just like scientific discoveries happen
every day in today's laboratories so
planetary spacecraft over the last
several decades have made startling
discoveries concerning the solar system
we live in
in the quest for better understanding of
the world and universe
galileo the jovian laboratory
the spectacular achievements of voyager
1 and 2 as they flew past jupiter and
its satellites far exceed the
capabilities of earth-based telescopes
new discoveries heighten our awareness
raising new questions
what part do earth and its inhabitants
play in this universal scene
how is earth different from other
planets in our solar system
how are we the same
as voyager past jupiter it discovered a
thin ring about the planet
what is its composition
we know there are 16 moons are there
more
several of the satellites are composed
partially of water ice
one is violently volcanic
how did these bodies form and what is
their history
what can this giant planet tell us about
the history of our solar system
dr torrance johnson project scientist
well jupiter itself of course we believe
to be composed primarily of material
that's very similar and virtually
unchanged uh
in the last four billion years to the
material that formed all of the planets
the fundamental solar nebula if you will
the gas and dust from which all the
planets formed in addition to which the
satellite systems surrounding its
magnetic field
environment make it virtually a
miniature solar system so by studying
this system we can learn a lot about how
the solar system as a whole formed and
something about our own origins
galileo the new generation spacecraft is
designed to spend an extended period of
time in the jovian system
the spacecraft will release a probe to
fly its own trajectory to jupiter
the orbiter is then targeted to its
first encounter io a moon known to have
very active volcanoes
then the orbiter points its relay
antenna toward the probe which begins
its descent into jupiter's atmosphere
once there it will investigate the
composition temperatures and pressures
at varying levels and send data back to
the orbiter
which will re-transmit it to earth
the orbiter will loop through jupiter's
system measuring and observing the giant
magnetic field and plasma as well as the
intense radiation that surrounds jupiter
while performing closer studies of the
moons
the combination of closer encounters and
advanced instrument technologies carried
on board galileo will give much better
definition of surfaces than ever before
specific major advances that we've made
is in the camera system where we're
using the same optical system same
telescope if you will that voyager did
but instead of having a relatively slow
and insensitive vidicon tube
such as was used in tv cameras in the
50s and 60s
instead of that at the focus of the the
telescope we now have a silicon based
device a charged couple device
camera system which gives us a
increase in speed or sensitivity of the
instrument of between 300 and a thousand
times
that allows us to take much higher
resolution pictures much closer
without blurring and it also gives us
access to a little bit of the infrared
part of the spectrum that was totally
inaccessible to the voyager cameras
now in addition to that in the infrared
we have an entirely new device called
the near-infrared mapping spectrometer
which if you will is a little bit like a
landsat type device
giving us images in many different
spectral bands and we'll have about 300
different spectral bands what this means
is we'll have from this device pictures
with relatively modest resolution
spatially but with where each pixel
element within the picture will have a
300 channel spectrum attached we're
going to be using this in both jupiter
and the satellites to map composition on
their surfaces study the characteristics
of jovian clouds find out where ices are
on the surface try to identify the
materials frozen out on the surface of
io for instance
enroute to jupiter galileo will pick up
energy by utilizing gravity assists
while traveling once by venus and twice
by earth
in addition to the bonus of studying
these two planets and earth's moon
galileo will perform close flybys on one
or two asteroids never before closely
observed
then galileo will rendezvous with
jupiter and its moons in 1995.
this unique trajectory will allow
galileo to reach its ultimate goal
returning a bonanza of scientific
knowledge and discoveries from jupiter's
system