Question about a fits header

[Bill Wyatt]

Since there are 86,400 seconds in a day, and there was a DATE keyword,
52917 is surely is the second of the indicated day.

Thomas A. McGlynn (tam at silk.gsfc.nasa.gov) wrote:
: >Patrick Wallace wrote:
: >> 
: >> On Wed, 4 Sep 1996, Alanna Spehr wrote:
: >> 
: >> > I have fits files that have:
: >> >
: >> > OBS_TIME=                52917
: >> >
: >> > in their header. (Along with OBS_DATE and DATE, if it matters.)
: >> > Can somebody tell me what the 52917 is, and how I can change it
: >> > to something more useful?
: >> 
: >> My guess is it's a Modified Julian Date (JD-2400000.5).  A procedure
: >> for turning an MJD into year, month, day is appended.  There are
: >> other ways of doing it (see the Explanatory Supplement to the
: >> Astronomical Almanac).
: >> 
: >> Patrick Wallace
: >> 
: >Alas, MJD 52917 is about 7 years in the future.  I think
: >you need to get in touch with whoever wrote the FITS file
: >to find out what it means.
: >		Tom McGlynn


--
Bill Wyatt  (wyatt at cfa.harvard.edu)
   Smithsonian Astrophysical Observatory  (Cambridge, MA, USA)