From: (Jim Bell) (by way of Jan Wee <>)
Date: Thu, 04 Dec 1997 06:07:08 -0600

Dear discuss-lfm folks,

Jim Bell posted another note...thought it would be of interest
to all...

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                     Volume 3; Issue 2 
                     December 2, 1997
                     Circulation: 1490

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Friends of Mars,

I have just received the following report of extensive local and
perhaps global dust activity on Mars from members of the Mars Global
Surveyor science team. Along with the MGS data, Todd Clancy reports
corroborating evidence for rapid high altitude warming of the atmosphere
(consistent with increased dust loading) from recent microwave
telescopic observations.

As always, additional optical and infrared observations of this dust
activity would be very useful for tracking the growth and decay of
Mars dust activity, and for assistance with calibration of the MGS science
instruments. Mars is a very challenging observational target
right now (close to the Sun, angular size 4.6 arcsec), but many of you
have risen to the challenge before...  Go catch some dust!

If you are able to obtain images, please upload them to the pub/incoming
directory at the anonymous ftp site (the JPL
Pathfinder ftp site is no longer supported), and send me an email describing
the observations and your interpretations.

------- Forwarded Message

Summary of Mars dust activity observed by the Mars Global Surveyor spacecraft:


Continuing analysis of TES data of the dust storm in Noachis and points west
east).  Results below are based on the entire dataset from drag and all
rolls for 
each orbit.

P049 (Ls=224; 11/25/97):
Small-scale (~300 km) dust activity observed in the Noachis region.

P050 (Ls=225; 11/26/97):
Excellent coverage, with drag pass and first roll giving data centered on the 
Noachis region.  The storm covers latitudes15S-50S, between longitudes 325W-

P051 (Ls=226; 11/29/97):
Scattered coverage of the storm region.  It remains within previous latitudes,
but spreads to 15W, with indications of activity near latitude 25S penetrating
eastward to 305W.  Limited activity north of Argyre (~40S,~50W); some 
increase of dust up the eastern slope of Sinai and Solis Plana (~25S,~65W).

P052 (Ls=227; 11/29/97):
Good coverage east of 345W; sparse coverage to west.  Activity continues to 
spread westward.  Fairly intense activity to 55W at 40S, with limited increases 
as far as 70W.  Storm becoming fairly intense into Hellespontus Montes, and as 
far east as 310W at 55S.  Southern extent to 60S near zero longitude.

P053 - drag and first roll only (Ls=227; 11/30/97):
Consistent with reports by MOC, the storm continues to intensify, spreading 
south onto the polar cap along a broad front from 30W eastward to 290W.  
Considerable activity north of Argyre, and from 10S to 30S at longitude 290W
(we have only drag pass data here so far, and so cannot define the E-W extent of
this activity).  Significant increase of low level dust from there north to 35N.

John Pearl
Mike Smith

------- End of Forwarded Message

Jim Bell
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