Ed, As you point out, the list on Chip's site is probably based on the list on CelesTrak at http://celestrak.com/NORAD/elements/visual.txt (although that list does not contain magnitude information). That list was created at the request of Jay Respler, but I really haven't received any suggested additions or deletions for some time. I am certainly willing to take inputs from anyone on this list as to how to update that list. Just let me know if I can help. - TS Dr. T.S. Kelso CelesTrak, http://celestrak.com E-Mail: TS.Kelso@celestrak.com Ed Cannon wrote: > Bob King wrote: > > "I'm writing about the easiest satellites to see > with the naked eye and would like the list's help > on what you think are the brightest 10 or so out > there after the space shuttle and space station. > These satellites should be in high inclinations > so they're visible most places around the world." > > Well, first, I suggest including Iridium flares, > since they are near-polar inclination and > predictable and just about the brightest > satellite phenomena of all. (However, if they > are not flaring, Iridium payloads are faint.) > > Beyond that, if you mean just payloads and not > spent launch vehicles, etc., for sure four of > the brightest payloads (after ISS and HST) are > the (classified) Lacrosses: > > 21147, 91-017A - Lacrosse 2 > 25017, 97-064A - Lacrosse 3 > 26473, 00-047A - Lacrosse 4 > 28646, 05-016A - Lacrosse 5 > > Lacrosse 5 sometimes does a disappearing act on > a pass. > > The three big (classified) Keyhole payloads are > sometimes very bright (but often faint). > > 24680, 96-072A - USA 129 > 26934, 01-044A - USA 161 > 28888, 05-042A - USA 186 > > In fact, many payloads in sun-synchronous orbits > can be very bright at times, but you just have > to be lucky or figure out how to predict when > they will be bright. Envisat is one of these. > In our summer here at latitude 30 north, in the > evenings there are quite a few sun-synch objects > that will flare very brightly in the vicinity of > the Big Dipper, or at least in the northwest. > > A couple of objects that are very interesting > because when they are brightest they sparkle > are USA 32 and USA 81. When they do this, they > are fantastic when observed with magnification. > >From latitude 30 north at least, they generally > do their naked-eye sparkling relatively near > to the highest point in a pass (culmination). > > 19460, 88-078A - USA 32 > 21949, 92-023A - USA 81 > > If you run predictions from day to day, there > are from time to time objects that will go over > at low height and range and so are quite bright > on those passes (given a good phase angle). > The Russians have a very large low-height > object in orbit from time to time that is under > 200 miles. I can't recall what they are called, > but usually they are in orbit for only four > months or so. > > Now, if you include spent launch vehicles, then > most Zenit vehicles (Russian, SL-16) and many > Long Marches (Chinese, Chang Zheng or CZ or LM) > are quite bright as long as you don't have bad > luck. (Bad luck is when they are pointing at > you, so that you don't get a good reflection.) > > The oldest easily visible object is 00694, > 63-047A, Atlas Centaur 2, but it's in a > low-inclination orbit and also due to tumbling > slowly is very faint about half the time. It's > in an eccentric orbit and so can be seen at > times from higher latitudes, but of course > isn't as bright then since it's farther away. > That's also true of the Milstar 3 Centaur > (25724, 99-023A) which after 11 years is still > tumbling every couple of seconds or so. > > Sometimes the OAO 1, 2, and 3 launch vehicles, > which I believe are Atlas Centaurs, do very > bright passes (but sometimes very faint, so > that I wonder if they are tumbling very slowly). > > The list that Ralph referenced used to be > maintained, by Jay Respler I believe, but as > Russell pointed out is now out-of-date due to > not including any recent objects. (This is > somewhat like my list of flashing geosynchs, > which I have failed to update for a few years.) > > Rainer Kracht used to maintain a list of > 40 to 50 brightest objects, but that's another > list that we don't have anymore. > > If you go to Mike McCants' website and get > his MCNAMES file (mcnames.zip) from this page: > > http://www.io.com/~mmccants/tles/index.html > > then you can, using Excel or something like > that, manipulate the file so as to sort it > on the fourth column of numbers, which is > the intrinsic magnitude. The brightest ones > are magnitude 3.5 or brighter. ("V" means > visually observed and "d" means theoretically > derived magnitude.) Of course you need to > know their orbits also, for your purposes. > Centaurs are intrinsically bright but are > 10th magnitude in geosynch orbits! So you > want only ones in low orbits. You can use > his Quicksat magnitude file in the same way. > It's qsmag.zip on this page: > > http://www.io.com/~mmccants/programs/index.html > > It at least identifies geosynchs and eccentric > orbit objects with "g" and "h" flags, so that > you can exclude those. (And the "d" flag is > for ones no longer in orbit.) > > Hope that helps some. > > Ed Cannon - Austin, Texas, USA > > > > > _______________________________________________ > Seesat-l mailing list > http://mailman.satobs.org/mailman/listinfo/seesat-l > > _______________________________________________ Seesat-l mailing list http://mailman.satobs.org/mailman/listinfo/seesat-l
This archive was generated by hypermail 2b29 : Wed May 19 2010 - 22:06:36 UTC