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From: sterner@warper.jhuapl.edu (Ray Sterner)
Subject: [astro] Re: Anyone know where the yale star catalogue may be FTP'd from ?
Message-ID: <1991Mar16.200938.9621@ox.com>
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References: <9103131403.AA05216@ucbvax.Berkeley.EDU> <1991Mar14.151628.288@ulrik.uio.no> <93191@lll-winken.LLNL.GOV> <sterner.669049584@warper.jhuapl.edu>
Date: Sat, 16 Mar 1991 20:09:38 GMT
Approved: emv@msen.com (Edward Vielmetti, MSEN)
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Archive-name: astro/catalog/yale-bright-star/1991-03-15
Archive-directory: mandarin.mit.edu:/astro/data.etc/yale.bright/ [18.82.0.21]
Original-posting-by: sterner@warper.jhuapl.edu (Ray Sterner)
Original-subject: Re: Anyone know where the yale star catalogue may be FTP'd from ?
Reposted-by: emv@msen.com (Edward Vielmetti, MSEN)

loren@tristan.llnl.gov (Loren Petrich) writes:
>       On the subject of the Yale Bright Star Catalog, does anyone
>       know how complete it is advertised as?
>       The measure I would be interested in is a magnitude upper limit.
>       Is it complete to only magnitude 5.0, or 6.0, or 7.0?
>       And if there are several editions of it, what is the most
>       complete one, and where may it be found?
>Loren Petrich, the Master Blaster: loren@sunlight.llnl.gov

   Here is a histogram of the visual magnitudes in the YBS (4th ed):
     
     Magnitude       Number
       Range        of stars
   -2.00  -1.50        0
   -1.50  -1.00        1      Brightest star = -1.46 = Sirius
   -1.00  -0.50        1
   -0.50   0.00        3     
    0.00   0.50        5       
    0.50   1.00        5
    1.00   1.50        7
    1.50   2.00       29
    2.00   2.50       43
    2.50   3.00       87
    3.00   3.50      116
    3.50   4.00      243
    4.00   4.50      397
    4.50   5.00      754
    5.00   5.50     1299
    5.50   6.00     2254
    6.00   6.50     3286
    6.50   7.00      524
    7.00   7.50       36
    7.50   8.00        6      Faintest star = 7.96
    8.00   8.50        0

    The YBS is obviously not complete to its faintest magnitude.
    It is certainly complete to some limit (0 -1.4 for instance)
    but that limit may not be very faint, I don't know what it is.
    It also contains 14 non-stellar objects which have their
    magnitudes set to exactly 0.0, none of the stars in the catalog
    have a magnitude of exactly 0, so this is an easy way to find the
    non-stellar objects (they have been removed from the above histogram).

    The YBS is a catalog of 9110 objects (9096 stars).  It will never be
    complete to its faintest magnitude, but it includes many other
    values that are updated occasionally.

  Ray Sterner                     sterner%str.decnet@warper.jhuapl.edu 
  Johns Hopkins University        North latitude 39.16 degrees.
  Applied Physics Laboratory      West longitude 76.90 degrees.
  Laurel, MD 20723-6099