of 1
JOURNAL
OF
GEOPHYSICAL
RESEARCH,
VOL.
97,
NO.
E5,
PAGE
7663,
MAY
25,
1992
Foreword
The
Mariner
and
Viking
missions
have
explored
Mars
and
have
removed
much
of
the
mystery
that
has
intrigued
mankind
for
cen•es.
This
knowledge
allows
scientists
to
pose
complex
questions
about
the
origin,
surface
history,
magnetic
field
and
interior,
atmosphere,
and
climate
of
Mars.
We
know
enough
to
pose
such
questions,
typically
based
on
a single
data
set,
but
we
do
not
have
additional
data
sets
with
which
to
test
these
questions.
Mars
Observer
was
conceived
as
a mission
whose
observations
would
constitute
a synergistic
army
of
data
sets
that
would
be
readily
available
to
the
global
community
of
planetary
scientists.
It provides
a low,
Sun-synchronous,
polar
orbit
about
the
planet
from
which
the
entire
surface
and
atmosphere
can
be
repetitively
observed
and
mapped
by
remote
sensing
instruments
for
an
entire
Mars
year.
This
long
period
of
continuous
observations
promises
a rich
harvest
of
global
and
•e. asonal
information.
It will
provide
a basic
understanding
of
Mars
as
it exists
today
and
a framework
for
understanding
its
past.
Mars
Observer
stands
between
the
initial
exploration
of
Mars
and
the
more
intensive
explorations,
possibly
involving
human
beings,
that
are
only
now
being
planned.
Arden
Albee
Chief
S•ientist,
Mars
Observer
Project
Guest
Editor
Copyright
1992
by
the
American
Geophysical
Union.
Paper
number
92IF•724.
0148-0227/92/92.W,-00724502.00
7663