Status Report #148: ROSAT NEWS No. 51

[Michael Arida <arida@urania.gsfc.nasa.gov>]

Date: Fri, 31 Jan 1997 11:14:41 -0500 (EST)
Subj:	ROSAT NEWS No. 51


=========================================================================
=                                                                       =
=              ROSAT NEWS No. 51     ---     1-Feb-1997                 =
=                                                                       =
=-----------------------------------------------------------------------=
=                 ROSAT Scientific Data Center at the                   =
=       Max-Planck-Institut fuer Extraterrestrische Physik (MPE)        =
=               Postfach 1603, D-85740 Garching, Germany                =
=-----------------------------------------------------------------------=
=  e-mail address:   rosat_svc@mpe-garching.mpg.de                      =
=  ROSAT Service Area (including ROSAT Data Archive):                   =
=   www address:  http://rosat_svc.mpe-garching.mpg.de/                 =
=   ftp rosat_svc.mpe-garching.mpg.de      user: anonymous              =
=   interactive account (including ROSAT Result Archive):               =
=     telnet xray.mpe-garching.mpg.de  user: xray  no password          =
=-----------------------------------------------------------------------=
=  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)     =
=   www address:  http://astro.uni-tuebingen.de/rosat.html              =
=========================================================================


Contents: ROSAT STATUS
          ROSAT ALL-SKY SURVEY REPAIR
          NEW TIMELINE 


ROSAT STATUS
============
On December 19, 1996 the satellite entered the safemode caused by an
erraneous signal of the star tracker. Normal timeline operation was
resumed about 11 hours later.

On January 17, 1997 a routine reset of the spacecraft clock was
initiated.


NEW TIMELINE 
============
A timeline and a timeline summary  for HRI observations during 
the period January 20 to March 2, 1997 is available in the ROSAT
Service Area:
http://ftp.rosat.mpe-garching.mpg.de/rosat_svc/timeline/
files ao7_hri2.timeline and ao7_hri2.summary.

The timeline for the time after March 2 is in preparation.


ROSAT ALL-SKY SURVEY REPAIR
===========================
On February 3 the ROSAT PSPC will be turned into the focal plane and 
the high voltage switched on.  The goal of these operations is to fill 
up the gaps remaining from the all-sky survey observations taken in 
1990 and 1991.  This survey repair consists of a sequence of about 500 
short duration PSPC pointings.  Since it is unclear how much PSPC gas 
is actually left the observations were categorized into three groups, 
mandatory, important and optional ones.  The mandatory observations 
will be carried out first and are designed in such a way that no point 
in the sky remains with an exposure below 30 sec; they will be 
finished after twelve days. The second group of "important observations" 
will ensure a minimum offset angle of no more than 30 arcmin for all 
points in the sky with less than 75 sec exposure and will be finished 
after 25 days. The optional fields cover those areas that received less 
than 150 sec of exposure and cannot be fully completed in the available 
time frame.  HRI observations will be resumed on March 2, even if there 
should be any PSPC gas left.  If the PSPC gas runs out prematurely, 
an HRI backup timeline consisting of low priority HRI observations will 
be carried out.

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


___________________________________________________________________________
Michael Arida, (HSTX) ROSAT/ASCA GOF                LHEA/HEASARC
ph: 301-286-2291 (voice)                       Code 664, NASA-Goddard
arida@rosserv.gsfc.nasa.gov                      Greenbelt, MD 20771