Subject: List of Stars in the Autostar From: firstname.lastname@example.org (richard seymour) A few folks have asked about the list of stars (etc.) in the Autostar. Much of what follows is speculation, with some empirical evidence gleaned from using the Autostar to back it up. Whenever you see a commercial product offering "9,000 stars", suspect that they're using the Yale Bright Star Catalog. The Autostar is probably using the 5th edition, and frequently refers to entries in it as HR 5455 or some such. The "HR" is the Harvard Revision of the Bright Star Catalog. (somehow, football-rival Yale's name got dropped...) There is a NASA site (at the Goddard Space Flight Center (GSFC)) which has many, many catalogs, a number of which are combined and edited to create the Autostar's databases. visit ftp://adc.gsfc.nasa.gov/pub/adc/archives/catalogs/ and download the "key" file (as text) It's the index to the hundreds of files at that site. The Yale BSC (above) is entry 5050 Hence it's under the 5/ subfolder, folder 5050 Each of the nine main folders also contains a key, but the top-level key is all of them combined. The files whose names end in ".gz" need to either be fetched in Binary mode, or can be fetched in clear-text by leaving off the ".gz" in your command string. The server will notice that, and uncompress them before sending them. Beware that that will roughly triple their size. Windows people can use a variety of programs to fetch the files. Your Browser can do it, but, like some of the ROM files from Meade, it might mangle the ".gz" form. If you are used to using "ftp", it will do it nicely, just remember to command "binary" transport. I'll add a footnote to this posting with a step-by-step ftp example. Macintosh people seem to universally use "fetch" as their favorite ftp program. The 9,110-star Bright Star Catalog (BSC, or HR) is available at ftp://adc.gsfc.nasa.gov/pub/adc/archives/catalogs/5/5050/ The three files are: (1) readme (which describes the layout of the files) (2) catalog.dat.gz (the bulk of the file) (3) notes.dat.gz (the textual footnotes... many of which the Autostar displays as the scrolling message under many entries). (compare the BSC notes on Polaris (BSC/HR 424) to what scrolls on the Autostar) That file also contains the SAO catalog numbers for the stars. Using that, i've noticed that the Autostar does NOT have the entire BSC (for example, Delta Scutum (BSC/HR 7020, SAO 142515 ) isn't in the Autostar). The Multiple and Variable star menus might be simply derived from keys in the BSC. Which stars are blest to appear in the "Named Star" list versus which stars it knows names for escapes me. The BSC puts "common" names into the notes data. And Polaris has 11 names! The GSFC web/ftp site is divided into 9 major subsets. Category 5: Combined and Derived Data seems to be the most likely source of much of the Autostar data. Other than the obvious BSC, it's anyone's guess (outside of Meade) which other catalogs truly comprise the rest of the bunch. The Nearby Stars might be from 5032A Stars within 25 pc of the Sun (Woolley+ 1970) or 5101 Nearest stars until 10pc (Zakhozhaj, 1979-1996) or simply be ones from the BSC with distances below a certain limit. (pc is parsecs, and a parsec is about 3.26 light years) I suspect the Deep Sky comes from pieces of Category 7: Nonstellar and Extended Objects Entry 7118, for example, appears to be the New General Catalog (NGC). 7118 NGC 2000.0 (Sky Publishing 1988, ed. Sinnott), with 7001B Rev New Gen Cat of Nonstellar Objects (RNGC; Sulentic, Tifft 1973) sounding like a revised version. I don't know... i went bananas when i found this site, and haven't had anywhere near enough time to poke through all the files... (and me with a 28k modem!) Some specialized pieces of the Autostar database have probably been hand-prepared by Meade: things like the "Stars with Planets" list. The GSFC database doesn't contain a specific Messier catalog. (Since Messier objects span the gamut from star groupings (Pleiades) through Nebulae, they likewise would be scattered across many of the GSFC files). Some of the scrolling comments involving "small telescopes" are possibly Meade's, too. Meade also has the data behind the LX200's controller, and their Epoch 2000 software to draw upon. And where they get "3C273" as being a DeepSky>NamedObject is beyond me. (they're welcome to include it... it's a 12.8 magnitude Quasar, but the scrolling text doesn't mention that it's the brightest one in the sky) Let's look at the LX-90's advertised database: 30,233 objects. 13,235 Deep Sky: the complete Messier, Caldwell, IC and NGC. 16,888 Stars sorted by name and SAO numbers Well, i think that the SAO is about 240,000 stars, so there's been a bit of trimming. (i think the SAO is entry 5015 at the GSFC site). The IC (Index Catalog) is (are?) two supplements to the NGC. The original NGC was compiled in 1888, and the IC supplements were in 1895 and 1908. Think about it... we didn't know about Galaxies being what they are until well after 1900... until photographic emulsions became good enough to capture the faint light allowing us to finally see the structure of "island universes" like the Andromeda Galaxy. And then it dawned that they weren't just fuzzy stuff in a randomly distributed sea of stars, but were reflections of what our local star cloud (the Milky Way) must look like. But that's a digression for another day... --dick How to use FTP to fetch a GSFC database from Windows 95/98/2000: NOTE: The other end is "case sensitive"... that means you have to carefully follow/mimic the UPPERCASE and lowercase letters in filenames and commands! (like: readme is really ReadMe ) Create a folder (preferably in the root directory of your C: drive) I'll call it "goodies" for the example below. Go online in your usual fashion. Then click on the Windows [start] button. Then click on "Run..." In the dialog box, enter: ftp adc.gsfc.nasa.gov A black MS/DOS window should appear, and you'll see FTP connecting to Goddard. It'll ask for a Username: Tell it: anonymous It'll ask for a password: Give it your real Email address ( so i'd say: email@example.com) You should now be logged on, and facing an ftp> prompt. Tell it: bin (that commands ftp to operate in binary mode) Tell it: lcd c:\goodies (that commands ftp to do a Local Change Directory to your new folder) Tell it: cd /pub/adc/archives/catalogs (that means "change directory" at the other (GSFC) end) (and yes.. the slashes go as shown (/), not (\)) Tell it: dir You'll see a number of directories listed, and (at least) one file: key Tell it: get key key.txt (that tells ftp to "get" the file called key, and to rename it to key.txt here on your PC) You'll see the transfer reported (sorry, no flying pages) *at this point, you might log off and poke thru "key" for interesting items... but i'll assume you want the BSC...* Tell ftp: cd 5 Tell ftp: cd 5050 tell ftp: dir tell ftp: mget * (multiple get, all files) It'll ask you about each file. Answer y or n as appropriate. If you want the GFSC server to uncompress the files for you, then you have to individually get the files, without the .gz suffix. This is a special feature of their server, it won't necessarily work elsewhere. WinZip can unpack a .gz file. To move back up the directory tree, you can tell ftp: cd .. which will move you up one level. To log off from their server, tell ftp: quit Please don't just hang around on it, you're occupying a limited number of login slots. The MSDOS window will disappear after the logout. For just poking around the GSFC directories, but not recommended for fetching files, you can use your Web Browser. Start with the URL: ftp://adc.gsfc.nasa.gov/pub/adc/archives/catalogs/ If you don't have WinZip (you should... get it from www.winzip.com), you can command GSFC to unpack the files before sending them. Look at my ftp instructions, and follow them down to the line: mget * Don't do that line (unless you've got WinZip... then do it, and simply let WinZip open the resulting mumble.gz file as an archive) Instead, do the following three lines: get catalog.dat get notes.dat get ReadMe That should bring the files over in a way that Wordpad can handle them. (it's what i use) The ReadMe describes which columns in the catalog.dat file mean what. After you've done the above three lines, resume following the instructions after the "mget *" command. have fun --dick P.S. aaaannnnddd of course i forgot to insert SAO (Smithsonian Astrophysical Observatory) anywhere in there.
Return to the top of this page.
Go back to the Autostar Information page.
Go back to the ETX Home Page.