Rosat status report 79

[REQUEST@rosat.gsfc.nasa.gov]

		ROSAT Status Report # 79
		      Dec 23rd 1993

	   Redistribution of MPE Status Report


=========================================================================
=                                                                       =
=              ROSAT NEWS No. 24   ---     23-Dec-1993                  =
=                                                                       =
=-----------------------------------------------------------------------=
=                 ROSAT Scientific Data Center at the                   =
=       Max-Planck Institut fuer Extraterrestrische Physik (MPE)        =
=                 Postfach 1603, 85740 Garching, FRG                    =
=-----------------------------------------------------------------------=
=  e-mail addresses (Uli Zimmermann):                                   =
=   rosat_svc@mpe-garching.mpg.de (Internet) or                         =
=   MPE::ROSAT_SVC (SPAN)                                               =
=  ROSAT Service Area read-access via anonymous ftp:                    =
=   ftp rosat_svc.mpe-garching.mpg.de (130.183.72.180) user: anonymous  =
=-----------------------------------------------------------------------=
=  XUV Center: 29382::GXUVDC or  GXUVDC@AIT.PHYSIK.UNI-TUEBINGEN.DE     =
=   WFC Archive access via telnet/ftp ait.physik.uni-tuebingen.de       =
=                                user: xuv  (password: xuv_archive)     =
=========================================================================



            .      The ROSAT team at MPE wishes you           .           
    .                                                                     
                  .        .               .                   .         .
   .   .                                  .         .                     
     MERRY CHRISTMAS           |                                    .    
                .            \   /                               .       
   .   .                    _  ^  _                 .       .            
.                           . (.) .                                     .
         and  a        .     |___|        .                              
                        .    |\  |         .         .         .         .    
     .                       |/  |                           *         . 
             .               |\  |       .         .      ***            
                             |/  |            .        #####             
   .   successful     .      |\  |                #######              . *  
              .              |/  |   .       #####***######        .     
         .   .               |\  |           *****######               **
    NEW  YEAR  1994          |/  |   ***** *****######        ##***######
                       .     |\  |      ##***#########*** ##***#########*
                             |/  |   .  .       #####***#########***     
   .          . *******    . |\  |         ##***#########***             . 
                    ## #** ##|/  |**###*##**#   ##***#########***        
     ##***#########*** ###*##**#*#*###*#########         ##***#########**
##***#########***#**#   ###*##**####*##**#   ********               *****


ROSAT is now three and a half year in orbit and the quality of the X-ray
images has not degraded since the 'first light' pointing on the LMC.
In addition to the enormous database produced in the All-sky Survey, ROSAT 
took data from 3897 pointings (up to December 3, 1993) on individual 
objects. From a total of 34 012 672 sec time on target 14 % were 
taken with the HRI and 86 % with the PSPC in focus. Data processed and 
archived at the Data Center at MPE amount to about 500 GBytes.


SATELLITE STATUS
================
On November 17 ROSAT went into safemode because of a permanent Z-gyro
failure.  On November 26 timeline operations were resumed with a 
modified observing program, constructed under the boundary conditions 
that slews occur only on the day side and no observations be carried 
out with a sun cone angle between 85 and 95 degrees.   This program 
worked successfully until December 18 when ROSAT entered safemode
again. During the following days different attempts to recover from 
the safemode were only partially successful and never for more than 
one orbit. On December 22, the wobble was disabled. Since then ROSAT
appears to function orderly. If the situation continues to be stable 
it is planned to switch to the nominal HRI timeline on December 24. 
The reasons for the frequent safemode occurrences and whether they 
are really linked to the operation of the wobble mode are presently 
not understood and under intense study by GSOC.
First checks indicate that the HRI, which was not operated for about 
half a year, behaves nominally.

MISSION PLANNING
================
The list master_obs.list in the ROSAT Service Area has been updated
and contains now all ROSAT observations performed and processed at 
MPE until December 3, 1993.
In addition the present HRI timeline and a summary timeline can be
found there. 


EXSAS/MIDAS
===========
The new MIDAS 93NOV release has been received at MPE on December 13. In
the meantime we have tested the updated EXSAS 94JAN version in this 
environment for the UNIX based systems DEC ULTRIX, SUN and HP. We will
immediately ship this version of EXSAS to the institutes that have
already replied to our EXSAS Questionnaire sent last week to all the
institutes presently on our distribution list. The DEC VMS version is 
expected to be ready for distribution at the begin of January.

The OSF version of MIDAS (for the DEC ALPHA processors) looks good and
can hopefully also be released on the January timescale. 

====================== end of ROSAT NEWS ================================