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Another point to be considered in creating charts for variables- Be aware of the previously existing sequences for a particular star and the ramifications of wholesale changes to the sequences on the historical data. Of course, adding this to the list of "qualifications" for accredited chart makers narrows the list of potential candidates to a select few, who are probably professional astronomers that would have little or no interest in such a job. That is why much of this work has fallen to dedicated amateurs. (I've always thought the charts for visual use should be made and checked by experienced visual observers, which would eliminate most professional astronomers too.) For the most part, chart makers have done an admirable job with the information available. The charts served the needs of most observers with modest equipment, and a lot of good work has been done using them. However, we have now come to a point where the needs and equipment of serious amateur observers has far outstripped the utility of the more antiquated charts. Most of the telescopic sequences only reach into the 13th or 14th magnitude, while many of us routinely observe stars visually in the 15's and 16's. And the accuracy of 14th mag comps based on pv magnitudes is suspect at best. The majority of these charts are nearly useless for CCD observers, mainly because they were never intended to be used for this, so they do not match the needs or potential accuracy of CCD observers. Most have not even been updated with accurate magnitude information for the bright end of the sequences where good photometry does exist. Unfortunately, little significant improvement will ever be made until there is an accurate source of magnitude and color information for the whole sky down to at least mag 16, and investing the time and money to rectify the chart situation is deemed a priority. Mike
Return to the Powerful Daisaku Nogami
vsnet-adm@kusastro.kyoto-u.ac.jp
