.TH SCAT 7
.CT 1 inst_info
.SH NAME
scat \- sky catalogue
.SH SYNOPSIS
.B scat
.SH DESCRIPTION
.I Scat
looks up items in catalogues of objects
outside the solar system.
Items are read, one per line, from the standard input, and their
descriptions or cross-index listings (suitable for input to
.IR scat )
are printed on the standard output.
An item is in one of the following formats:
.TP
.B ngc1234
Number 1234 in the Revised New General Catalogue of
Nonstellar Objects.
The output identifies the type 
.RB( eg =galaxy,
.BR pn =planetary
nebula, 
.BR gc =globular
cluster, 
.BR oc =open
cluster, 
.BR dn =diffuse
nebula or 
.BR nc =nebular
cluster),
possibly contained within the Large Magellanic Cloud 
.RB ( in\ lmc )
or Small
Magellanic Cloud 
.RB ( in\ smc ),
its position in 2000.0 coordinates
and galactic coordinates, and a brief description.
.TP
.B sao12345
Number 12345 in the Smithsonian Astrophysical Star Catalogue.
Output identifies the visual and photographic magnitudes,
2000.0 coordinates, proper motion, spectral type, multiplicity and variability
class, and HD number.
.TP
.B m4
Catalog number 4 in Messier's catalog.
The output is the NGC number.
.TP 
\f5"alpha umi"\fP
Star names are provided in double quotes.
Known names are the Greek
letter designations, proper names such as Betelgeuse, and bright variable stars.
Constellation names must be the three-letter abbreviations.
The output
is the SAO number.
For non-Greek names, SAO numbers and names are listed for all stars with
names for which the given name is a prefix.
.TP
.B 12h34m -16
Coordinates in the sky are translated to the nearest `patch',
approximately one square degree of sky.
The output is the coordinates identifying the patch,
the constellations touching the patch, and the NGC and SAO
objects in the patch.
.TP
.B c umi
Gives voluminous output consisting of the patches covering the
named constellation.
.SH FILES
.F /n/kwee/usr/rob/sky2/*.sky
.SH SEE ALSO
.IR sky (7)
.br
.B /n/kwee/usr/rob/sky2/constelnames
for the three-letter abbreviations of the constellation names.
.SH BUGS
The database is fine, but the program is feeble.
.br
Coordinates printed by the program in
the listings for SAO and NGC objects are not understood as input.