Marswatch Newsletter: November 1997

From: (Jim Bell) (by way of Jan Wee <>)
Subject: Marswatch Newsletter: November 1997
Date: Thu, 27 Nov 1997 10:11:35 -0600

Dear discuss-lfm members,

Thought you would enjoy a bit of reading over the Thanksgiving

Enjoy & Happy T-Day!
Jan Wee, moderator of discuss-lfm

O-> O-> O-> O-> O-> O-> O-> O-> O-> O-> O-> O-> O-> O-> O-> O->

                     Volume 3; Issue 1 
                     November 22, 1997
                     Circulation: 1750

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Dear Mars-o-philes,

Resurrected from the ashes, here is the latest installment of what
will hopefully be a much more regular distribution of the Marswatch
electronic newsletter. Primary responsibility for compiling the
latest and greatest information on Mars has now been taken over by
A.L.P.O. Mars recorders Dan Joyce and Dan Troiani. Their first
contribution is provided below. Thanks, Dans!

I will continue to maintain the email distribution list as well
as the various Cornell and JPL Marswatch-related WWW archives. If
you are receiving duplicate copies of this mailing, or you want
your name removed from the distribution list, please send me email.


MarsWatch News: November 1997
Compiled by Dan Joyce ( and 
            Dan Troiani (, 
            Association of Lunar and Planetary Observers

Poor little Pathfinder!  The Sagan Memorial Station has gone 
dormant, not unexpectedly; and NASA plans to continue trying 
about every two weeks to revive it, but hope is fading that its 
batteries will once again prove strong enough to enable significant 
communication with earth.  Despite its success, having sent back 
wondrous images of Ares Vallis both from the mother craft and its 
little sidekick Sojourner for about three times longer than 
anticipated, there is somehow a feeling of regret that this improbably 
popular denizen of cyberspace will just be a memory.

It may be how striking the panoramic vistas were, how mesmerizing 
the 3-D effect was, how cleverly the rocks and features were named 
or even how resourcefully this machine was placed on the surface 
that conjures up the affection we all felt for it.  Maybe it was just 
how small, yet how efficient, this marvel of engineering was, 
especially that diminutive and highly acrobatic rover, that caught our 
collective fancy.  Yet, maybe it was really because the place that it 
landed on was the planet of intrigue, the one that inspires the most 
excitement, and perhaps even to this day a little apprehension, that 
was its charm.  (Probably, for the budget-beleaguered and stressed-
out government, it was the relatively low price tag for the mission!) 

Even a telescope optical technician can appreciate what the mission 
found there; Martian dust was found to be one micron per grain on 
average, perfect for the pre-polish stage!  And dust devils may be a 
leading mechanism for mixing dust into the atmosphere, adding a 
meteorological touch to the overall scheme.  There were surprises to 
be found in the Martian atmosphere and even some unexpected 
results of soil/rock content; sand was apparent.  Verification of the 
suspected watery nature of the Martian remote past was garnered 
very quickly.  The excitement of Pathfinder combined with the 
results of the study of meteorite ALH84001 one year earlier, have 
renewed the concept of life on Mars, including the concept that some 
microbials may yet be found underground somewhere at Mars.  It all 
represents a very great challenge for us to find convincing evidence 
of either their presence or absence.

Congratulations are in order to Project Manager Brian Muirhead, 
Mission Manager Richard Cook, JPL Director Ed Stone, NASA 
Administrator Dan Goldin and the entire Pathfinder team for an 
inspirational effort and the incentive to look forward to future 
missions of this nature.

Speaking of future missions, one is at hand:  The Mars Global 
Surveyor mission, already in orbit around the planet, can be 
considered a great success prior to the official commencement of 
operations!  Despite unexpected difficulties, it has relayed to earth 
images of extraordinary resolution, probably close to twenty-five 
times greater than the Viking orbiters.  One of its solar panels is 
apparently hanging more loosely to the spacecraft than originally 
anticipated, and the Martian atmosphere has greater extent above the 
surface than had been thought, so the planned aerobraking 
maneuvers to circularize the orbit have had to be scaled back enough 
to delay the onset of systematic coverage.  There is apparently too 
much risk of spacecraft destabilization should steep aerobraking 
continue, so only very shallow, time-consuming and closely 
monitored deceleration is being attempted.  This means that the 
planned March initiation of its main task will be delayed about a 
year.  The downside of this is that A.L.P.O.'s carefully prepared 
sequence of anticipated events for Surveyor to watch for, which was 
presented at the Mars Telescopic Observations Workshop in Tucson 
in October, will have to be revised, and in so doing eliminating 
some important, eagerly awaited confirmation of activity which may 
now have to be covered by a subsequent mission.  On the plus side 
is the fact that Mars will be nearing opposition by the time the 
mission is in full gear, so we will be able to conduct meaningful 
contemporaneous observations.  This may at first appear to be 
without merit, or nearly so, given the staggering degree of 
resolution its cameras will have compared to anything earth-based; 
but at least we can spot a transient event which may affect its ability 
to obtain imagery such as clouds or dust.  And what it can see in 
extreme close-up may have profound import for interpretation of 
what we see on the scales we are used to, but only if we are in fact 

Speaking of the Mars Telescopic Observations Workshop II, there is 
nothing like Tucson and vicinity during the dark-of-the-moon 
phases to provide just the right atmosphere for a conference.  Jim 
Bell, Ann Sprague and their colleagues brought together nearly forty 
of us from around the world (Germany, Japan, Belgium and 
England were represented) to present our data and, even at the risk 
of being a bit raucous, speculate about what could be construed 
from it.  There was widespread acceptance of the work of skilled 
amateur astronomers and considerable discussion of the application 
of the observations we have provided.  Particularly graphic was the 
high resolution video of the dust activity of the 1990 apparition 
taken by Don Parker with his 16" f/6 Newtonian which so closely 
resembled the Hubble images of last June, showing dust between 
Chryse and Valles Marineris and suggesting that at least some dust 
might encroach upon the Pathfinder site, which in fact occurred.  
Dan Troiani had, after a thorough review of observations from 
ALPO Mars Section archives centered on the Martian season at the 
time of the landing, passed along his prediction that dust would be a 
factor at the Ares Vallis site at the time of the mission's 
commencement to Jim Bell, our science adviser and mission team 
member, about eight months earlier.  Nice goin', Dan, and we're all 
glad there were no ill effects on the spacecraft.

Concerning dust, though, once again it was emphasized that a red 
filter is most appropriate for visual observations as well as imagery - 
the concept of a "yellow cloud" being associated with dust is being 
heavily downplayed.  "WHAT DOESN'T LOOK BRIGHT IN 
YELLOW LIGHT?" was the oft-heard query.  Still, the jury may yet 
be out as to whether SOME dust on Mars may be more apparent 
with a yellow filter, comparisons between the colors probably ought 
to be made, especially if video is the medium, by as many observers 
as possible during the 1999 apparition, especially given the closer 
proximity to dust season that Mars will be approaching at that time. 
There was considerable discussion that ordinary clouds, those that 
appear conspicuous in shorter wavelengths, that were still bright in 
red light during later stages of the 1996-97 apparition may have had 
a high level of dust saturation.  This had been noted during the 
1992-93 apparition as well, and the correlation, based on the sum of 
other data, including the spectacular dust cloud data set compiled by 
B.A.A. Mars Section leader Richard McKim, now seems more 

Deep down, it seemed that the workshop participants were 
somehow aware that their work is really an important resource for 
scientists planning missions to Mars - and one could not help sense 
that this would include the possibility of manned flights whether we 
are ready for them or not.  In the back of everyone's mind is the 
incentive for such ambition brought about by that ALH84001 
meteorite and even the very popularity of the Pathfinder internet site 
(well over a half a billion hits!).  Obviously, more needs to be done; 
but it now appears that in fact the groundwork has been laid and that 
we can build on that.

Useful WWW sites:

Main MGS Home Page:

Latest MGS images:

Pathfinder Home Page:

A.L.P.O. Mars observations:

1996-97 Marswatch highlights:

1996-97 Marswatch ftp site: