--- David Nicholls <[EMAIL PROTECTED]> wrote: > > So that means CDC will only accept the first 99999 asteroids in > astorb.dat, because all higer numbers use 6 digits?
No, the problem only affects the numbered asteroids. Asteroids only get numbered (and named, if the discoverer is interested in naming it) after they've been observed long enough that the orbit is well enough known that there's little chance it will get "lost". That typically takes a few opposition cycles, or typically around 5 years. Before that, the asteroid is known by a "provisional designation" that looks something like "2003 TK47". There are over 300,000 known asteroids, but the number with permanent numbers only just passed 100,000. > In practice one would probably only ever want to identify the named > asteroids, and these number around 25000. 12779, as of December 15. See <http://cfa-www.harvard.edu/iau/lists/ArchiveStatistics.html> But I disagree with your premise. I'm one of many amateurs making follow-up astrometric (position) measurements of newly discovered near-earth asteroids, to help refine the orbits of these objects. I use CdC to help locate the objects and point the scope, for CCD imaging. And then there are events like the close pass of 2000 NY40 in November 2000, which was so close you could watch the asteroid move in real time in the EP. > This reduces the dat file to > around 6MB, compared to the full file at 80+MB. If you're looking for one or a few objects that aren't in the short "bright or unusual" list, and you don't want to deal with the full astorb file, you can get a customized file of asteroid elements from <http://cfa-www.harvard.edu/iau/MPEph/MPEph.html>. Enter the objects you want, skip the middle portion, then under "format", select "TheSky" (same format that CdC uses). It will download a file called "elements.txt", which you can either cut/paste to append into your current asteroides.dat file, or just rename it to replace your old file (in the ciel/cat/planet folder). You can do the same with comets, and the "cometes.dat" file. -John __________________________________________ Yahoo! DSL Something to write home about. Just $16.99/mo. or less. dsl.yahoo.com ------------------------ Yahoo! Groups Sponsor --------------------~--> Get fast access to your favorite Yahoo! Groups. Make Yahoo! your home page http://us.click.yahoo.com/dpRU5A/wUILAA/yQLSAA/1.XolB/TM --------------------------------------------------------------------~-> Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/skychart-discussion/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
