "faint Mira stars" on visual program are often a selection of "visually faint" stars, such as carbon stars or reddened (eith by circumstellar or interstellar dust) objects. These objects are usually conspicuously detected on unfiltered CCDs. The "faint Mira stars" list can thus intrinsically be strongly biased, and may not represent a representative selection of the Mira population. So, my suggestion is to monthly get CCD photometry with a wide-field camera. A weekly basis would be preferrable. With such equipment, almost all bright Mira stars will have sufficient coverage to make ephemerides. Of course, there is no neccesity for maximum predictions for this type of observation, though... There was a good example of such coverage by the MISAO project a few years ago. These observations reported to VSNET have illustrated the ability of wide-field CCD survey to record such poorly observed LPVs. The observations generally well agreed with visual observation with respect to the maximum determination. The only problem is that the time-consuming procedure for reporting by the MISAO project (or more correctly, the human neccesity to examine PIXY output) has disabled further reports. There must be a huge number of unreported, but meaningful, measurements left in the hard disk of Yoshida-san's computer... it might take a century for Yoshida-san to fully examine these results. The reported inaccuracy of the PIXY will not be a significant problem in determining these LPV light curves. The next step we would need is the way to make PIXY more numerically reliable and automatic in producing variable star reports. Implementation of a similar function in widely available programs will naturally be also very welcomed. Regards, Taichi Kato
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