Bob Clark posted: > This seems to be saying to me there could still be some U.S. > surveillance satellites that have not been revealed. Then > possibly there could be satellites with the very high > resolution I was speculating about. I can see how the following excerpt could create that impression: http://www.space.com/news/060707_graves_web.html "We have discussed the Graves results with our American colleagues and highlighted the discrepancies between what we have found and what is published by the U.S. Space Surveillance Network," said one French defense official responsible for the Graves operation. "They told us, 'If we have not published it in our catalogue, then it does not exist.' So I guess we have been tracking objects that do not exist. I can tell you that some of these non-existent objects have solar arrays. Col. Yves Blin, deputy head of the space division at the French joint defense staff, said France would wait until it had acquired, with the help of the German radar, further information about the 20 to 30 secret satellites in question before beginning serious negotiations with the United States on a common approach for publishing satellite orbit information." I detect a good deal of hyperbole and posturing, which can be discounted with a knowledge of what is, and is not, in the official U.S. satellite catalogue. The catalogue lists the more 31,600 objects tracked by the U.S. since the beginning of the space age. It has received sufficient independent scrutiny to state with confidence that virtually all launches to orbit have been accounted for. I recall (vaguely) that there may be one or two controversies regarding launches that may have reached orbit in the early years of space flight, but may not have been catalogued, but nothing in recent history. That said, the claim attributed to the U.S., "If we have not published it in our catalogue, then it does not exist", is hyperbole. U.S. sensors cannot detect objects in LEO less than several centimetres in size, so there must be millions of tiny objects, almost exclusively debris, that cannot be catalogued. There are also many pieces of debris sufficiently large to track, but which cannot be confidently matched to a specific parent object or launch, so they are not included in the public catalogue. Also, a number of old payloads have been lost for years at a time; however, these have been mainly small objects in high orbits. Recent advances in sensor technology has enabled many such lost objects to be found, and their catalogue entries updated. Apart from the understandable lack of data on small debris, and some long-lost objects, how can we reconcile the claim that Graves (which tracks LEO objects) is tracking 20 to 30 objects not found in the catalogue, some of which have solar arrays? The answer is that the U.S. catalogue omits orbital data for hundreds of U.S. (and a few Japanese) military and intelligence satellites. There are entries for those objects in the catalogue, giving their catalogue number, international designation, a pseudo name, date of launch, and not much else; in place of the orbital data and RCS value, is the phrase, "NO ELEMENTS AVAILABLE". So the challenge for non-U.S. satellite trackers, like the French Graves, or hobbyists, is to independently identify the objects that we detect and track. The current list of hobbyist tracked objects numbers about 185. We have identified all 106 that are in LEO and MEO, despite their "NO ELEMENTS AVAILABLE" status in the official U.S. catalogue. We have also identified quite a few of the remaining 79 objects we track, which are in high orbits. If France will publish orbital elements from its Graves system, I would expect to find, most (if not all) of the 20 to 30 that they cannot identify, among our 106 LEO and MEO objects, all of which we have identified. It is not that we are more intelligent than the Graves analysts; it is just that we have been doing this far longer than they have. The U.S. began to withhold orbital data on most of its military and intelligence satellites in June of 1983, and hobbyist efforts to keep track of those objects (and those subsequently launched), began almost immediately, and reached its present level of capability years before the development of Graves. Ted Molczan ------------------------------------------------------------------------- Subscribe/Unsubscribe info, Frequently Asked Questions, SeeSat-L archive: http://www.satobs.org/seesat/seesatindex.html
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