This mission has been
anything but straightforward.
We have to adapt, we
have to be agile to make
sure that we don't put a $3
billion asset in harm's way.
If you want to effect
what's coming up you need--
These flybys are planned
out many, many months
and sometimes years in advance.
And so if something
is discovered
and we can do something about
it, we'll stop at nothing,
well work literally
day and night in order
to make these new observations
that the scientists you
know desperately
want to make happen.
NARRATOR: Pressure is building
to rethink the route map.
Immediately, the scientists
wanted to get much, much closer
to get high resolution imaging
but also move the closest
approach from the
northern hemisphere
to the southern hemisphere.
We finally arrived at a
solution and we lowered
the altitude from
1,000 kilometers
all the way down
to 165 kilometers.
NARRATOR: This
pass is seven times
closer than the first flyby.
The discoveries are
worth the diversion.
This was the fly
by where we saw,
for the very first
time, these fissures
in the south polar regions.
What was later named
The Tiger Stripes.
NARRATOR: The stripes
are gaping wounds
where pressure from below
opens vents to the surface.
Their marked by
whiter, fresher ice
solidifying along the cracks.
We saw about a
dozen or more jets
erupting 200 or more
kilometers above the surface
of the south pole.
We strongly suspected
that these were geysers.
That this was
vapor and particles
coming from these fractures.
NARRATOR: Nothing now is more
important than Enceladus.
We wanted to go
back again and again
to learn more and even
fly through and taste what
was coming out of those jets.
NARRATOR: The scientists
thirst for knowledge
can but up against the
need for spacecraft safety.
And the guardian of
that is Julie Webster.
JULIE WEBSTER: The engineering
team is the 900 pound gorilla.
If we don't think
it's safe, we win.
But you're there to take science
so if you don't take the data
because you're too
scared you're not going
to get what you're there for.
BRENT BUFFINGTON: We had to
learn a lot about this plume.
What was it made of?
How dense was it?
Was a variable in time?
Variable in geometry?
NARRATOR: To answer
such questions,
Cassini dices with real danger.
BRENT BUFFINGTON: We're
talking about an object
that over a billion
kilometers from Earth.
We went all the way down to 25
kilometers from the surface.
A very, very hard surface.
Going in excess of eight or
10 kilometers per second.
So we're moving.
NARRATOR: The terrifying
maneuver reveals
how active this moon is.
We found over 101
geysers and material
coming from the fractures.
And other teams found
that the vapor contains
simple organic compounds.
Those geysers are coming
from an ocean that is salty.
Comparable to the salinity
of the Earth's ocean
and it's shooting in to space.
