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Hi Derek, re: > Thanks. To answer your question, we will ultimately want to show satellite > positions superimposed over the GOES imagery, so the more recent the > imagery, the more "real time" is the display. OK. The _great_ majority of the coverage in the composites is from geostationary satellites. Given that the international agreement that geostationary satellites' positions be maintained in longitude to within 1 degree, the variation in location of the satellites will not be noticeable on a display (they will look like they are fixed). re: > In essence, if the GOES > imagery is a day old, then the current satellite positions are not in syn > with the imagery. It sounds like you are referring to polar orbiting satellites, not geostationary ones. And, the geostationary satellite portion of the composites will mostly be in the same hour as the composite's nominal time. Polar orbiter portions of the composites could be up to 2 or three hours old, but this is not a fixed number. re: > As you note, this is for outreach and not for scientific > operations, but it's our goal to try as best we can. OK. re: > So, if I understand you correctly, the image that I upload each three hours > will be a myriad of scans from varying times. Correct. re: > So, if I can give my > supervisor an average latency-- let's say, for each three hour upload, the > imagery would be on average no more than about 6 hours old-- that would > satisfy his concern. I think that the maxim difference in time of any component from the nominal time should be less than 3 hours. There is _no_ guarantee that this will always be true, however. re: > If, on the other had, the images we upload every three > hours could be as much as one day old, he will want to know that. This should never be the case. re: > Obviously, there will times when the satellite scans are bad or delayed, but > just an average and a worst case would be sufficient. See above. re: > Anyhow, I hope that helps, and clarifies the reason for that concern. And > again, I appreciate your time and thanks for uploading the CentOS. No worries. I'm still at home, but I will be heading in to work in about a half hour. Given my drive, I should be uploading the VM by noon our time. Cheers, Tom -- **************************************************************************** Unidata User Support UCAR Unidata Program (303) 497-8642 P.O. Box 3000 address@hidden Boulder, CO 80307 ---------------------------------------------------------------------------- Unidata HomePage http://www.unidata.ucar.edu **************************************************************************** Ticket Details =================== Ticket ID: UFF-250801 Department: Support McIDAS Priority: Normal Status: Closed