- 3 months ago
Chronicling the story of NASA’s Cassini mission, this is the latest in our series of documentaries, “JPL and the Space Age.” These films use rare archival footage and interviews with pioneering engineers and scientists from the Jet Propulsion Laboratory in retelling of many of humanity’s first steps into the cosmos.
Other films in this series are available for viewing at https://www.jpl.nasa.gov/who-we-are/d.... Part I of this two-part story premiered here on Oct. 15, 2021. Both parts of “Triumph at Saturn” are planned to be added to this collection in the near future.
Other films in this series are available for viewing at https://www.jpl.nasa.gov/who-we-are/d.... Part I of this two-part story premiered here on Oct. 15, 2021. Both parts of “Triumph at Saturn” are planned to be added to this collection in the near future.
Category
📚
LearningTranscript
00:00:00Goodbye, Cassini, your mission's fini, Bravo, Cassini, have some linguine.
00:00:23You showed us Saturn's rings and lots of pretty things. Huygens' probe took a dive early 2005. Landed on Titan, it was excitin'. Your mission never failed to surprise, dazzled our eyes.
00:00:50Now, dive to Saturn, vaporize.
00:01:03In 1997, an ambitious international mission launches to Saturn that would, for the first time, attempt to place an orbiting spacecraft around the planet and land a probe on a moon in the outer solar system.
00:01:17But it was a mission that had to fight its way just to reach the launch pad.
00:01:24Our Congress has had some agony over the program. We're going to have to operate under a very strict fund ceiling and an unyielding schedule.
00:01:32We are all going to have to strive for, as we go through this process, a continual search for the least unacceptable solution.
00:01:39The journey to Saturn took seven long years. And being captured into orbit depended on what would happen during just three hours.
00:01:47We chased everything that could go wrong down the rabbit hole. We went down every path of, if this goes wrong, what do we do? If that goes wrong, what do we do?
00:02:02All stations on that, SOI systems. Just an advisory. We're coming up on the time that the critical sequence will initiate the turn to the SOI burn attitude.
00:02:11This was one of those moments where you're either in orbit or you're a billion-dollar flyby.
00:02:16Flight, it's welcome. Go ahead, it's welcome.
00:02:20The Doppler has flattened out.
00:02:28With Cassini safely in orbit, science quickly took center stage, beginning with dazzling images of Saturn's rings.
00:02:36I'm surprised at how surprised I am at the beauty and the clarity of these images. They are shocking to me.
00:02:46Investigating Saturn's iconic rings will be just one part of what will turn out to be 13 years of discoveries about the Saturnian system.
00:02:55And what will be realized about Saturn's moons will even transform how we think about our solar system and open up new pathways for the future of space exploration.
00:03:14Around one planet, we find two moons that could potentially have the key ingredients to support life.
00:03:21Triumph at Saturn, next.
00:03:40For some scientists, the Saturnian moon Titan has been a higher priority for exploration than even Saturn or any other planet.
00:03:49That's because Titan may resemble what Earth was like billions of years ago.
00:03:56Making this moon a kind of time machine that preserves in deep freeze many of the conditions that led to life on our planet.
00:04:06Titan is the only moon in our solar system having a dense atmosphere made mostly of nitrogen, just like the Earth.
00:04:13There are smaller amounts of methane and ethane that break down into organic compounds, creating the moon's smoggy orange haze.
00:04:24Titan's extremely cold temperatures turned some gases into liquids, which led scientists to wonder, could Titan have oceans made not of water, but of liquid methane and ethane?
00:04:36These questions made the unmasking of Titan a major objective of the Cassini-Huygens mission.
00:04:47And before the release of the Huygens probe, Cassini would have the first opportunity to see this moon close up.
00:04:53With hopes sky-high that the spacecraft might see Titan's surface, scientists were eager to share the five-hour-plus flyby live with the world.
00:05:06And you're watching live coverage from the Jet Propulsion Laboratory in Pasadena, California.
00:05:15Tonight, the Cassini spacecraft has its first close encounter with Saturn's largest and most intriguing moon, Titan.
00:05:24This is the closest we have ever been to Titan, and over the next five and a half hours, we hope to see the best images we have ever seen of Titan.
00:05:32And here on NASA TV, you will see those images just minutes after they actually arrive on the ground.
00:05:39And right on cue, the images began streaming down.
00:05:44But it quickly became apparent that Titan wasn't ready for its first close-up.
00:05:49We have just received exciting word that we have the first image in.
00:05:54Okay, so this looks like, um, wait.
00:05:58Boy, it takes a bit of processing to bring out features.
00:06:04What appeared at first glance to be black and white smudges left scientists and viewers alike puzzled as to what they were seeing.
00:06:14Look at that. Look at that. And we don't know what it is.
00:06:17Anything stand out in your mind at this point?
00:06:23Yeah, it's been a very strange evening.
00:06:26If you, uh, put me against a wall and said, what's cloud and what isn't cloud, I really couldn't tell you.
00:06:31I assume that much of this is surface features.
00:06:34Yeah, these are, um, low contrast, not really sure what we're looking at here.
00:06:38With us now is Torrance Johnson, one of the imaging scientists, to kind of give us the overall what does it mean?
00:06:48Well, I think, uh, first off, the, uh, the main thing that tonight's meant for us is we've had a very successful encounter.
00:06:55We're, uh, really looking at a great haul of data here.
00:06:59And, um, well, you saw some of this stuff coming in. There's clearly stuff to be seen there on that surface, understanding it's a different issue.
00:07:08And, uh, one of the things that all of us on the project have been talking about for a long time is this sort of cooperative science approach.
00:07:17We knew Titan was a tough target, was going to hold its secrets tightly, and so we designed this mission and the experiments to hit it with everything we've got.
00:07:26This is our first chance to do that, really.
00:07:30We're really going to have to do a full-up, complete body scan of Titan to figure out what's going on.
00:07:38This encounter confirmed that Titan would be as complex as it was obscure.
00:07:44Fortunately, there are many more Cassini flybys still ahead.
00:07:48But next up to explore Titan is the European Space Agency's Huygens probe that will try to descend all the way to the moon's surface.
00:07:59Uh, the procedure here is pretty standard. We're going to follow right through the MOP.
00:08:04Uh, the idea is a series of brief reports from...
00:08:07Eight weeks have passed, and it is the eve of Christmas Eve, as leaders of the Cassini Huygens team hold a go, no-go meeting on whether to release the Huygens probe.
00:08:20We had two opportunities to update this, one at the Titan flybys.
00:08:24There are no known technical issues with which to contend, making this meeting mostly a formality.
00:08:29In cleanup, navigation has flown a precision trajectory, so there was no need for us to make any updates.
00:08:36Um, tracking data has been absolutely excellent lately. DSN has been doing a really good job.
00:08:41And Julie's team has been doing a marvelous job. She has given us recently really great maneuvers, so, without that...
00:08:48Yeah, don't, don't jinx it, Jerry. Don't jinx it.
00:08:52I'm just raising by the extent that they're the pagers.
00:08:54There go the pagers.
00:08:55I know, yeah.
00:08:57It's a joke because the pager goes off.
00:09:02Based on what we've heard here from the representatives and the people that did the work,
00:09:07it's very clear that the orbiter JPL part of this team is ready to proceed.
00:09:14The probe, the probe, the probe team is also ready to go, so we are green for tomorrow.
00:09:20So let's go.
00:09:21Okay, well, let me just add my enormous thanks from the European side for the terrific collaborative effort on the U.S. side.
00:09:34It's just been great to be working with you, and I think we're all very appreciative, and so let's go.
00:09:40Okay, we are a go. We're good.
00:09:48Southwood's remarks were heartfelt, as four years earlier the mission had faced what seemed an unsolvable problem.
00:09:56A design flaw found on Huygens' receiver located on the Cassini spacecraft.
00:10:02An in-flight test revealed the receiver was incapable of adjusting to Doppler shifts, changes in radio frequencies.
00:10:10That would leave Huygens' data nearly worthless.
00:10:17A major fix required a hands-on solution, impossible to do with the probe a billion miles away.
00:10:25Knowing little could be done to Huygens, the best hope rested with Cassini, when mission planners realized that adjustments to the spacecraft's trajectory could minimize radio frequency changes.
00:10:38This required Cassini to fly higher above Titan and at a relatively slower speed, which would allow the data to be accurately recorded as the probe descended.
00:10:52But this solution was not free. It would cost Cassini a quarter of its reserve fuel.
00:11:02This sacrifice confirmed that Cassini-Huygens was truly an international partnership.
00:11:08For without this decision, Huygens was assured of being seen as a failed mission.
00:11:13The crisis was now only a memory, and it was now time for the probe to detach from Cassini to begin its dangerous descent into Titan.
00:11:25There's a JPL saying that for some celestial reason, major mission events always seem to happen on holidays, weekends, late at night, or a combination of the three.
00:11:49The probe's release is no exception to the rule. It is Christmas Eve.
00:11:56I'd like to start the poll in five minutes.
00:12:00On hand to show their support for the Cassini team are leaders of the Huygens probe, JPL director Charles Alaci, Caltech president David Baltimore,
00:12:12and arriving just in the nick of time, JPL veteran Tom Gavin, whose job title includes the phrase, mission success.
00:12:22Looking like cutting it close.
00:12:24Nothing like, well.
00:12:25Before you lost signal.
00:12:26I knew you would have under control.
00:12:29Right?
00:12:30Yes, sir.
00:12:31He came for when he received the signal. That's the important signal.
00:12:33Got it all.
00:12:35When will they acquire the signal, do you think?
00:12:37Earliest carrier lock is 749.
00:12:52That's right on the money.
00:12:53Right on the money.
00:12:54Right on the money.
00:12:55Right on the money.
00:12:56Exactly.
00:12:57Woo-hoo!
00:12:58Released.
00:12:59All three.
00:13:00All right.
00:13:01Woo-hoo!
00:13:02Woo-hoo!
00:13:03Woo-hoo!
00:13:04Woo-hoo!
00:13:05Woo-hoo!
00:13:06Woo-hoo!
00:13:07We see a big...
00:13:08Okay, you're on your own now, you know.
00:13:13With the Huygens probe now on its own, silently free-falling to Titan for the next 21 days, the Cassini team
00:13:21can relax and enjoy the holidays, especially New Year's Day.
00:13:28That was because JPL was sponsoring a float in the Pasadena Tournament of Roses parade for only the third time in the lab's history.
00:13:39The float featured nine JPL missions.
00:13:42The one at the top was Cassini.
00:13:51The Huygens dive into Titan is the most distant landing ever attempted.
00:14:11The descent through the atmosphere is expected to take more than two hours.
00:14:18The hope is that the probe's batteries will last long enough to reach the surface.
00:14:25What it will be like, no one really knows.
00:14:29Because there could be lakes or seas of methane, the probe has been designed to float.
00:14:36But first, Huygens has to survive the plunge through Titan's atmosphere.
00:14:51The entry speed is more than 12,000 miles per hour.
00:14:57Soon temperatures are soaring over 3,000 degrees Fahrenheit.
00:15:01If the heat shield does its job, the science instruments inside the probe will have no idea there is an inferno taking place just inches away.
00:15:11After surviving the initial phase of the descent, the first of three parachutes deploys.
00:15:30Nearer the surface, the winds begin to calm and Titan's orange haze begins to clear, revealing below a surreal landscape.
00:15:49So imagine descending down through a misty, cloudy atmosphere and suddenly below you breaks this vista of this very bright hill with channels that are carved by liquid,
00:16:08with rounded pebbles that were evidently rolled and tumbled by liquid.
00:16:12That was what the Huygens probe saw and it showed us that methane not only is in the atmosphere but has been raining and producing weather and carving features in the landscape for long periods of time.
00:16:25As Huygens lands in a triumphant plop, history is made.
00:16:43And better yet, the probe's batteries are still working.
00:16:48What Huygens sees seems to resemble a dried up riverbed.
00:16:55Right in front are rocks made of frozen water harder than stone.
00:17:01There are no signs of lakes or seas.
00:17:06But Huygens view is only a single spot on a moon larger than the planet Mercury.
00:17:12The global reconnaissance will come from Cassini.
00:17:15On many of Cassini's orbits around Saturn, the spacecraft will fly near Titan,
00:17:29allowing navigators to use the moon's mass to alter trajectories while at the same time conserving fuel.
00:17:37These flybys are also opportunities to use Cassini's powerful radar to penetrate through swaths of the moon's hazy atmosphere.
00:17:47The radio waves that bounce back from Titan's surface can be turned by scientists into topographical maps.
00:17:56Piece by piece, swath by swath, Titan is revealed.
00:18:02Let's start at the beginning and run to the end and just see what interesting things we see and maybe you can point out the things that you've seen too.
00:18:08Okay, here is the new swath as it comes through here.
00:18:12Titan really is in some ways a kind of a cosmic striptease act because we can't see the surface in the normal wavelengths that our eyes would use.
00:18:22And the radar operates by making images in narrow strips.
00:18:26And so strip by strip in different places, Titan has been unveiled.
00:18:30Here, can everyone see?
00:18:32In that slide, you can see a feature that runs almost perpendicular to the altimetry track.
00:18:37So we see the end of the dunes here.
00:18:39Then you see the dunes peter out and they get brighter, which is interesting here.
00:18:44Massive dunes are seen, made not of sand, but of organic molecules containing carbon.
00:18:52From the email traffic last night, I sort of gathered nobody sees a magic island in the data that we have, correct?
00:18:59I think that's correct.
00:19:01Tell you what, you want to zoom in on the beginning of that?
00:19:04A large dark basin turns out to be a lake full of methane.
00:19:11It is the first of hundreds of deep lakes and seas that will be found.
00:19:17Most of the observation of this lake, they show a subsurface reflection.
00:19:23So the depth of this particular lake is about 100 meters, as we can see from the axis of the image.
00:19:30Is it right to get out of this that the small lakes don't seem to be any shallower than the larger lakes?
00:19:36Titan's strangest discovery is a continent-sized area named Xanadu.
00:19:42Here are canyons and mountains that resemble no other place on this moon.
00:19:49It is as if, one scientist said, it's from another world.
00:19:55One thing, just to make a quick comment, is that I am always very impressed by the radar planning team.
00:20:02They absolutely got it right on the bullseye, because this is, you know, a long way away, flying by kilometers per second, and they put it right on the bullseye. Nice job.
00:20:15Titan may even have volcanoes that gush out an icy mixture of water and other materials.
00:20:23And this water comes from a hidden ocean beneath Titan's icy shell.
00:20:32And whenever water is mentioned, it's not long before the question is raised,
00:20:37is this a place that could possibly support life?
00:20:42Giant Titan, the size of the planet Mercury, has a global liquid water ocean underneath its icy crust,
00:20:49as well as methane lakes and seas at the North Pole.
00:20:53And we wonder, could those methane lakes and seas support a different kind of life?
00:20:59So that's really opened our eyes.
00:21:04There's still more that was discovered.
00:21:07This moon has weather and seasons.
00:21:10Here it rains, not water, but methane that floats down like snow.
00:21:17It's so Earth-like that this is a very familiar place.
00:21:20The chemistry in the atmosphere is much more complex than expected.
00:21:25And the system as a whole is just as intricate as Earth in terms of the atmosphere interacting with the surface and the materials on the surface.
00:21:36Titan has a methane cycle just like Earth has a water cycle.
00:21:39And being able to watch that in action, seeing the lakes on the surface, the channels that have been carved into the surface,
00:21:46and then actually seeing clouds forming in the atmosphere and rain, the effect of rain on the surface.
00:21:51That whole cycle has been one of the things that's been absolutely spectacular.
00:21:55Saturn's moon, Enceladus, was also a target of special interest for Cassini.
00:22:02It is the most reflective object in the entire solar system.
00:22:11And a great mystery was why this moon seemed to have so few craters.
00:22:14Theories abounded.
00:22:15Might there be some internal heat source that melts ice on the surface, which then fills in the holes?
00:22:21Could volcanoes or geysers account for the moon's shiny façade?
00:22:22Or was Enceladus just a dead, airless ball of ice?
00:22:23It is the most reflective object in the entire solar system.
00:22:28And a great mystery was why this moon seemed to have so few craters.
00:22:34Theories abounded.
00:22:35Might there be some internal heat source that melts ice on the surface, which then fills in the holes?
00:22:41Could volcanoes or geysers account for the moon's shiny façade?
00:22:46Or was Enceladus just a dead, airless ball of ice?
00:22:53Cassini would find the answer, sending shock waves through the scientific community.
00:22:59All of it brought about by one of the spacecraft's least known science instruments.
00:23:05The spacecraft's magnetometer.
00:23:08It's a kind of high-tech compass that makes measurements of magnetic fields.
00:23:14It's so sensitive that it can even detect the spacecraft's own magnetic emissions.
00:23:20To cancel out those unwanted signals, this instrument was marooned out on the end of Cassini's long boom.
00:23:28On this flyby, no one was expecting there would be much from the lonely instrument.
00:23:35I must confess, we weren't expecting to see anything.
00:23:38And so we didn't look at the data for a couple of days.
00:23:41And then when we went in and looked at the data, only magnetometer people can get excited by our data.
00:23:49Because you sort of plot it on a scale where you look at the whole day.
00:23:53And we had a look at the wiggles on the plot, and they looked strange.
00:23:58The expectation was that Saturn's magnetic field would extend straight out and flow directly through Enceladus.
00:24:06Instead, the magnetic field was curving around the moon.
00:24:11There were also unexpected signs of ionized water vapor molecules.
00:24:17These were measurements that could be translated into sounds as the spacecraft approached and departed from Enceladus.
00:24:24And so it was clear that there was a source of water group ions in the vicinity of Enceladus.
00:24:43And in addition to that, there was something strange going on in the magnetic field.
00:24:47It looked as if Enceladus was a much bigger obstacle to the flow of plasma and field coming from Saturn.
00:24:54It was almost as if the magnetic field of Saturn and the plasma of Saturn were being stood off from the surface of the moon.
00:25:01Unsure of the accuracy of the data, Dowardy and her team awaited the results of a second, closer flyby.
00:25:08And I must confess, we looked at that data straight away.
00:25:13We were a little concerned about the calibration of the instrument,
00:25:17but that there seemed to be something in the data which was pointing to an atmospheric signature of some kind.
00:25:27And at that stage, we were talking about an atmosphere covering the entire surface.
00:25:31Not everyone on Dowardy's team agreed.
00:25:36For one thing, tiny Enceladus lacks enough gravity to hold an atmosphere in place.
00:25:44In hopes of solving the mystery,
00:25:46Dowardy proposed flying even closer to Enceladus on the next flyby.
00:25:51Doing so would upset trajectory and science plans long ago mapped out.
00:25:56But Dowardy's argument won the day.
00:25:59Navigators plotted out a new course that sent Cassini skimming just over 100 miles above the moon.
00:26:08For the couple of nights before that flyby, I didn't sleep.
00:26:11What happened if we had seen nothing at all?
00:26:13No one would ever have believed anything I said again.
00:26:16And I didn't sleep well at all.
00:26:18But then we got the data back.
00:26:20And it was spectacular.
00:26:22In the southern polar region,
00:26:25Cassini found the landscape free of craters,
00:26:28yet littered with house-sized boulders of ice,
00:26:31carved out along bluish trenches that scientists dubbed tiger stripes.
00:26:40The moon would no longer be known for being smooth.
00:26:43Here was a fractured surface,
00:26:45containing criss-crossing faults, folds and ridges.
00:26:50These crevices tell us that Enceladus is geologically alive.
00:26:59From these fissures more than a mile deep, geysers are erupting.
00:27:08Nicknamed Cold Faithful,
00:27:10they are continuously spraying out massive jets of ice particles and water vapor.
00:27:22The speculation from more than a decade before,
00:27:25that the shiny surface of Enceladus might be the result of ice volcanism turned out to be true.
00:27:31A momentous discovery that began with unusual wiggles on a chart.
00:27:36I thought, OK, my reputation is saved.
00:27:42They're not going to think I'm crazy.
00:27:44But also, it made me feel really proud of what magnetometer instruments can do.
00:27:50Because, you know, in some ways, because we're just wiggly data on a plot,
00:27:55it's very hard to get people enthused by our data.
00:27:59You saw the media geysers as well.
00:28:01It's really difficult to enthuse you.
00:28:06The detection of geysers was stunning,
00:28:08for it meant the existence of liquid water near the surface of this bitterly cold moon.
00:28:13And that turned Enceladus, in an instant, into a prime target for the remainder of the mission.
00:28:32Previous plans were tossed aside in favor of adding more Enceladus flybys,
00:28:37including dramatic plunges through the plumes.
00:28:50What is that?
00:28:52And look at this little thing here, this circular feature.
00:28:56It's so complex.
00:28:58The question is, are both of them coming out of the tire stripes?
00:29:02It would be nice to get a temperature measurement right on that.
00:29:07Look at that. It looks almost like a river.
00:29:11See, that's in shadow, but we can still see because the moon is so bright.
00:29:15There's so much multiple scattering.
00:29:20Enceladus is as small as it is bright.
00:29:25This small when compared to Earth and our moon.
00:29:28Given its diminutive size, it was thought Enceladus would have long ago lost any interior heat.
00:29:40And what, scientists wondered, was causing Enceladus' plumes to spray out these hotspots?
00:29:47The answer involves Saturn's massive tidal forces.
00:29:51They create friction inside the moon's interior, where there exists an ocean of water.
00:29:58A tremendous discovery.
00:30:00And liquid from this ocean wells upward, creating the moon's hotspots.
00:30:07And the geysers that vent out.
00:30:09And from these plumes, scientists discovered that the moon's ocean contained salts and complex organic molecules.
00:30:22Likely created by hydrothermal vents.
00:30:26The exact conditions believed to have given rise to life on Earth.
00:30:30For many, these discoveries about this tiny moon was Cassini's biggest triumph.
00:30:40For Enceladus is now one of the most promising destinations to search for life elsewhere in our solar system.
00:30:47Cassini's discoveries during the first four years at Saturn raised new questions to answer.
00:31:10With the spacecraft in excellent health, NASA twice extended the mission's funding.
00:31:19Over the course of 13 years, the spacecraft orbited Saturn 294 times.
00:31:27No two orbits were alike.
00:31:30Determining the pathways for these intricate loops is the work of true rocket scientists,
00:31:36or as they are called, tour designers.
00:31:41They are mathematical wizards who charted courses through the maze of Saturn's 80-plus moons and its ring system.
00:31:51That is half of the job of these three tour designers.
00:31:56The other half, trying to please 200 scientists.
00:32:00This tour is probably a yellow, because I hate to keep having this email exchange back and forth.
00:32:04It looks bad, I think.
00:32:07We're taking in all the science requirements, which are, you know, could be a stack that thick.
00:32:13We're kind of like a tour guide bringing a big group of kids, or scientists, to Disneyland.
00:32:19And the only problem is we have to stick together as a group.
00:32:22We all have to do the same thing.
00:32:24And it's, again, trying to please everyone equally, or as my old supervisor said, equally unhappy.
00:32:31If everyone's equally unhappy by the end of the tour selection process, then we've done our job.
00:32:38You can see that all of the tours have a large number of southern hemisphere coverage.
00:32:43We have evaluated the nominal tours that came out last week.
00:32:52Any modifications are things that we're going to have to grapple with as a group.
00:32:56This, we can't have an input that's a mix of the two unless we all understand all of the implications.
00:33:03Hey guys, can I interrupt for a minute?
00:33:04Can I interrupt for a minute?
00:33:06They debate it out, they listen to each other, it gets heated at times.
00:33:09Is that a reasonable approach?
00:33:12That's what I would, I would like to see.
00:33:14But I have an objection to that.
00:33:16Are we making the right choice for the right reasons?
00:33:19Well, that's, every team is going to have to think about that, because we're not going to do the allocation until after the tour is selected.
00:33:26So, in a sense, you are taking that risk.
00:33:29It can be very frustrating at first, because in one meeting someone will say,
00:33:32well, do A, you've got to do A.
00:33:33In the next meeting they'll say, oh, you can't do that, you have to do this instead.
00:33:37Just a strategic comment, I think everybody in this room knows how rushed the evaluation of all these tours were, because they came in so late.
00:33:46It starts out, everybody's on different ends, sometimes yelling, sometimes red-faced, really mad, like they're really trying to make sure they get heard.
00:33:53The tour designers have been looking at what is the flexibility in a given tour to raise and lower the altitude.
00:34:02You know, we have to look at the ripple effect.
00:34:05When you're up high, out of the orbit plane, you're up way above sight and you get a good view of the rings, but you're not around any of the other moons.
00:34:12And so the people that want to look at the rings want to be up high and look at the rings.
00:34:16The other people want to be down in the same plane with the rings, where they can visit all the other moons.
00:34:20And that's a huge tug of war.
00:34:21You know, it's such that the J2 perturbations are maximized.
00:34:24What you're hearing here, and I said it earlier, what you're hearing from the people in this room from the science side, they haven't had a chance to really evaluate the information in a way well enough so they think we've got the right decision.
00:34:37We had went through the stressful times earlier in the week, you know, meeting with each discipline working group because, you know, we sit in front of these, you know, 40 or 50, you know, world renowned scientists in a specific field.
00:34:50And it's kind of like a congressional hearing where they just fire off questions, you know, one after the other.
00:34:55You really have to know your stuff and understand every new secrecy of each specific tour.
00:35:00But after they got hurt, I mean, people kind of calmed down a little bit.
00:35:03But eventually everybody gets like, yeah, that's kind of the best thing.
00:35:06So we're very lucky that the spacecraft is very highly functional and we have a lot of fuel.
00:35:11All the tours are good and I'd feel happy if any of them got selected.
00:35:15I mean, all of them are going to be really exciting.
00:35:18I mean, just, I mean, just amazing pictures.
00:35:23It's almost like we have Ansel Adams riding on the spacecraft.
00:35:26I'm talking about pictures, but I mean, the other stuff is, is, is neat too.
00:35:32I mean, some of these instruments, they can just take a picture and they can tell you what it's made out of.
00:35:37It's like some sort of Star Trek thing, you know, but really Star Trek didn't have instruments this cool, you know.
00:35:42They just had this like green ray knee or, you know, and it did everything, right?
00:35:46Their tricorder or whatever.
00:35:47Or the really amazing stuff is when they find something that's like, they have no idea.
00:35:51They have like a, Iapetus, that, that ridge.
00:35:53Iapetus, it's like the equator is actually marked.
00:35:56It's like when I was a kid, I had a globe that got messed up and the equator kind of stuck out.
00:36:00I mean, that's, that's the way Iapetus is.
00:36:02There's this mountain ridge right along the equator.
00:36:03It's so bizarre.
00:36:12This meeting was only one of several taking place.
00:36:16It is at this larger gathering where the proposals of the tour designers, representing a year's worth of work with little time off for weekends and holidays, will be judged.
00:36:27Compared to the usual agenda, today is turned upside down.
00:36:31And the reason for that is, tour design is the main topic of this whole meeting.
00:36:39You'll notice that there's some filming or video going on.
00:36:44This is a JPL activity to document how decisions are made on projects.
00:36:55And, well, they have a cutting and editing process.
00:36:58So, I'm not sure that we'll recognize it necessarily when it's any case.
00:37:03It's like the worst take home final ever invented.
00:37:06You have 200 professors, you know, and the hardest questions you can think of.
00:37:10I mean, you're just kind of slogging through it, trying to get it done, and then you hand it in.
00:37:14PF7-11, they're both very much like 6 and 6H9.
00:37:19It kind of feels good to have it handed in, but you're not really awake enough for really much of emotion or anything.
00:37:24So, you end up with a Titan flyby at Apoapsis, and, or at Periapsis.
00:37:30And then you come back, then you do a pie transfer, then you crank up again.
00:37:33So, there's a lot of inclined time in this, and when it comes down...
00:37:37From an infinite number of possibilities, the tours are whittled down to nine.
00:37:42Next, the science teams are to rank them as green, acceptable, yellow, partially acceptable, or red, not acceptable.
00:37:51But it sounds like 6H9 and 8 should either both be, um, both be red or both be yellow.
00:37:57But wanting more wiggle room, scientists introduce a new color to the voting, lime.
00:38:04Okay.
00:38:08Uh, 6H9, three greens, a lime, and a red, uh...
00:38:12I mean, it's kind of like our job was over, just waiting to hear the result.
00:38:15I mean, I guess it's kind of like the jury coming in, but you're too tired to care what your sentence is.
00:38:20So, you're talking about PF9 for Titan?
00:38:22Eventually, a consensus is reached.
00:38:24No doubt the winning tour has left the scientists equally happy and unhappy.
00:38:37The tour designers are just plain happy.
00:38:39For the first time in a year, they will have their lives back.
00:38:43It's done. It's over. The decision's been made.
00:38:47You know, we were happy, but also just absolutely felt like your truck had run over you.
00:38:53...
00:38:55Hello, this is Arthur Clarke, joining you, from my home.
00:39:14home in Colombo, Sri Lanka.
00:39:18I am delighted to be part of this event to mark Cassini's flyby of Iapetus.
00:39:24When science fiction writer Arthur C. Clarke wrote the classic
00:39:282001 A Space Odyssey, he chose for the book's final scene,
00:39:33Saturn's Moon, Iapetus.
00:39:36As you know, I have more than a passing interest in Saturn.
00:39:41In the movie version of 2001, the ending scene was changed to Jupiter.
00:39:48But for Clarke, Iapetus remained a place of deep mystery.
00:39:53He shared his enthusiasm for Saturn's third-largest moon with those
00:39:57who gathered in JPL's auditorium to witness images of Iapetus as they first arrived.
00:40:04This is a particularly exciting moment for fans of 2001 A Space Odyssey
00:40:09because that's where the lone astronaut Dave Bowman discovers the Saturn monolith,
00:40:16which turns out to be a gateway to the stars.
00:40:20More than 40 years later, I can't remember why,
00:40:23placed the Saturn monolith on Iapetus.
00:40:26But I've always had a strange fascination for Saturn and its family of moons.
00:40:31By the way, that family has been growing at a very impressive rate.
00:40:36When Cassini was launched, we knew of only 18 moons.
00:40:41I understand it's now 60 and counting.
00:40:44I can't resist the temptation to say, my God, it's full of moons.
00:40:50So I'm going to keep my fingers crossed with what Cassini discovers at Iapetus.
00:40:57I want to thank everyone associated with this mission.
00:41:00Science projects are tremendously important for our understanding of the solar system.
00:41:05And who knows, one day, our survival on Earth may depend on what we discover out there.
00:41:13This is Arthur Clarke wishing you a successful flyby.
00:41:18What Cassini saw at Iapetus was breathtaking.
00:41:39Many of the observations focused on examining a mountain ridge on the equator
00:41:45that contributes to the moon's unusual walnut-shaped appearance.
00:41:54These mountains, made mostly of ice, are among the tallest in the solar system,
00:42:00soaring 12 miles high, more than twice that of Mount Everest.
00:42:06Scientists have more than one idea as to how they may have formed.
00:42:10One thought is that perhaps when Iapetus was more fluid
00:42:14or pliable, it was spinning very, very fast.
00:42:17And so it sort of bulged out at its equator as it was spinning.
00:42:21And as it cooled off, then it held that shape,
00:42:25actually had that mountain range going around it.
00:42:29While the bulge remains to be solved,
00:42:32scientists believe they are on more solid ground
00:42:35as to the reason why Iapetus is so starkly black and white.
00:42:39One of the puzzles going all the way back to Voyager is,
00:42:44is that dark material coming from inside Iapetus?
00:42:48Maybe some kind of volcanic eruption?
00:42:50Or is it coming from outside?
00:42:52And Cassini solved that puzzle.
00:42:54Turns out that there's a captured moon, Phoebe,
00:42:57in the outer part of the Saturn system.
00:43:00Dust from Phoebe comes in and gets swept up onto one side of Iapetus,
00:43:06coating that side in almost a charcoal black material.
00:43:11This black material absorbs heat from the sun,
00:43:15turning the moon's water ice into a vapor that accumulates like snow,
00:43:20falling on the trailing side of Iapetus.
00:43:24The result is the moon's distinct yin and yang veneer.
00:43:29Phoebe, the moon responsible for Iapetus dark material,
00:43:41resides on the outskirts of the Saturnian system.
00:43:48This is a frozen artifact from the time when the solar system was forming.
00:43:53Its battered surface speaks of a violent past.
00:43:56Everywhere there are ancient craters and landslides.
00:44:01Phoebe was the first Saturnian moon Cassini saw up close,
00:44:07and it proved to be a harbinger of the bounty to come.
00:44:11For at the time of Cassini's launch,
00:44:14there were just 18 confirmed Saturnian moons.
00:44:17Now there are 82.
00:44:21These moons are as diverse in shape, size, and composition as they are numerous.
00:44:28Battered Mimas, with its massive crater,
00:44:32resembles the Death Star from Star Wars.
00:44:35Hyperion resembles a sponge.
00:44:39Its interior is full of voids,
00:44:41so much so that it's thought of more as a rubble pile than a solid body.
00:44:46Atlas could be mistaken for a UFO,
00:44:50Prometheus a potato,
00:44:53and Pan a ravioli.
00:44:58These and other moons are part of Saturn's intricate system that influences the rings,
00:45:05the magnetosphere, and even the planet.
00:45:12And while best known for its rings,
00:45:15Saturn is deserving of its own attention.
00:45:18It is the second largest planet in the solar system.
00:45:23In volume, Saturn could hold more than 700 Earths.
00:45:28Composed mostly of helium and hydrogen gases,
00:45:37the planet has no solid surface,
00:45:40although deep within there is thought to be a dense core of metals.
00:45:44Despite its size, Saturn is astonishingly light,
00:45:51less dense than water.
00:45:53If it could be placed in an imaginary giant bathtub,
00:45:58Saturn would float.
00:46:00The planet's spin rate is also impressive.
00:46:05A Saturn day is only ten and a half hours long.
00:46:08This rapid rotation causes the planet to bulge out at the equator
00:46:13and flatten at the poles.
00:46:15Saturn's butterscotch exterior appears bland and calm.
00:46:22But this appearance is deceiving.
00:46:25Beneath the cloud tops is a churning cauldron of lightning
00:46:29and wind speeds that can reach over a thousand miles an hour.
00:46:33And about every 30 Earth years,
00:46:36Saturn experiences a megastorm.
00:46:38Cassini had the good timing to witness one.
00:46:45This raging storm would grow to encircle the entire planet.
00:46:51Even more amazing is what can be seen at Saturn's poles.
00:46:56Saturn has something unique in the solar system.
00:46:59It has a hexagon circling the North Pole.
00:47:03It's a six-sided jet stream.
00:47:09You can almost imagine horses on a racetrack racing around the hexagon.
00:47:16We don't know why it keeps its six-sided shape.
00:47:19It's some kind of a wave pattern that goes around Saturn,
00:47:23but it's very stable.
00:47:24It's been there for decades.
00:47:26It's about two Earth diameters across.
00:47:29At the very center, right at the North Pole,
00:47:33there's a giant hurricane.
00:47:35It's about half the size of the continental United States,
00:47:39with wind speeds about four times a typical hurricane-force wind.
00:47:47A second monster storm was discovered at Saturn's South Pole.
00:47:53It is also ringed with towering clouds but lacks a hexagon.
00:47:57And while this vortex looks like a hurricane,
00:48:00it doesn't behave like one.
00:48:04These are just some of the wonders of Saturn witnessed by Cassini.
00:48:08But still to come is an entirely different way to explore the planet,
00:48:13as the spacecraft nears its end.
00:48:16By 2017, Cassini had circled Saturn more than 250 times,
00:48:35and the mission's achievements had earned the praise of many,
00:48:39including the first human ever to set foot on another celestial body.
00:48:45Hi, I'm Neil Armstrong.
00:48:47We're here at the Cincinnati Observatory.
00:48:50Armstrong recorded this message to the Cassini team
00:48:53four years before his passing.
00:48:56It has been said, science is about what is,
00:49:00and engineering is about what can be.
00:49:05The Cassini-Huygens program has demonstrated the best of both.
00:49:10And you are the people who made it the enormous success that it has been and is.
00:49:17Some of you are in science of what is,
00:49:22unraveling the secrets of the Saturnian system.
00:49:26Someone's had a full-time job just counting moons.
00:49:30The number of your new discoveries is nothing short of amazing.
00:49:34Some of you were in the what can be category.
00:49:39You were involved in the design of the spacecraft and the trajectories,
00:49:42system design and operation, instrumentation,
00:49:47how to make the measurements, programming the computers.
00:49:51We all give you our very best wishes to continue your outstanding performance.
00:49:59Congratulations to each and every one of you.
00:50:07Cassini's original lifetime warranty was for four years at Saturn.
00:50:11The mission more than doubled that guarantee.
00:50:15In 2017, 20 years after its launch,
00:50:19the spacecraft was still performing beyond expectations.
00:50:24It's like the spacecraft just now broke in.
00:50:27Everything's working just perfectly.
00:50:30Yet Cassini's days are now numbered.
00:50:33It is running out of fuel.
00:50:35And before that happens, the spacecraft has to be set on a course
00:50:39that will ensure it will not crash into one of Saturn's moons that might harbor life.
00:50:48Given that Enceladus now appears to have all the ingredients that could harbor life,
00:50:55we have new rules.
00:50:58And frankly, we have a very nice home for microbes.
00:51:01It's room temperature inside the spacecraft.
00:51:02A hardy microbe could easily have hitched a ride along.
00:51:06We went through a lot of studies on disposal options for the spacecraft.
00:51:10Some of them were to take it into a very long loopy orbits of Saturn,
00:51:15where it would be stable for thousands of years.
00:51:17But the scientific benefit wasn't there.
00:51:20We also had options to go back to Jupiter, go out to Uranus, go to the Trojan asteroids.
00:51:24We could have exercised a lot of those options, but none of them had the strength and appeal of a scientific mission at Saturn.
00:51:32We were built for Saturn.
00:51:34Saturn was absolutely just bristling with things we hadn't yet explored.
00:51:38Once we chose to stay, we had to figure out how to dispose of the spacecraft cleanly.
00:51:44It's decided to end the mission by plunging Cassini into Saturn,
00:51:50but not before attempting to dive 22 times between the planet and the rings,
00:51:56a place no spacecraft has ever been.
00:52:13This is where Cassini is right now in its orbit of Saturn, below the ring plane, which goes out here.
00:52:26We'll come over the top of the rings again in a few days.
00:52:30We do this every seven and a half days.
00:52:33On April 22nd, the spacecraft will fly fairly close to Saturn's big moon, Titan.
00:52:39And Titan has enough gravitation that we can use it to trade orbital momentum between Titan going around Saturn
00:52:48and the spacecraft going around Saturn.
00:52:51And with that trade-off, a marvelous thing happens.
00:52:55The orbit of the spacecraft jumps inward towards Saturn so that the next close flyby of Saturn
00:53:02will be in between the rings and Saturn's atmosphere.
00:53:06Is that dangerous?
00:53:10We don't really know, but who knows?
00:53:13We might run into some big ring particles in there that we can't see in our observations.
00:53:19If that happens, oh well, it's been a good mission.
00:53:23If it doesn't clobber the spacecraft right away, then we'll have 22 more flights through all the way out a million miles.
00:53:30It's a million-mile-high roller coaster.
00:53:33Picture yourself going click, click, click, click, click up a huge roller coaster.
00:53:37And then starting in, it's just falling.
00:53:40As we whip through the space between the rings and planet, we'll be going 120,000 kilometers per hour.
00:53:49The most important thing, I think, is the moment when Cassini's signal reaches the Earth.
00:54:06That means that the spacecraft has gone through, I don't know, maybe a thousand different commands.
00:54:11Turning the spacecraft, operating the cameras and spectrometers and dust detectors and magnetometer.
00:54:18They make their observation, the spacecraft keeps turning and twisting to point everything.
00:54:24And the moment the signal hits Earth, we know that all of that in the past day has been successful.
00:54:31And I think that's party time.
00:54:32But before there can be party time, there's the less glamorous work of creating those commands.
00:54:46And sometimes testing them in tucked away labs.
00:54:50I think we're good to go.
00:54:51Are we large?
00:54:53Well, this is another sea colonel.
00:54:56So after this meeting, I'm going to have to switch out this sea colonel.
00:54:59Oh, that's right.
00:55:00467. This is 444.
00:55:01Okay.
00:55:02And this won't run in real time because it's synced up to the real spacecraft.
00:55:05So we're just going to be sitting there so it's got a reminder of when the first plane.
00:55:10Right. So the first AACS command is at 10-52-38.
00:55:15Yeah, yeah. This is interesting.
00:55:17What we're setting up is we're practicing a main engine maneuver.
00:55:21We could need in the last few weeks of the mission to either come up out of the atmosphere or go down into the atmosphere.
00:55:28So actually, we're just simulating about a one meter per second main engine burn.
00:55:35So the engine's going to burn for how many seconds?
00:55:38I'm not sure, actually.
00:55:39Four or five seconds.
00:55:41Do you remember?
00:55:42Joni?
00:55:43Joni, how long does the burn last?
00:55:46One meter.
00:55:48Six.
00:55:49What the spacecraft does is the spacecraft always starts from Earth point and it does a roll and then it does a yaw and then you'll un-yaw and then unwind and come back to Earth point and then relay all the data back down to Earth.
00:56:05We'll be able, because we're in the integrated test lab, we'll be able to see all the data in real time.
00:56:09So we're actually going to call it out in real time since we're practicing it.
00:56:14What does, uh, SWAMBO?
00:56:18It stands for she who always must be obeyed.
00:56:23It should take about 29 minutes.
00:56:26So here it is.
00:56:27Wine's yaw turn.
00:56:28And they're calling something out right now.
00:56:29Systems?
00:56:30Systems.
00:56:31Systems.
00:56:32Systems.
00:56:33What?
00:56:34The wine roll turn is complete.
00:56:35The reaction wheels have powered off.
00:56:36Oh, there it is.
00:56:37Oh, here we go.
00:56:38Hey, attitude control.
00:56:39You weren't listening?
00:56:40I wasn't listening.
00:56:41They said it.
00:56:42Tina called it out.
00:56:57Tina, I can't hear you.
00:56:58I'm sorry.
00:57:00You and Masashi, you're going to have to speak up.
00:57:02You're going to have to develop your Julie voice.
00:57:04Okay.
00:57:06you're going to have to develop your julie voice she she was literally just saying the words oh
00:57:12i have to announce when you said call out the burn status
00:57:22it is now more than a month later all of the testing of commands is over
00:57:28and on this evening team members and their families and friends have gathered to see if
00:57:33cassini will survive its first plunge between the rings and saturn
00:57:39the event has been given a name gateway to the grand finale well i just want to welcome everyone
00:57:46to our gateway to cassini's grand finale and this is a cassini family event and i'm so happy to see
00:57:54so many people here to share and what's about to happen tonight in 1990 linda spilker stood on this
00:58:02same stage speaking of saturn's rings saturn's rings are more transitory elements of this now three
00:58:08decades later she is cassini's project scientist and this evening's master of ceremonies so at midnight
00:58:16tonight will be the first time cassini turns back to the earth sends a signal and lets us know that
00:58:23it successfully navigated through this gap where it's flown for the very very first time so we we
00:58:30have a lot in store it'll be very exciting while awaiting news at midnight updates are given on
00:58:36cassini's latest science discoveries and a time-honored jpl ritual is acknowledged now i'm not particularly
00:58:45superstitious but you know there's a long-standing jpl tradition so last night i went out and i decided we
00:58:54needed to have some lucky peanuts just in case and i thought about it some more and i thought maybe we
00:59:03need two jars of lucky peanuts and with that i'd like to introduce the cassini virtual singers the virtual
00:59:14singers really take the heart and the soul of cassini and capture it with music so tonight live from
00:59:24jpl in pasadena california just back from their multi-world tour we now have the cassini virtual singers
00:59:38spirit
00:59:45you
00:59:48yeah
00:59:52oh
00:59:56Stand back, oh, stand back, stand back your data to me, to me.
01:00:26As the Cassini singers take their bows, light team members slip away to take up their positions
01:00:35on console in mission control.
01:00:37I read you five by also.
01:00:39Power, voice check on FSO chord.
01:00:41I read you five by five.
01:00:44I read you five by also.
01:00:47Check on FSO chord.
01:00:52I read you five by five.
01:00:55I read you five by also.
01:00:58Flight director and project manager, I'd like to announce at this time that all stations
01:01:02are ready to support.
01:01:04Copy it.
01:01:05Copy that, thank you.
01:01:07So you believe it, don't you just goidée?
01:01:19Just I know what you did?
01:01:20But when you know what you can't, it's really great.
01:01:23It could be fun.
01:01:25So I would you know time that it's just not my character.
01:01:28So, like that, see you next time those are the same.
01:01:34Okay, what we're looking at here is the mission support area, and they each have their various
01:01:49stations looking at different aspects of the spacecraft, and they just went through a check
01:01:55to make sure that everyone can hear everyone else in the MSA, and we also have sound into
01:02:01that room as well.
01:02:02So Eric, do you want to talk about what we're seeing on the screen over here?
01:02:05Yeah, so on the left, that is the signal that Deep Space Network is currently detecting,
01:02:11which is nothing.
01:02:12It's just a flat noise signal right now.
01:02:15But what we're all going to be looking for here is for a spike to pop up out of that noise,
01:02:21and when we see that spike, it means that we're receiving a signal from Cassini.
01:02:28We have X-Bank carrier signal detection in the open loop receiver.
01:02:32That's a nice booming signal.
01:02:41That's a nice booming signal.
01:02:53So the carrier signal is there.
01:02:56We'll have to wait a few more minutes until we'll see if there's actual data flowing.
01:03:00But this is a great sign.
01:03:05Receiving back Cassini's carrier tone means the spacecraft has survived the first dive.
01:03:11The signal just came booming through right on time.
01:03:15Couldn't have been better.
01:03:18Along with feelings of relief is the hope that science data will soon begin to flow.
01:03:25But now comes a moment of confusion.
01:03:28How to best listen for Cassini's signal?
01:03:31Asco Systems, Cassini Ace.
01:03:34The station is currently looking for the X-Ban one-way carrier signal.
01:03:39And they're also going to attempt to lock up to the 1896, so stand by one.
01:03:42I'll let you know if they get it.
01:03:46Ace, this is flight director.
01:03:47Don't have them lock up on the 1896.
01:03:51Okay.
01:03:52You just wanted to look for a carrier?
01:03:53And Asco Systems, Cassini Ace, the station has locked up to the X-Ban one-way signal at
01:04:00NEG 140 dB, which is expected for the 1896, right?
01:04:03No.
01:04:04Copy.
01:04:05No.
01:04:06It's okay.
01:04:07Asco Systems, this is Nav.
01:04:11Nav, go ahead.
01:04:13We're seeing a one-way Doppler signature.
01:04:16Copy.
01:04:17The moment of uncertainty ends as quickly as it began.
01:04:23And Cassini begins transmitting its science data sooner than expected.
01:04:31Flight director on that.
01:04:34Well, we're waiting for 12.05, but it looks like we're early.
01:04:39Copy.
01:04:48Oh, my God.
01:05:00Well, if there's any more questions, I'd be happy to take questions.
01:05:03That's—this is the big moment that we waited for.
01:05:06And it's here, and it's every bit as good as we had hoped.
01:05:11We're okay for 22 weeks.
01:05:14We're okay now.
01:05:19The spacecraft went through the rain plane just clean as can be.
01:05:23There are no indications of fault protection.
01:05:26Telemetry data playback is exactly where it's supposed to be.
01:05:29We can all go home.
01:05:30We don't have to spend all night fixing everything up.
01:05:32The spacecraft's in perfect shape.
01:05:43System lead, this is ASCS.
01:05:46ASCS, go ahead.
01:05:48The downlink roll has started.
01:05:50At this time, we would like to report that all the initial conditions checked out, initial
01:05:55attitude and wheel speeds look good.
01:05:58All instruments are on.
01:06:00The star tracker is tracking five stars, so that looks good.
01:06:03Both sun sensors A and B are both on, so they match each other's telemetry at this time.
01:06:11We're waiting for the roll to give us a full quadrant checkout for the rest of the path.
01:06:17Other than that, ASCS looks great.
01:06:20Copy.
01:06:21Flight director and project manager, this is systems lead.
01:06:25All subsystems have reported in, including the SIP lead at this time, and everything is
01:06:29nominal.
01:06:30Congratulations, everyone.
01:06:31Copy.
01:06:32Copy.
01:06:33Copy.
01:06:34Copy.
01:06:35Copy.
01:06:37Copy.
01:06:38Copy.
01:06:39Copy.
01:06:40Copy.
01:06:41Copy.
01:06:42Copy.
01:06:43Copy.
01:06:44Copy.
01:06:45Copy.
01:06:46Copy.
01:06:47Copy.
01:06:48Copy.
01:06:49Copy.
01:06:50Copy.
01:06:51Copy.
01:06:52Copy.
01:06:53Copy.
01:06:54Copy.
01:06:55Copy.
01:06:56Copy.
01:06:57Copy.
01:06:58Copy.
01:06:59Copy.
01:07:00data.
01:07:01Copy.
01:07:02Copy.
01:07:03Okay.
01:07:04Copy.
01:07:05Copy.
01:07:06Google.
01:07:07Hi.
01:07:08Hello, everyone.
01:07:09I'm Ge'yi Hill, and welcome to NASA's Jet Propulsion Laboratory.
01:07:10reached the end of its remarkable journey of exploration.
01:07:14Today the spacecraft made its final approach to the giant planet
01:07:18and plunged into the Saturn's upper atmosphere,
01:07:22ending this extraordinary mission.
01:07:25But due to the vast distance between Earth and the universe...
01:07:27The Cassini mission has actually not ended.
01:07:31Not yet.
01:07:32The grand finale event is still a week away.
01:07:36This is a rehearsal.
01:07:38The sun isn't up yet, and more than 1,500 Cassini scientists, engineers, alumni,
01:07:45their friends and family have gathered in Mission Control here,
01:07:49Von Karman Auditorium at JPL, Beckman Auditorium at Cal...
01:07:53What's true for engineers is also true for JPL's public communications team.
01:07:59A little pre-planning to work out the kinks can be worth its weight in gold.
01:08:03Australia, it's 4 a.m. here in California.
01:08:07The loss of signal really happened at about 3.30 Pacific time, a half hour ago.
01:08:13Why is the team here?
01:08:15We thought it'd be over.
01:08:17We will be checking back with you in just a couple more minutes.
01:08:21There is a huge crowd at Beckman Auditorium at Caltech right now.
01:08:26Cassini science team member Morgan Cable is there.
01:08:29Morgan, what is it like out there?
01:08:31Hi, Gay. This is Morgan here at Caltech, and the atmosphere is electric.
01:08:41I believe we're going to a bumper.
01:08:44And I'm one of those hoping that Cassini will hang in there and fight for the very last seconds of data.
01:08:51What's going on?
01:08:53Well, we've just got the word that Cassini has given us its last bit of data.
01:09:00The room is celebrating.
01:09:03Lots of hugs going on, a few tears.
01:09:06With me now is NASA Director of Planetary Science, Jim Green.
01:09:10Jim, thanks for joining us.
01:09:12You know, Gay, this really has been a historic mission.
01:09:14Before we do that, let's take a moment to chat with JPL Director Mike Watkins.
01:09:19What's your feeling about the success of the Cassini mission?
01:09:22You know, I could not be more proud about the role that we've had in this mission.
01:09:26With me now is Alvaro Jimenez, the ESA Director, and the Director of Science, Roberto,
01:09:34ESA Director of Science, Roberto Batistón? Batistón! Batistón!
01:09:42But all kidding aside, the planning paid off.
01:09:48For the elaborate multimedia and interactive coverage of Cassini's grand finale would be watched by
01:09:54millions. And the Emmy goes to NASA JPL Cassini's grand finale.
01:10:03And earn JPL its first ever Emmy.
01:10:06I got to thank the stars that made a bunch of geeky rocket scientists,
01:10:16rocket engineers and scientists, Indus rock stars.
01:10:19Here's the Huygens image of the gullies.
01:10:33Less than a week remains before Cassini's end.
01:10:37And team members from around the world are arriving to take part in the grand finale.
01:10:42And yet the site has...
01:10:44This is the final meeting of the Science Radar Group.
01:10:47So we've actually been at this for 40 years.
01:10:50This is an image from 1976. It's one of Bruce Murray's purple pigeon projects.
01:10:55And here's what became the Huygens probe, beaming the data to Cassini, which is flying by.
01:11:01As they meet, a billion miles away, Cassini is flying by Titan for the last time.
01:11:13Right now, Cassini is flying close to Titan, 74,000 miles away.
01:11:19And Titan's gravity has given Cassini its final push, its goodbye kiss.
01:11:25And its fate is sealed.
01:11:28And toast to great spacecraft, a wonderful mission, and our final pass by Titan.
01:11:35I worked on the Cassini mission for over 30 years.
01:11:38And that's the time it takes Saturn to circle the sun a single time.
01:11:43And when you work on a mission for that long of a time, and when you work for people,
01:11:47many of whom stayed and were there as long as I was, you really start to feel like family.
01:11:53You get to know each other, you take vacations together, you attend meetings together.
01:11:59You see your families grow up together.
01:12:01And then when the mission ends, it's hard because you know you'll keep in touch with this family,
01:12:06these people who feel like friends.
01:12:08And yet you also know you'll go your separate ways.
01:12:11So for the people who have been with the team from the beginning,
01:12:14thank you and I hope you found this.
01:12:15You are now 30 years wiser and smarter, and this has been a great experience.
01:12:20But for the people who joined later, hopefully you found that also a great stepping stone and
01:12:25great experience for you guys to lead the future of planetary exploration.
01:12:29So thank you again.
01:12:30Cheers!
01:12:31The next day, Cassini engineers gather for their last in-flight operations meeting.
01:12:4045502 is when we predict to hit 100% duty cycle, and AACS predicts loss of signal 12 seconds after that.
01:12:50Navigation, Dwayne.
01:12:52As of yesterday, at about 1.30 in the afternoon, we had our last Titan 5i, and we're on our way into Saturn now.
01:13:03DSN, Mike.
01:13:04So we had seven passes last week, 14 command files, including the last set of built,
01:13:11so we have no more commanding for real time.
01:13:13S101, Jan.
01:13:15Okay, the spacecraft's basically nominal. We have no new ISAs, no other errors. And then,
01:13:21basically, we've got the end of the sequence. We're just clocking out.
01:13:25Here we are, knowing that this is the end is very sad. But knowing in a mission like Cassini,
01:13:32where we had an ending date, we had a sequence of events to follow, gave us some purpose.
01:13:37All the teams stepped up. I'm very grateful for all your support, and just want to say thank you.
01:13:43Does anyone else have anything?
01:13:45Uh, yeah.
01:13:47Just because everyone else has piled on with the thank yous, you, here and in the room,
01:13:52and out on the phone, have rocked the world. And this is our last meeting with a spacecraft,
01:13:57but it has just been an incredible ride. I am very, very proud to have been associated with all of you.
01:14:03And as an incentive for next meeting, when we don't have a spacecraft, we will bring donuts.
01:14:09Thanks, everyone.
01:14:13I know you're already close.
01:14:25There's two hours.
01:14:26Two hours.
01:14:26Two hours.
01:14:27Two hours to come.
01:14:28Yep.
01:14:29It is now 2.55 in the morning in California. We've got about two hours to go until the end.
01:14:36Science data on the recorders is done. We're currently in our real-time plunge configuration.
01:14:44So everything now is essentially real-time data from the instruments as we go into the planet.
01:14:49The FFTs will begin to fade and decrease, and then at just one point, they'll just disappear entirely.
01:14:56And that'll be the end. That'll be the end.
01:15:10It's really hard to end the mission this way. This one's been my companion, constant companion,
01:15:22for 22 years.
01:15:23Okay.
01:15:25My job has always been to take care of the spacecraft. Everything's working just perfectly. I mean,
01:15:32you have to recognize the fact that we're out of propellants, but I have no idea how I'm going to feel.
01:15:38Look, this is my screen up here. So this screen here is the last 10 minutes of the one up at the top.
01:15:50The one at the top is kind of the big picture. And this one has atmosphere model. This is also the
01:15:58last 10 minutes, but this one does not have atmosphere model. So what we're hoping to see
01:16:03when we get to the very end and get into the atmosphere is this one's going to start
01:16:08being different from this one. Right now, they look very similar. Once this one starts changing
01:16:14from this one, then we know that we're in the atmosphere and we're experiencing drag on the spacecraft.
01:16:20About a minute before loss of signal, the other spot we've got over into the attitude control system,
01:16:26those charts on the right of that screen are showing thruster activity, and we're going to watch
01:16:30those just go right up the up the wall, so to speak. And again, for about a minute. I mean,
01:16:35everything happens so fast right now. Okay. So what we're seeing is each of these little places
01:16:42where the curve turns around is where the thrusters are firing. We're trying to control the orientation
01:16:46of the spacecraft. And every time we see a little change of direction, that's a thruster pulse. And
01:16:51those pulses are getting more and more frequent. And the reason for that is we're getting closer to
01:16:55Saturn and its gravity gradient is starting to rotate the spacecraft around. What's going to happen is
01:17:01eventually, instead of bouncing slowly along the edge, it's just going to be sitting right on the edge,
01:17:05firing the thrusters continuously, all the way up to the point where the thrusters are on fully,
01:17:10and it can no longer maintain that attitude. And then it'll just drift outside of our thresholds,
01:17:16and then we'll be tumbling. That will be the end of it.
01:17:18When do we want to tear up the ceremonial anomaly plan?
01:17:39If you think of Cassini as a symphony, this is the final, final movement. There's so many emotions. I
01:17:45mean, it's such a great, sweet ride it's been. It's been a triumph. We are a village. It has been a
01:17:52phenomenal teamwork. We finish each other's sentences. We tie each other's shoes. It is
01:17:57absolutely going to be something that I will never be able to recreate, and I will miss it greatly.
01:18:06Among those arriving is Mike Watkins.
01:18:09Whatkins is one year into leading JPL, the fourth JPL director Cassini has seen.
01:18:28Hello, everyone. I'm Gay Yee Hill, and welcome to NASA's Jet Propulsion Laboratory.
01:18:33After two decades in space, the Cassini spacecraft has reached the end of its journey on Saturn.
01:18:40The spacecraft made its final approach to the giant planet.
01:18:43Meanwhile, it is 4 a.m. here in California. The sun is not up yet, and more than 1,500 Cassini
01:18:52scientists, engineers, alumni, friends, and family have gathered for this moment. How does it feel,
01:18:58Todd, to be here? Hi, Gay. Well, it's great to be back. As you and I sat there in
01:19:022004, we never dreamt we'd be here in 2017, still talking about Cassini and collecting science data.
01:19:10So I'm just thrilled to be here, even having aged some years since SOI.
01:19:16Flight Director, Systems Lead. Go ahead.
01:19:18All subsystems are nominal. We are go for final launch. Copy.
01:19:22The spacecraft has just crossed 40 degrees north latitude. Copy. Thank you.
01:19:34The trajectory is the very latest trajectory that we've reconstructed with the latest data that we
01:19:39could get. So that little dot here, that's Cassini. So it's pretty accurate. And yeah, it's cool.
01:19:51Systems Lead. Mission Planning. There you go. Go ahead. Mission Planning.
01:20:02Spacecraft has just crossed 30 degrees north latitude. Altitude is 6,000 miles. Copy. Thank you.
01:20:10Miles.
01:20:10Miles. Yeah, it's fun to calling out miles. That's weird. Yeah.
01:20:18We usually don't use them. We never use them. Yeah.
01:20:22Well, we are a little over 10 minutes away from the loss of signal. So we will be focusing our
01:20:28attention to the control room very soon now. But before we do, let's take a moment to chat with JPL
01:20:34Director Mike Watkins. So Mike, how are you feeling? Well, first, good morning.
01:20:41Yes. Very early morning. We always tend to do these events somehow at three in the morning or five
01:20:44in the morning. Why did they do that? But you know, it's kind of a bittersweet
01:20:49event for all of us, I think. For me personally, it's more sweet than bitter because Cassini's been
01:20:54such a fantastic mission. But I think, you know, one of the important things about these events is to
01:20:58celebrate the incredible hard work, the decades of hard work of the team that designed, built,
01:21:04and operated Cassini. And that's really, right, the heart of the spacecraft is really the people
01:21:08that worked on it and the people that have been operating it. And this is a great time to celebrate
01:21:12those, those, that level of dedication, that devotion, you know, to work on something for 10, 20,
01:21:1730 years that, that's, that's sort of unparalleled in, in human history.
01:21:21We're still waiting for a transition to higher rate mode, but it looks like we're going to start
01:21:33accumulating thruster on time, um, at a, at a higher rate now. And, um, our attitude control error is,
01:21:39um, is starting to, to be more active. Copy. And, uh, we are in the atmosphere. Copy, thank you.
01:21:51All right.
01:21:57Oh yeah, there.
01:22:01That's good.
01:22:07Yeah.
01:22:21We have lots of signal that X-ray band and X-ray band.
01:22:51Project Manager, Flight Director.
01:23:16Go ahead.
01:23:18Okay, we call loss of signal 115546 for the S-band, so that would be the end of the spacecraft.
01:23:34Project Manager on FSO Coord, I hope you're all as deeply proud of this amazing accomplishment.
01:23:43Congratulations to you all.
01:23:45This has been an incredible mission, an incredible spacecraft, and you're all an incredible team.
01:23:50I'm going to call this the end of mission.
01:23:54Project Manager off the net.
01:23:57I hope you can do it.
01:24:02One more.
01:24:09Thank you very much.
01:24:39My feeling was I want to hug somebody and share saying goodbye, and that was hard, it
01:24:53was hard to say goodbye.
01:24:54And 7-4 if you're listening, project manager, program manager has confirmed end of mission
01:25:00at 1-1-5-5-4-6.
01:25:02This concludes Cassini's 13-year exploration of the Saturn system.
01:25:09The looks that you see on people's faces, we're not acting.
01:25:13We felt that.
01:25:14You're looking at raw emotion at that point.
01:25:16I thought I was going to be okay, and I wasn't.
01:25:18We did it, and it worked, but it's over.
01:25:21Now what?
01:25:22We're doing this long time.
01:25:23Yeah.
01:25:24Let's do another one.
01:25:25Yeah, let's do another one.
01:25:32Yeah, let's wait.
01:25:34Yeah, let's do another one.
01:25:39What is that?
01:25:41Yeah.
01:25:42Yeah, yeah.
01:25:44Yeah.
01:25:45Yeah.
01:25:50Yeah.
01:25:51Yeah.
01:25:52Yeah.
01:25:53Yeah.
01:25:55Yeah.
01:25:56Yeah.
01:25:58Yeah.
01:25:59Yeah.
01:26:00Transcription by CastingWords
01:26:30Transcription by CastingWords
01:27:00Transcription by CastingWords
01:27:30Transcription by CastingWords
01:28:00Transcription by CastingWords
01:28:30Transcription by CastingWords
01:29:00Transcription by CastingWords
01:29:30Transcription by CastingWords
Be the first to comment