Posted 21 March 2012 - 05:45 PM

Whoops, here is a second e-mail from Richard McKim:"Dear Jim:Thank you. In fact I misunderstood your ......-18LTL image, as I was looking more at the large light area you had artificially highlighted rather than the terminator projection. Before your blue image arrived on its own I had assumed, from quickly reading, that the artificial area was the new feature! It is all perfectly reasonable-looking now that I have your blue image and, although we don't see much phase visually yet there will be a slight and growing phase defect on the following side.Although quite evident the projection is no doubt standing out even more because the processing of any image has caused the terminator to darker somewhat (and in the case of Venus to recede) to leave the projection more visible. There is a history of high latitude martian projections. I am thinking of certain HST images from the 1990s, and visual observers have certainly detected many, and I can recall quite a few examples even in my own Mars reports. I don't think our amateur images were good enough to catch them before 2003. I have examples in the 2003 BAA Mars report which is posted as a pdf at www.britastro.org \mars...............This particular one you have caught so nicely is certainly on the large side, and I hope you will get the chance to repeat the observation at the same CM over several nights. And that brings me to ask if you can compute the CM and put it on each image because it does save looking it up. From the position of Propontis with regard to the morning terminator I would say that the attached image by Efrain Morales is really pretty similar to yours in CM but is dated two days earlier (March 19d 02h 31m UT). I notice that he shows the same effect but it is less visible. It is easily missed unless one enlarges the image.I will of course search for others. I receive a lot of material which is not uploaded to any of the image archiving websites.Let me know what you think.I am off to bed as it is getting late here and I must teach first thing in the morning!With regardsRichard"