What Did The Cassini Probe Teach Us About Saturn? | Naked Science | Spark

Saturn one of the most mysterious planets in our solar system now the Cassini hen's mission is exploring this enigmatic world and its moons for the first time it allows scientists to see what lies below Saturn's upper atmosphere and investigate the origin of its incredible Rings a probe touches down on the largest moon Titan to search for a world like our own and the possibility of life [Music] 5 4 3 2 1 of the cini spacecraft 4:43 a.m. October 15th 1997 an 1100 t Titan 4B rocket launches from Cape canaval it carries with it Cassini haens its destination lies almost 900 Million Miles Away at the awe inspiring planet [Music] Saturn a huge gas giant orbited by at least 60 moons Saturn is the second largest planet in the solar system over 750 times more massive than Earth it's a gassy world without solid surface the last mission to this mysterious planet launched over a quarter of a century ago the Voyager spacecraft sent back these images showing a planet shrouded in thick banded cloud onboard infrared cameras spot what looks like storm activity beneath the haze something big is brewing on Saturn the problem with voyager missions is that they were flyby missions they were onetime snapshot Voyager can't stop to investigate its flight plan is fixed scientist can only gather limited data Voyager 1 also skims the atmosphere of Saturn's largest moon Titan scientists are shocked at what it Finds Its instruments detect organic compounds in the atmosphere these are similar to the compounds that provided the raw material for life on Earth 4 billion years ago in a way Titan is a glimpse back in time to processes that may have been occurring on the early Earth that may have led to life but once again Voyager 1 can't stop to investigate it hurdles off at 39,000 mph into the cold outer reaches of the solar system the Voyager Mission makes tantalizing discoveries leaving scientists with more questions than answers they are determined to return to the mysterious moon and take a closer look we want to understand our own Origins we want to understand why the Earth came to be the way it is and how life came to develop here scientists believe by unlocking some of the secrets within Saturn and its moons we could learn how our own world developed and how life began Cassini is one of the most scientifically Advan Advanced spacecraft ever launched it will explore Saturn's atmosphere using an array of high-tech cameras and sensors Cassini carries with it a probe called haggens this will deploy to Titan Saturn's largest moon it will plunge through the thick atmosphere and land on its surface but first Cassini must make the Long Hall through 2 billion miles of space the mission control team used the gravitational pull of our neighboring planets to slingshot the spacecraft around Venus Earth and Jupiter giving it enough momentum to reach Saturn after seven years of flight Saturn looms into view Cassini captures this stunning image of the gas giant but before it can get close enough to begin its detailed exploration Cassini must pass through the Rings the Rings are chaotic and dangerous made up of billions of particles of ice and rock circling around the planet at high speed speed some chunks are as big as houses the only way through is to navigate a gap between the Rings Dr Jeff kozi is in mission control as Cassini approaches the Gap the Gap isn't something you would see with your eye so it wasn't exactly like there was a huge tight tolerance you know a narrow you know threading the needle kind of a thing tension builds as the high-risk maneuver begins Cassini fires its rocket engines to position itself and heads for The [Music] Gap its antenna points away from Earth communication is temporarily lost Dr Larry Esposito waits for the signal to return the sign that Cassini has made it through in one piece everyone was holding their breath waiting for the signal to come from the spacecraft to show that it had successfully passed through the ring plane several hours later they get the signal the doler has planed out [Applause] Cassini has made it through once that happened the silence ended broke into cheers Applause people hopped up shook each other's hands some people hugged each other was a great moment of success after Decades of planning for the first time a spacecraft has entered orbit around a planet in the outer solar system [Music] and for Dr Tony delgo it's in the perfect position to start exploring this gas giant the beauty of the Cassini mission is that for the first time we get to go into orbit around a planet like Saturn and for years observe it over and over again from different angles and by putting that together over this long period of time finally some of the secrets start to be revealed to us the first task is to explore What Lies Beneath Saturn's thick upper atmosphere Cassini Maneuvers towards the South Pole there its instruments reveal an unexpectedly familiar phenomenon a monster hurricane like Vortex this actual image clearly shows the storm and its scale this feature is more than 1,000 miles across so many times the size of a of a real hurricane on Earth and what you're seeing is a sequence of images showing the clouds rotating around the South Pole this is the first hurricane likee storm ever detected on any Planet other than earth like hurricanes on Earth it has an eye circled by a gigantic column of clouds but this one Towers 45 M high around it winds rage at 350 M an hour cassini's cameras zero in on the High Altitude clouds in the upper reaches of the eye wall temperatures here are minus 167° F the pictures capture what must be a flurry of ice crystals scientists are enthralled like Earth Saturn has storms with swirling clouds strong winds and even snow it definitely snows on Saturn in the upper reaches of the storm systems that we see I think we're pretty confident that there would be large ice crystals when you got down much deeper than we can see to in the images then we would expect actual liquid water rain to be falling out of the bases of those clouds on our planet hurricanes are fueled by the ocean and ultimately the sun Saturn is far too distant to draw the kind of solar power its monster storms need so what drives them when you get into a gas giant atmosphere like Saturn once you get a wind going you can maintain it for a long period of time without a solid surface underneath it to dissipate it very quickly but still slowly over time if you didn't somehow put energy into the system the winds would still dissipate now scientists investigate the theory that the energy for the storms comes from deep inside the [Music] planet it's a theory they've never been able to Pro [Music] improve but at a laboratory in France an extraordinary experiment is trying to verify its basic principles Cassini captures these images showing a monster storm on Saturn a gigantic hurricane 2/3 the diameter of Earth rages at the planet's South Pole winds encircle the central eye at over 350 [Music] mph scientists want to know what fuels these storms Saturn is too far from the Sun for them to be driven by solar energy the power source must lie elsewhere many scientists believe it comes from deep within the [Music] planet at the Coriolis laboratory in France astrophysicist Peter Reed searches for evidence to support the theory he is using an internal heat source to recreate Saturn's turbulent atmosphere the overall objective is is to try to come up with an understanding of uh what what processes actually drive the winds and organize them uh into into banded structures uh into these these these sets of alternating uh Eastward and Westward jet streams uh on on Saturn and and and the other gas giants inside this huge rotating tank is almost 40,000 Gall of fluid this this acts like Saturn's gases a heater sits in the base of the tank to simulate a heat Source deep inside Saturn I think that's an interesting thing this one piece will make 52 layers watch on mobile devices or the big screen all for free no subscription required [Music] suspended in the fluid are tiny light sensitive particles so these particles act uh basically like clouds in Saturn's atmosphere so they'll be carried around by the winds uh and this will help us to actually Trace out where the where the vortices and the Jets are actually actually occurring Reed wants to see if currents and vortices develop in the same way they do on Saturn's surface the tank spins to mimic the rotation of the planet the tiny particles start to spread out and [Music] interact slowly the particles begin to swirl and create Vo okay so we can see uh evidence of of a of a jet structure and then here we can see a very nice uh rotating structure which is basically an anticyclonic Vortex compare these to Saturn's twisting patterns of [Music] clouds the similarities are [Music] striking Reed's experiments suggest that a heat Source within s could fuel the Raging storms but what lies in its Center that could generate that much heat the gas giant is approximately 75% hydrogen and 25% helium with traces of water methane and ammonia scientists believe that like Earth Saturn has a hot core Earth's internal energy comes from radioactive materials in the core and residual heat from its formation but here on Saturn scientists think heat is generated by highly pressurized gases deep down in Saturn's atmosphere the pressure of the gas builds near the core the pressure is several million times higher than on Earth's surface it's so powerful that the hydrogen and helium gradually turn from gases into strange metallic liquids if you get deep enough then the hydrogen and helium become so dense that they don't behave like a gas anymore they behave more like an electrically conducting metal this liquid swirls around a rocky core that is roughly the size of Earth but just as oil and water can't mix the liquefied metallic element can't hold together the heavier helium separates and sinks through the hydrogen scientists believe this movement creates friction that generates heat Cassini is looking for evidence supporting this Theory by measuring the precise abundance of helium in the atmosphere it's already aass to vast amount of data there's so much that it will take years to analyze scientists hope to find out for certain how Saturn can give out three times more heat into space than it receives from the Sun Cassini is unveiling Saturn's turbulent activity in unprecedented detail now its main engines fire and Mission Control steer the spacecraft outward to explore one of the greatest mysteries in the solar system Saturn's chaotic Rings Saturn has the largest and most spectacular rings in the solar system the Voyager missions first revealed their awesome scale more than 25 years [Music] ago the Voyager spacecraft show that the Rings are chaotic they're made up of billions of chunks of ice and rock colliding into each other if you were to fly over the top of the Rings very close so you could actually see them you'd see something that would look a little bit like a flying Boulder Field small particles manging between a fraction inch in size and maybe a couple of yards across the turbulent Rings got scientists thinking the particles orbiting Saturn resembled the disc of gas and dust that encircled our young son 4.5 billion years ago the particles started clumping together growing larger and larger until after millions of years they eventually formed the planets in our solar system could the same process be occurring inside Saturn's rings is this a good analogy for how planets May grow Cassini sends back these stunning highly detailed images I was very uh very excited to see see these beautiful beautiful images we're going to learn a huge amount just from the first couple of images Cassini uses an UltraViolet Imaging spectrograph to map out the Ring's structure with remarkable Clarity the spectacular detail that we saw was just an eye opener and we stood amazed to see the structure that was in the Rings much more than I had personally expected as the particles pass in front of distant Stars the UV spectraph measures the amount of star light shining through areas that contain a lot of particles block staright and appear darker where there are fewer particles more light passes through scientists interpret the darker regions as temporary clumps of ring particles they are known as moonlets Cassini captures them on film for the first time they appear as bright lumps within the Rings these big boulders may very well be nothing but an agglomeration of the smaller ones and these agglomerations may come in go with time as they bump into each other they may just fall apart and collapse and then they may reform by their own gravity and stickiness on the surfaces scientists are fascinated by the images they think this process happened in the early solar system 4.5 billion years ago the planets Grew From microscopic specs to the size they are today the interaction between the the moonlets and the ring particles is exactly like the interactions between a planet and the dust that's collecting to make that planet grow Cassini spectacular images offer new insight into the processes behind the formation of our own world and the entire solar system but where did all the material that makes up the Rings come from in its infancy the solar system was a violent place comets and asteroids regularly collided with young planets creating massive explosions and leaving behind scars that we can still see today this image modeled from real data shows Saturn's Tiny Moon mimus this giant crater dents its surface a scar from a gigantic impact mimus was lucky it survived the impact but scientists think that Saturn could have lost one of its other moons completely shattered into billions of fragments imagine an object coming in that's the mass of a small planet or a big Comet coming in there's a huge amount of energy there it could actually rubel eyesee it pretty well Saturn's powerful gravity could have captured the fragments and over time compressed them into a flat plane around its equator these strange rings may be the result of the Solar System's most intense period of planetary bombardment they may also unlock the secrets of the Solar System's birth 4 and a half billion years ago cassini's next stop provides scientists with another opportunity to step back in time to a world like Earth before life evolved this is the mysterious moon Titan Cassini is crossed over two billion miles of space to reach Saturn and its moons it carries with it a secondary space probe called haggens designed to land on Titan one of Saturn's 60 moons Titan is massive it weighs almost twice as much as Earth's moon it's an object that's perplexed scientists for decades in 1980 Voyager 1 sends back these intriguing images of a world shrouded in a thick orange atmosphere analysis reveals that this is mostly made up of nitrogen just like Earth's the spacecraft also detects water and traces of organic compounds like ethane and carbon dioxide compounds that could provide the raw materials for Life Titan's atmosphere appears to be REM remarkably similar to that of early [Music] Earth now haggens returns to pick up where Voyager left off to search for signs of Life Dr Carolyn Porco was a young PhD student on the Voyager missions you can imagine that um for those of us who had been involved with the Voyager mission 24 years earlier that there was a tremendous amount of anticipation in returning to the Saturn system Cassini sophisticated cameras alone can't fully penetrate Titan's thick atmosphere what's on the surface beneath the thick Haze our first pictures of Titan were very mystifying in fact our images are painted on this globe and it's very difficult if you look in details to see exactly what you're looking at cassini's probe haggens is designed to solve this mystery the probe hits Titan's dense atmosphere at over 13,000 mes per hour at first its cameras only transmit these images of a thick yellow Haze but at around 30 m up Titan surface comes into Focus it's just very difficult to describe accurately what it was like to see the first images that they showed of the surface of Titan because it they were mindblowers these images show an extraordinary desert-like landscape with low Hills and rolling plains but Mission engineer Dr Ralph Loren worries where haens will touch down uh we had no idea what it was going to land on we didn't even know if it would survive Landing uh it could have landed in a a lake of liquid hydrocarbons it could have landed on a solid sheet of ice or or a a sand to the relief of all haens lands on level ground and survives it's the first probe to touch down on another world in the outer Sol solar system onboard cameras reveal an eerie alien landscape Loren rigged the probe with an instrument to analyze the composition of Titan's surface uh one thing it did is it had a an instrument called a penetrometer which was rammed into the ground and told us how hard the surface was it was it was the texture was like a damp sand or even a soft clay and uh there were indications that there might have been a pebble or a crust on top and it was even the the joke that the surface was made of creme brulee the penetrometer reveals haens has touched down on soft ground but not just any [Music] ground its camera shows smooth round rocks similar to those found in a riverbed there were a lot of rounded Pebbles around and the way you get rounded Pebbles is that they're tumbled in a stream and so this area which had River gullies uh must have been rained on sometime in the past and the the rain washed down tumbling these [Music] Pebbles hens discovers signs of liquid on the moon's surface so right away there was this unambiguous uh sign of a process that we knew how to interpret so this was tremendously exciting it said there had to be liquid something flowing on the surface of Titan but is the liquid water haan's thermometer registers the surface temperature as 290 below zero in This Bitter climate water would freeze as solid as rock but if water didn't carve this riverbed what did as Higgens continue to probe from the ground Cassini moves to the moon's Uncharted North Pole its radar penetrates the smoggy atmosphere to reveal dark patches these indicate something astounding Lakes liquid may still flow on Titan surface but what liquid can withstand freezing temperatures cassini's Visual and infrared mapping spectrometer picks up a dramatic cloud system it's enormous engulfing almost the entire North Pole scientists suspect these clouds could Supply the liquid that appears to fill Titan's Lakes Cassini homes in on the clouds and finds they are made of methane it seems that Titan surface has been carved not by water but by liquid methane we've uh counted up uh the volume of liquid in some of these lakes and it's hundreds of times the amount of all the liquefied natural gas all the oil on Earth the super cold temperatures on Titan allow methane to exist as a liquid any water on this moon is frozen solid surface conditions are not conducive to life but Titan's atmosphere is another story scientists focus in on the tiny particles suspended in Titan's atmosphere first discovered 25 years ago they are a cocktail of organic molecules the stuff of Life molecules like these existed on Earth 4 billion years ago if scientists can understand how they form on Titan they can figure out how they developed into life on Earth Cassini isolates the exact mix of molecules and transmits its findings back to Mission Control astrobiologist Dr Chris McKay has been trying to recreate Titan's atmosphere in the lab using the data from Voyager as soon as the Cassini results came in we scrambled to change our experiments to line them up with the new information it was like working on a problem for a decade and then finally seeing a glimpse of the answer in the back of the book and realizing aha this is the way to go McKay now tries to use this formula to turn simple organic molecules like methane and nitrogen into the building blocks of life in his lab he simulates Titan's pressure temperature and nitrogen Rich environment here is a tank of methane and nitrogen this is the starting mixture for Titan's atmosphere flows through the apparatus into our reaction chamber so now I'm going to turn on the the energy source and this flow of methane and nitrogen will experience the same kind of energy processes that are going on in Titan sepper atmosphere then McKay uses electricity to simulate the sun's ultraviolet radiation we have Titan in a jar after a few hours the simpler molecules turn into complex nitrogen-rich substances called tholin These labade tholin are almost exact copies of those found on Titan understanding how they form gives us valuable insight into the origin of life on Earth one overall question in studying Titan and comparing it to the early Earth is the question of how unusual is the sort of chemistry that led to life on Earth is it is it very rare and it happened on Earth because of very unusual circumstances or is it commonplace organic chemistry that we can expect on any world that's like Earth or even like Titan and if we find that there's a common theme the common way in which this kind of process goes maybe the steps that lead to life are common place and therefore life is Common Place the Cassini mission to Titan reveals how life could emerge on other worlds on the surface hen's batteries die out its Landing represents one of the great achievements in the history of space exploration haggens provided a spectacular view of Titan and returned over 750 images and over 3 hours of data Cassini abandons haens on Titan and heads for another Moon which scientists believe could be its greatest Conquest Enceladus Cassini continues exploring the Satan system in its sights the moon [Music] Enceladus covered in ice Enceladus is one of the brightest objects in the solar system cassini's cameras capture these detailed images of this dazzling Frozen world its ancient wrinkled surface is made up of fractured Plains craters and folded mountains but as it skims past cassini's magnetometer registers some kind of disturbance this is the actual recording the moon creates fluctuations in Saturn's immense magnetic field but [Music] how the magnetometer detects gas coming from the moon's surface experts suggest it must have some kind of partial atmosphere planetary scientist Professor Bob Brown thinks this is impossible they said hey um you know we're seeing evidence of a tenuous atmosphere around Enceladus and uh many of us responded with skepticism because an object like this can't have an atmosphere Enceladus is just 300 miles across it is too little gravity to hold on to an atmosphere for very long but things are about to get stranger the magnetometer group told us the atmosphere around inela seemed to be concentrated around the South Pole which is even weirder atmospheres don't do that they distribute themselves uniformly around an object the team is mystified what could create a strange localized atmosphere Cassini moves closer the spacecraft captures this stunning image giant geysers on the surface of the Moon appear to throw out huge plumes of vapor the unidentified gas blasts over 400 miles into space to see this image okay where we have two dozen a dozen to two dozen Jets narrow Jets just emerging from the South Pole was you know it was it's one of those things that a person who lives the kind of life I lead lives for okay it was just one of those discoveries that you know you're not going to make often in your lifetime Cassini spectrograph analyzes The Vapor of the Jets it contains water this discovery is completely unexpected could liquid water exist on this Frozen Moon Cassini is looking for liquid water on Enceladus it zeros in on an area of the Moon covered with cracks but one of the things that was absolutely stunning about this is that we want when we got into these areas where these cracks are they're clearly a lot warmer it may very well be that the temperatures there are as high as0 degrees C it may very well be that they're high enough that liquid water is literally very very close to the surface Cassini has found a hot spot an area warm enough to support water in its liquid form that was just you know mindblowing like what what could be possibly producing this it's one thing to find a body to be warm it's another thing to find that it's it's only warm in one location scientists are baffled what generates these pockets of heat enceladus's orbit is elliptical its distance from Saturn varies over time one theory is as it passes close to Saturn its crust flexes then as it moves away it relaxes friction at the fault lines generates heat perhaps enough heat to melt ice within the faults Enceladus flexes its body okay and so that can uh produce friction enough to melt ice to create liquid water the prospect of liquid water on one of Saturn's moons demands further investigation the first step is to determine the exact composition of the plan clons mission control fly Cassini just 30 m above the moon's wrinkled surface passing through the geyser's outer edge its instruments measure the composition the results are completely unexpected the plumes contain water vapor nitrogen and even simple organic molecules it doesn't take much of a jump at that point to make the association that if you have water you have heat and you have organic chemicals you have the conditions that might actually produce primitive life scientists now believe that Enceladus has conditions that can sustain life living organisms could survive around the warm faults that sit at its Southern pole the latest theories suggest that the faults in the terrain here May stretch down to a Subterranean sea this would be a dark World devoid of sunlight but life may still have emerged here on Earth primitive organisms thrive in similar hostile and extreme environments scientists speculate that the same could be true of Enceladus there's the possibility of having something akin to those hydrothermal vents that we see at the bottom of the ocean and we know they're living organisms there there's chemistry that goes on there that uh living organisms can utilize to live it's a tantalizing possibility if there are living things on Enceladus the implications would be profound what could be a more important scientific discovery than to find out life has evolved separately in some other place that changes the whole picture for human beings if we could demonstrate that the origin of Life Genesis had occurred twice independently then as far as I'm concerned the spell is broken we could safely infer life had occurred an astronomical number of times throughout the cosmos in its 13.7 billion year history so this is why it is such a pressing question for us Cassini shows us that life may be possible on alien worlds on April 15th 2008 more than 10 years after launch NASA announces that the mission will be extended for a further 2 years parts of its tour will be dedicated to the exploration of Enceladus and Titan perhaps it will make the biggest discovery of them all life on another world

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Keywords: Astronomical discoveries, Astronomical research, Cosmic exploration, Cosmic mysteries, Engineering, Exploration of Saturn, Outer space exploration, Science, Solar system exploration, Space education, Space expedition, Space exploration history, Space facts, Space journey, Space mission details, Space phenomena, Space research, Space travel details, Space travel technology, Spark, Voyager mission

Id: nU0iZnoLhBc

Length: 45min 46sec (2746 seconds)

Published: Fri Feb 23 2024