We got a booming carrier... Everything looks great.
A billion miles from home...
Ansco systems, Cassini Ace...
Running low on fuel... We have a good lock.
Almost out of time.
We're putting down a fully functioning spacecraft.
After 13 years orbiting Saturn,
the spacecraft Cassini
is about to plunge to a fiery death,
becoming part of the very planet it has been exploring.
Cassini was not so much of a mission as a way of life.
I've spent 20 years of my life on this.
What we found was spectacular.
Cassini sent back dramatic visions of strange new worlds.
Nothing of what we had imagined came close to the reality.
It revealed methane lakes, electric dunes, varied oceans.
That moon has an ocean in it that could harbor life.
It's the end of a mission that has not only unveiled the beauty
and probed the mysteries of Saturn,
but has changed our view of the solar system forever.
Captions by vitac... www.vitac.com
captions paid for by discovery communications
Systems lead, mission planning.
Go ahead, mission planning.
The spacecraft has just crossed 30 degrees north latitude.
Altitude is 6,000 miles.
The dead of night, Friday the 15th of September
in the control room
of NASA's jet propulsion laboratory...
The flight director and her team of engineers
are presiding over the death of a spacecraft
that they have nurtured for nearly three decades.
Ansco systems, Cassini's station...
In less than an hour, they will watch as Cassini
sends its final transmission.
- Copy. - It's sad.
It was 27 years of the investment
of many lives into this.
Nearby, at the California institute of technology,
is the vast family of scientists from around the world
who run the 12 instruments on Cassini,
measuring everything from infrared to radar,
magnetic fields, and cosmic dust.
In some ways, I just want it to be over now...
You know, you're sort of waiting for it to end, and...
And it's really weird.
Very mixed emotions at the moment... really strange.
All have played a vital role in exploring Saturn.
But it's Cassini's skills with a camera
that have been truly inspirational.
Head of the camera team
and guardian of the Cassini image gallery
is Carolyn Porco.
Carolyn has been responsible for designing the camera systems,
deciding when, where, and which pictures to take,
and delivering and processing
hundreds of thousands of images of Saturn...
Its rings and moons.
This is one of my favorites.
The reason why I love it
is because we're seeing the rings edge on,
and you just really can tell how thin they are.
You can get the sense of three dimensionality.
And this is the famous hexagon, okay?
This is the feature that drives everybody crazy
because they don't expect to see something
that is straight-sided in an atmosphere.
It is nothing more than a jet stream like our jet stream.
Okay, really. You can relax.
This is not the end of the world.
Back at the rings... I mean, have you ever,
ever seen anything
just so magnificently regular and beautiful?
With its two on-board cameras,
Cassini has unveiled the Saturn system
as a strange, mysterious, and unique place.
Saturn just captivates people
because it looks so supernatural.
It engenders the immediate feeling
that it can't possibly be real.
But we're lucky to have it.
I think we're damn lucky to have Saturn.
I glad I grew up in a solar system
that had a planet like Saturn.
But taking and downloading such amazing pictures on your camera
that's a billion miles away through the bleak void
of outer space is no easy feat.
In charge of remotely managing this spacecraft
from NASA's jet propulsion laboratory is Julie Webster.
You know, scientists and engineers are true nerds.
So you'll see a lot of nerds stuff on the
Julie is Cassini's chief engineer.
She's been caring for the intrepid explorer
since before it left home,
and uses a scale model of the spacecraft
to demonstrate its capabilities.
This is a quarter-size model, so this is a quarter-size me.
I'd like to be this weight, not this height.
So you start at the top.
This is a four-meter antenna.
It was also designed for radar.
So this is the composite infrared spectrophotometer.
This is the ultraviolet spectrophotometer.
This is the VIMs, visual and infrared.
And these are the imaging cameras,
the narrow angle and wide angle
that are used for the actual photos that you see.
So this is the ion and neutral mass spectrometer
that is the most important data
that we're gonna get in the last few hours.
And here's part of the magnetometer instrument,
and here's the other half of the magnetometer instrument.
The... trick is... The reason you want
to put it out on a boom, is you do not want to measure
the magnetic field of the spacecraft.
You want to measure the magnetic field of Saturn
or whatever you're at the time.
Let's see... That's the nuclear battery.
I actually sat inside this part during the build,
so when I close my eyes and think of Cassini,
I actually see the wiring inside the spacecraft,
and the things switching on and off,
and when it goes in that's...
That's what I'm going to see in my mind, is the...
Is the aluminum melting on the structure.
So now we're headed back up to the first floor to my office.
Cassini divides its time between gathering data,
which it stores on its internal memory,
and then sending it back home.
A typical day we're out taking pictures, collecting data,
storing it on the solid state recorder,
and then we'll turn back to earth,
and we'll play it back for nine hours.
We only have four gigabits of data that we can load up,
and it takes nine-plus hours to play that data back.
For nine hours at a time up to six times a week,
Cassini sends its precious images of Saturn
on the billion-mile journey back to earth.
We have cleared the tower,
and the Cassini spacecraft is on its way to Saturn.
So what does it take to get a spacecraft the size of a bus
with 12 delicate instruments all the way to Saturn
and to keep it operating for 20 years?
And the solid rocket boosters have been...
In the mission to get closer to Saturn than ever before,
getting the Cassini spacecraft to its new home
was a challenge for the team of fearless rocket scientists.
So, we'll go into the dark room.
Inside the dark room, the mission-support area
is where the whole flight team gathers for critical events,
like the final plunge, launch, or orbit insertion.
It took seven years to get to Saturn,
a spiraling journey that involved four gravity assists,
close flybys past planets
that boost the speed like a slingshot.
It's a flight plan designed by head of navigation, Duane Roth.
- We had a Titan iv-b launch? - Titan iv-b.
So that... that was to get us away from the... the earth,
but then it still wasn't quite enough
to make it all the way to Saturn,
so we had two Venus flybys,
gravity assists from each of those, an earth gravity assist,
and finally we've got a Jupiter gravity assist,
and that got us to Saturn.
Once Cassini was approaching Saturn, it had to perform
possibly it's most critical maneuver of the mission...
A perfectly timed engine burn that would slow it down enough
to be captured in orbit by the giant planet.
Saturn orbit insertion was, obviously,
incredibly nerve-wracking.
We spent seven years guiding this spacecraft
to get to Saturn, to get it into orbit.
If it hadn't done the orbit insertion,
which was a 90-minute burn on the main engine...
If we hadn't done that, we'd have been a Saturn flyby
and just gone on out in space.
The Doppler has flattened up.
During its 13-year stay, Cassini has revealed Saturn
as a unique Jewel in the solar system...
A gas giant with swirling storms,
a dancing sprinkling of moons,
and surrounded by bright but paper-thin rings of ice.
The origin of the rings is still a mystery,
as is the complex gravitational interplay
between rings, moons, and planet.
So, this is one of those discoveries we made
that really threw us for a loop.
This is the outer edge of the "B" ring,
and these, as you can see,
are spiky shadows that are created by these features here
that are sticking out two-and-a-half miles,
two-and-a-half miles above a sheet of debris
that's only 30-feet thick.
It was just extraordinary.
It was out of science fiction.
That's what this whole mission has been.
But hidden in the images from Cassini
are clues to the formation of this complex and dynamic system.
Well, we know the rings of Saturn are...
Are made of ice,
and this is a really solid block of ice here.
But this is not the sort of ice the rings are made of.
Carl Murray is part of the imaging team
trying to work out how rings make moons and moons make rings.
These sort of things... it's moire like sort of fluffy ice,
so it's really the difference between
a snowball and a hail stone.
So this would be like a hail stone,
but if you kind of break it up,
you start to get more of a flavor for what the...
The ring particles might actually be made of.
And the fluffy nature of the ice kick-starts
the process of clumping.
So, if the ice is fluffy, the particles, perhaps,
are more likely to coalesce,
rather than to break up or bounce off each other,
because there's more surface area for the particles to stick.
Eventually, gravity can take over, and a moon can be born,
and it's the moons of Saturn, rather than the planet itself,
that have offered up many of the most incredible surprises
and mysteries to be solved.
They're incredibly diverse,
ranging in size from a few hundred feet
to bigger than the planet Mercury.
But out of all these moons, the two standouts are Titan
and then Enceladus.
Before Cassini's intrepid voyage,
our best view of Titan was as an orange, foggy blob.
Titan was so mysterious to us before we got there.
At first sight, it may not look like much,
but peer through the fog,
and an astonishing world is revealed,
a world that surprised everyone.
We hadn't let our imaginations go as wild
as nature turned out to be.
On December 24, 2004, Saturn’s mysterious moon Titan
began revealing its secrets to an eager audience
when Cassini dropped a passenger...
The European-built Huygens probe.
The Huygens' deploy... We actually did that
on Christmas Eve in here.
It was the last year my father was alive,
and this was a really important thing for him,
and so he was sitting...
He was able to sit up in the balcony
and see his daughter say, you know, "release the probe."
Huygens was designed as a descent module...
Go through the atmosphere
and tell us everything we can find out about this...
This sister to our own atmosphere.
Planetologist Athena Coustenis has been with the mission
since the beginning.
And as Huygens fell through the orange atmosphere,
she was at the European space agency's mission control
in Germany, waiting anxiously for news from Huygens
to find out if it survived the descent.
I remember telling my colleagues,
"please remove this image of Mars...
This photograph of Mars here.
We're waiting for Titan."
And they said, "but it's Titan." And I said, "no."
It's Titan. We can see the pebbles on the ground.
We can... We can see the surface.
And we're there, and the probe is taking images
continuously of the same spot.
The parachute goes right above,
and so we can see the shadow of the parachute.
That was the first image they saw,
but the best was yet to come.
Huygens was busy gathering valuable data
during the 2 1/2-hour descent through the orange gloom.
These are actual images taken during the descent,
joined into a seamless film,
together with the recording made by Huygens
of the sound of Titan's orange atmosphere.
And we started seeing channels carved through the hills,
and we had this very dark area in the middle that, eventually,
we identified as a dry lake.
Nothing of what we had imagined came close to the reality.
Long after Huygens was tasting the atmosphere
and snapping pictures at the surface,
Cassini continued to explore Titan far above.
We went by Titan over 125 times.
Each flyby needs to be incredibly precise.
And to prepare for them, Julie has a simulation of Cassini
and the universe around it... Hello.
The integrated test laboratory.
- A real-time? Absolute time? - We want it to be absolute.
She uses the mock-up to anticipate every eventuality
and rehearse every maneuver.
We must have run 10,000 simulations.
When you fly spacecraft, you have to learn how to fly them,
so the first two or three years were the most difficult,
'cause you're kind of learning how...
What makes the personality of the spacecraft.
Cassini was originally intended to orbit Saturn
for just four years.
These are years by color.
But the mission has been so successful,
it's been extended twice.
By the end of the mission,
it will have done a total of 293 orbits,
covering every corner of the system.
Right?
Careful planning and endless simulations by Julie
and her team kept Cassini in full working order,
even after 20 years in space.
There's engineers, and there's science,
and we're the engineers.
So, scientists like to constantly be surprised, right?
They like new data.
They like to say, "oh, I don't know what this means.
I don't know what that... that can't... there's something new."
Engineers do not like to be surprised.
And Cassini didn't disappoint the scientists.
It delivered plenty of mystery and surprise.
These are dune fields, and they're...
The dunes are enormous.
They're several kilometers apart, they're 100 meters high,
and they go on and on for hundreds of kilometers.
In all these dark areas that you see, it's covered with dunes.
At first look, these dunes look remarkably
like the very largest dunes found on earth.
But a more careful investigation reveals
some very crucial differences.
The sand on Titan's dunes
doesn't blow in the prevailing wind,
and the dunes seem to be resilient to all
but the very strongest of storms.
Joshua Méndez Harper and George McDonald
have been trying to work out
what's so special about Titan's sand.
One idea is that these dunes are cohesive, or sticky,
that the grains that make up these dunes
somehow keep the dunes together.
The question is, okay, if these dunes are sticky,
what's causing them to be sticky?
On earth, if you want to make sand sticky,
you need to add water to help it clump together,
but on Titan, the sand comes not from rocks or shellfish,
but from Titan's exotic atmosphere.
Ultimately, it must be coming from the hydrogen
and carbon that's stored in methane in the atmosphere.
So you're basically making sand
from something that's raining out from the atmosphere.
Titan's sand is thought to be made up of hydrocarbons,
similar in makeup to plastic.
In their experiments, Josh and George compared earth's sand,
which flows freely, with polystyrene beads
standing in for Titan's sand.
And if your sand is made from something
similar to polystyrene beads,
it can easily build up a charge of static electricity,
which makes it sticky.
So, on Titan, when these winds blow, these hydrocarbon grains,
particles rub against each other and charge frictionally.
And so, when you do that, things tend to clump together.
The forces are strong.
It does provide that stickiness.
Titan was already proving more mysterious than anyone imagined,
yet scientists were still searching for something
that eluded them up till now... Surface liquid.
One day, nearly five years after Huygens landed,
one of Cassini's instruments spotted
something shining through the haze.
That is basically the sun
glinting off the sea of Kraken mare.
Kraken mare... the first alien sea ever discovered.
And Cassini soon found a host of seas and lakes
at Titan's north pole.
I mean, this could be earth.
Finally, Cassini had found the surface liquid
that everyone was expecting.
In many ways, this lake is much like
what we would find on Titan,
but in other ways, it is very different.
First of all, on Titan, the liquid is not water...
It's liquid methane,
because the temperatures are so cold
that methane cannot be a gas... it's a liquid.
The sky would not be blue.
I'd be kind of a deep orange.
Planetary scientist Jani Radebaugh
is looking at the parallels between the two worlds.
The mountains surrounding this lake are made of rock,
but on Titan,
even though the mountains would look very similar,
they wouldn't be quite as tall,
but they would be heavily eroded,
they'd have river channels,
and they are made of water ice.
And on Titan, ice is so cold that it is a solid rock.
Just as the earth has a liquid cycle,
where water changes from clouds to rain to rivers,
lakes, and seas, so Titan has one, too,
with methane taking the place of water.
This methane actually follows exactly the same cycle
that water has on earth... Evaporating from the oceans,
getting into the atmosphere, making clouds...
Clouds of methane on Titan...
Falling through the atmosphere in the form of rain...
Rain of methane on Titan.
And with surface liquid,
you find places with special significance,
the meeting point between solid, gas, and liquid... a beach.
We're thinking more and more about the importance of beaches
as a possible cradle for life on the earth.
What's so vital about a beach is you have this space
where there is liquid
interacting with solid materials,
important building blocks, and the atmosphere.
All three of those things can exist... coexist on a beach.
Those things together basically enable
the right kind of chemistry,
the right chemical conditions that may lead to life.
Tons of larvae.
Blech. Stinky.
Life on Titan's beaches is extremely unlikely,
but it offers a window
into some early pre-life processes
on our own planet.
Cassini and Huygens together lifted the veil of orange fog
and revealed Titan's treasure trove of secrets...
A moon strangely earthlike and yet otherworldly.
But it was another moon that would offer up
the most delicious of discoveries...
The tiny ice moon Enceladus.
The Cassini spacecraft's revelations
about the ice moon Enceladus blew everyone away.
They emerged initially from an unexpected source...
From Cassini's sixth sense,
it's ability to sense magnetic fields.
The magnetometer is an instrument
run from London's imperial college by Michele Dougherty.
This large boom here, which is 11 meters in length
on the main spacecraft, is where we put our instrument.
The main objective of the magnetometer
is to investigate the magnetic field generated by Saturn,
to help probe the inner workings of the gas giant.
For 20 years, data has been flowing
from Cassini's magnetometer
a billion miles away via the jet-propulsion laboratory
into this small room in London.
Coming in the back is the direct link to JPL.
Early in 2005, a stream of data arrived through these cables
that would radically change the entire mission.
In 2005, there were three planned flybys over Enceladus.
The first flyby took place on the 17th of February,
and it was a distant flyby...
1,000 kilometers above the surface.
For the magnetometer team, this was a prospect no more exciting
than any routine day's worth of data.
But hidden in the graphs was the tiniest of glitches.
You can see there's a little pimple in the data
just over there, an anomalous signature.
When I first looked at that data, I thought,
"oh, I know the spacecraft was moving really quickly.
Maybe we haven't got the trajectory right."
You know, "maybe that's why we're seeing
this funny signature in the data."
This strange signature seemed to suggest
that something on or near Enceladus
was somehow blocking the magnetic field of Saturn.
It's almost as if Enceladus is acting as a much bigger obstacle
than its physical size.
One of the ways you can do that is if you've got an atmosphere.
The other thing we noticed is, there was a lot of noise
in the data on either side.
And what we were able to do is calculate what ions
were generating those waves, and it was water-group ions.
It seemed to suggest that there was some kind of atmosphere
around the moon,
an atmosphere of water that no one had anticipated being there.
A second flyby a month later confirmed the results.
One of the reasons we waited for the second flyby is
it was really weird to see
that there was potentially an atmosphere
on the first flyby, 'cause Enceladus is small.
And so the implication was there was something generating
the atmosphere, so this was a real surprise.
That's why I was so wary about saying anything
until we'd had the second flyby,
just to make sure 'cause, you know,
you don't want to make a fool of yourself.
Michele and her team decided it was time
to alert the rest of the mission.
We knew for us to be able to have a chance of really seeing
what was going on in Enceladus, we needed to get closer.
And so we made the decision that I would go out to JPL
and try and persuade the project to take us really close.
And so, armed with her anomalies,
Michele made the journey to JPL.
It took a lot of discussion.
Not everyone was supportive.
Some of the teams would then lose some data,
because some of the planned observations of Enceladus
would have to change.
But the project talked about it, and they then decided
we would go much closer on the third flyby.
And I must confess, I didn't sleep for two or three nights
before that close flyby
'cause if we hadn't seen anything,
no one would ever have believed anything I said again.
But was we found was spectacular.
When Cassini returned to Enceladus in July 2005,
it passed just over 100 miles from the moon.
What it saw thrilled everyone.
We finally got to see the south pole of Enceladus,
and here it is.
It's crisscrossed by these major fractures.
Nicknamed "the tiger stripes,"
Cassini found that these fractures were radiating heat.
Heat... I mean, who expected the south pole of Enceladus
to be hot?
And what we found was
instead of the atmosphere covering the entire surface,
it was just focused at the south pole.
And that's not all.
Pouring out of the tiger stripes were giant geyser-like jets
spewing water vapor and ice particles
from the cracks in the ice crust.
And the discovery of the plumes has revealed
the origin of Saturn’s outermost ring...
A ghostly ring called the "E" ring.
Something like, would be 200 kilograms
a second of predominantly water-ices
is thrown out into space.
So, what it does is form a ring, and that's the "E" ring.
The question was, where was the water coming from?
We have been able to determine there is a large water pocket
or sea, deep sea,
under the south pole of Enceladus.
It's about the size of lake superior in north America.
Based on this discovery,
many more visits to Enceladus were planned.
The closest flyby was within just 16 miles of the surface.
And by the time we did that one, we were very confident.
So we flew in on thrusters 'cause we didn't know
what Enceladus would do to us.
And then you were getting, like, one thruster pulse.
In the process of getting good at it,
they used up all the propellant,
'cause you really don't have much choice.
But, no, I think they've been very good at it for a long time.
It's just that now, some of these flybys
are just exquisitely accurate.
So accurate and so close
that Cassini was able to taste the spray,
and what it found raised an extraordinary possibility.
This is not one of the places in the solar system
where people think potentially life
might have formed in the past
or might be able to form.
I love this picture,
and it's about as much meaning as you can get
out of the Cassini mission
because we know that that moon has an ocean in it
that could harbor life.
If life evolved on that sealed ocean,
then it must have evolved
separately from life on our planet.
It would be a sign of a second Genesis.
I think that all we need to do is find that life
has independently arisen, just one other time.
And that would tell us that it's everywhere.
If it happened a second time, it probably has happened,
you know, a colossal number of times throughout the cosmos
and throughout its history.
But sadly, ironically, it was this greatest discovery
of Cassini's that ultimately sealed its fate.
After 20 years, the great explorer is running out of fuel.
And when the fuel is gone,
so, too, is NASA's ability to steer the spacecraft.
We didn't want to lose control of Cassini
and have it crash on the surface of Enceladus.
If you discovered life there one day,
there might be those doubters who would say, "yes,
but a spacecraft crash landed and took bacteria there."
And so, the mission time decided to use the last drops of fuel
to set Cassini on a final phase
that would take it closer and closer to Saturn
before plunging into the planet and being destroyed,
a phase NASA called "the grand finale."
Ansco systems, Cassini Ace station is currently looking
for the X-band one-way carrier signal.
In April 2017, mission scientists gathered
at NASA's JPL to witness
the beginning of the end for the Cassini spacecraft.
There's a real buzz here of excitement
and, you know, slight nerves, as well.
The reason it's so exciting is
this is the start of the end of the mission.
We're running out of fuel, and we're going to make sure
we go out with as much great science as we can.
The last phase of the mission known as "the grand finale"
began with a hair-raising dive
through the gap between the rings
and the cloud tops of the planet.
It's risky, but with the mission coming to an end,
the team could afford to take risks
that would previously have been unthinkable,
and send the spacecraft
exploring closer to Saturn than ever before.
Everything looks great.
We're just now waiting for the data.
It was worth the risk, because flying inside the rings
will allow the team to explore enduring mysteries
such as the mass and the age of the rings,
the exact length of Saturn’s day,
and in its final moments,
the actual composition of the atmosphere.
Ansco systems, Cassini
Ace, I can confirm science playback is in lock
and is starting to run.
The green spike was the first sign
that Cassini survived the dive
and was now sending data back to earth.
The grand finale consists of 22 of these hair-raising dives
between the rings and the planet
before the final plunge into Saturn’s atmosphere.
From this unique vantage point, Cassini has already sent back
these images from the atmosphere
taken on the very first dive,
merged here into a slice of Saturn
taken from closer than ever before.
Analyzing images such as these
will keep scientists busy for years.
And this, the first-ever series of images
showing the rings from the inside looking out.
It's coming in right now.
Yeah, we are at about two hours before the plunge.
Critically, for those final moments of the mission,
Julie must ensure that Cassini is able to collect
and transmit data till its dying breath.
So, what my team is doing right now is simulating
the last four hours of Cassini's life.
We've cleared off the solid-state recorders.
We've dumped down all the pictures.
All we're doing is as much real-time data as we can.
Data can only be sent as long as the antenna
is pointing precisely at the earth,
something that will get increasingly difficult
as Cassini starts to be buffeted by Saturn’s atmosphere.
So, what we do is we let the spacecraft go
until it hits the... Deadband
and then it fires the thruster to push it back,
and then we let it drift over to other side.
So it's called bang-bang controlling.
It doesn't know it's in trouble yet.
Right now, they're firing once every, you know, minute or so.
And then as they get into the atmosphere,
they'll start firing more and more
and more and more in the last few minutes.
And what we want to see is we want to see how much of
the atmosphere we can see before we lose the signal,
before it can't fight the atmosphere anymore
and it goes off-point.
And then, at that point, it starts to burn up.
It goes from 200 to 2,000 degrees
in just a matter of seconds,
and then everything will start to melt and disintegrate.
And then it'll go away.
It just... We'll lose the signal,
and that'll be end of mission.
So pretty much everybody will know at the same time,
the end of mission,
'cause we'll all see the carrier signal go away.
Yeah.
So after dedicating nearly three decades of your life
to a spacecraft, how do you say goodbye?
The Cassini-Huygens scientists and engineers
have faithfully dedicated
over two decades of their lives to the mission.
And now, it's nearly time
to say farewell to their beloved friend.
My navigation team will be sitting up here.
I will be out in Pasadena.
I've spent 20 years of my life on this.
And back here, radio science is going to be one
of the most critical positions,
because they'll have the open-loop receivers,
and they'll be the very last signal.
Cassini's going to be getting and transmitting data
to its last breath.
I'm going to cry my eyes out.
I cried when it launched.
Everybody will be watching the spacecraft,
making sure that we're getting all the data.
This'll have a cast of thousands.
Every seat will be taken.
Project manager... I usually like to sit next to Earl,
so Earl will be here.
I'm in the flight director's seat.
Flight director systems lead, everything is nominal.
Copy.
Spacecraft has just crossed 10 degrees north latitude,
altitude 1,000 miles.
In its final, fatal kiss...
We just had the transitions high-rate mode,
and we are in the atmosphere.
Cassini touched Saturn’s atmosphere,
and then began to burn up,
becoming part of the very planet it had got to know so well.
Oh. Oh.
At exactly 4:55 and 46 seconds pacific time on Friday,
the 15th of September, the signal disappeared.
That would be the end of the spacecraft.
Project manager off the net.
And Cassini,
unquestionably one of our most successful missions into space,
came to a final spectacular end.
It's a 20-year-old friend.
I can't imagine anything topping that,
but we will try for a new mission.
It's always that way.
It's like a death in the family, you know?
It's imminent, but when it happens,
it's the finality of it that really is what you're left with.
Cassini may be gone, but its revelations will continue.
Results are already starting to emerge
from the grand-finale orbits.
And we could be a step closer
to discovering the length of Saturn’s day
by pinning down the mysterious tilt of its magnetic field.
If there is a tilt, it is really small.
But we need to find that tilt if we're going to work out
how long a day on Saturn is.
I would think we would probably have a final launch
in three to six months.
It's mission accomplished.
And for us, it was a long, long mission.
It was totally appropriate that it was slightly
raining here as we walked out
'cause you know, I think even the earth is crying right now.
That was a great spacecraft.
It did exactly what we asked it to do, all the way to the end.
No surprises.
And the legacy of Cassini
looks set to continue long into the future.
Scientists will be pouring over our images
and all the data from Cassini for...
I mean it... 100 years.
We got this amazing amount of information
to pass on to future generations.
We've only skimmed the surface of what's in that data.
Godspeed, you know.
Been a great spacecraft, a great program, you know,
thank... Thank it and release it.
In its dying hours, Cassini left us with these final pictures.
This is its last-ever image.