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            --.    THE INTERNATIONAL MARSWATCH ELECTRONIC NEWSLETTER
     .  ..../ |    -------------------------------------------------
       ::::::      Volume 2; Issue 2 (file imw.oct96)
       ::::::      October 1996
        ::::       Circulation: 199

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CONTENTS-------------------------------------------------------------------
-                                                                         -
-  Hubble Space Telescope Observes Martian Polar Dust Storm               -
-  Next HST images scheduled; Groundbased supporting images sought        -
-  Reminder about Marswatch-related WWW pages and addresses               -
-                                                                         -
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HST Catches a Dust Storm in Action!
-----------------------------------
The first images of Mars obtained by the Hubble Space Telescope since the
planet emerged from solar conjunction earlier this year have revealed
evidence for an atmospheric dust storm in the north polar regions. The
images, obtained by Phil James (University of Toledo) and colleagues from the 
University of Colorado, Lowell Observatory, the Space Science Institute, and 
Cornell University, were obtained on September 18 through 9 color filters from 
the UV to near-IR and are centered on the Elysium region (CM=165). The dust 
storm covers a region from approximately 160-200 degrees W longitude and 
55-70 degrees N latitude, and is visible as a distinctly reddish cloud 
overlying the dark surface regions and polar cap units normally visible in 
these areas at this particular season (Ls=11).  The HST Mars team is 
continuing the analysis of these images, and a public-release photo will be 
produced soon and posted on the WWW.  In the meantime, observers who may have 
corroborating groundbased data from this time period or shortly before/after 
are encouraged to communicate their results to the Marswatch project, so that 
a more complete understanding of the evolution of Mars dust storms and the
nature of Mars dust activity prior to the upcoming Mars missions can be 
obtained.

The orientations of Mars and the Earth are allowing excellent views of the 
Martian north polar region during this apparition, and it is hoped that 
additional events like this one will be detectable by HST as well as
groundbased observers.  For more general information on the goals of the 
HST Mars imaging campaign, see the URL:

                 
                 http://mpfwww.jpl.nasa.gov/mpf/hst.html


Next series of HST Mars Images Scheduled
----------------------------------------
HST will next observe Mars on October 8, 9, and 15.  The images will be
obtained using 9 filters from the UV to the near-IR and are designed
to provide global imaging over a period of three HST visits. These images 
will provide the first HST views of the Pathfinder landing site since July
1995.  Because of scheduling constraints, this global HST view of Mars will 
take nearly a week to assemble, and so groundbased observations of Mars
during this time period may help to determine how the Martian surface
and atmosphere are changing during this one-week period. If you are able
to observe Mars during this time period, please submit your observations
to the Marswatch ftp archive. You can find out how to do this at URL:

       
       http://mpfwww.jpl.nasa.gov/mpf/marswatch_ftp.html

The specific times of the HST observations are:

     Date       Time Range (UT)       Central Meridian Longitude
  -----------   ---------------       --------------------------
  October 8     16:10 - 17:02           285
  October 9     00:13 - 01:08            45
  October 15    13:54 - 14:41           165


MarsWatch Web Sites
-------------------
Just a reminder about some of the URLs that you can link to in order to
find more information and background on the Marswatch project:

Main 1996-97 Marswatch Web site:

     
     http://mpfwww.jpl.nasa.gov/mpf/marswatch.html

Goals and Outline of the 1996-97 Marswatch Project:

     
     http://astrosun.tn.cornell.edu/marsnet/imw/marswatch96.info
 
HST Observations and Marswatch:

     
     http://mpfwww.jpl.nasa.gov/mpf/hst.html

1994-95 HST Mars image archive:

     
     http://marswatch.tn.cornell.edu/hst_archive.html

1994-95 Marswatch Web site:

     
     http://astrosun.tn.cornell.edu/marsnet/mnhome.html

-----------------------------------------------------------------

Jim Bell and Bob Anderson

Editors, IMW Newsletter
-----------------------------------------------------------------
Cornell University
Department of Astronomy
Center for Radiophysics and Space Research
424 Space Sciences Building
Ithaca, NY 14853-6801
phone: 607-255-5911
fax: 607-255-9002
email: jimbo@cuspif.tn.cornell.edu
WWW: http://marswatch.tn.cornell.edu
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