Hi all, Jeff recently asked about the radius of earth shadow , as cast on the geo arc , under perfect conditions. For my location , here in the UK , I should be able to get an accurate "guesstimate" ... if there is such a thing , by observing the track of earth shadow this evening....the peak of the eclipse/outage season for this latitude. However , as I seem to be clouded in again , its highly unlikely that I will get the opportunity. Looking at the video timings from the other night , I can see that the leading edge of the shadow was moving at a rate of one degree every 3.5 minutes or so , which is about right....and as the satellites at 28.5 degrees were coming out of eclipse , the birds at 16 east were just entering. So , this gives a shadow diameter of 12.5 degrees. Converting this to km , I get a figure of 9250km. I would expect this figure to be in excess of 12,800 km tonight , when everything is lined up . Does this seem right ? I'd appreciate any comments from more proficient math students ;O) The video has also revealed that the geos in orbit over Europe are now increasing in magnitude , just prior to eclipse , to a level of mag 8 or better , bringing them into bino range. This became apparent when I started to examine the dropped frames from friday's recordings. Regards, John. ------------------------------------------------------------------------- Subscribe/Unsubscribe info, Frequently Asked Questions, SeeSat-L archive: http://www.satobs.org/seesat/seesatindex.html
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