on September 15 2017 in an epochal sacrifice worthy of a god one of humanity's greatest feats of exploration finally came to an end in a glorious death spiral after executing 22 swan-like arks around the planet Saturn and making the first ever observations of the region within the planets rings a spacecraft turned its eye toward the.
Swirling storms below and plunged into the planets upper atmosphere igniting into a meteor and merging with the seeding clouds intended as the follow-up to the hamstrung Galileo mission the Cassini mission to Saturn which so far surpasses that for 13 years it effectively became an outpost for our civilization making the most distant of the ancient planets.
As familiar to us as our own and providing images comparable to the greatest art Cassini was launched in 1997 when Galileo was just completing its primary mission around Jupiter arriving in Saturnian orbit in 2004 it proceeded to image the planets dizzying gallery of moons rings and shrouded storms in unprecedented detail Cassini was not the longest of NASA's planetary.
Orbit missions indeed the Mars Odyssey orbiter has been circling its planet since 2001 but it was perhaps the most expanding revealing landscapes both utterly alien and shockingly familiar all never seen before and all forged primarily of water one of these water worlds in particular had seized the imagination of Cassini's crew before the probe had even been launched Cassini was.
Named after giovanni domenico cassini an italian astronomer who lived during the 17th and early 18th centuries a younger contemporary of galileo he would follow in the great man's footsteps not only by discovering four new moons of a distant planet but also by naming them after his patron in his case king louis xiv of france these louisiana stars or sedara louisia.
Would eventually be named Iapetus rhea tetiz and D&E he was also the first discovered that Saturn's ring was not a homogeneous structure but appeared divided by a wide gap now called the Cassini division somewhat ironically given that we now know that Saturn's rings are riddled with gaps and grooves we also know that the Cassini division is not one of them but is in fact a band.
Of dark material despite his name attaining the glory of a NASA mission in truth Cassini was something of an also-ran in the story of the exploration of Saturn while he may have enriched our understanding of the complexities of the Saturnian system he was not the one to first crack open the sixth planet and reveal its mysteries the namesake of the man who was was.
Tucked snugly into the spacecraft side awaiting its soft release and final descent into the frigid atmosphere of one of the strangest worlds in the solar system the Hardy little probe was named Huygens Quiggins region excuse me I think I may be able to help here oh hi Fred a mythic he's a friend from another channel this writes on my channel I talk about life on other planets alternate.
History and other interesting stuff yep love your illustrations by the way seriously guys check them out they're really cute but why do you think you can help me here well I am myself of Dutch origin and I heard you were struggling with the pronunciation there I guess Dutch pronunciation a stumbling block for even the best intention English speakers I'd certainly be grateful for.
Any advice awesome okay so the first tricky part is the diphthong you I in modern spelling or uy in archaic spelling it sounds like this the next stumble block is two letter G pronounced s which you may know in English from Scottish law although generally more recipe so heavens heavens yeah that will do I'm sorry the Dutch language is a bit special now I don't want to keep you.
From your fascinating video so please do carry on love your channel by the way dinner and looking forward to your next video so what Galileo Galilei II was to Jupiter Christian heavens was a Saturn the first appear at that indistinct star and begin to prize out its individual personality and augments in particular he was the first to identify that Saturn had a ring Hawkins was born in 1629 to.
One of the most distinguished families in the Netherland as befits a man of the Renaissance he was a mathematical and engineering prodigy by the age of 23 he was already manufacturing the most powerful telescopes of his time with up to forty three times magnification more than double that used by Galileo by the age of 27 he had invented and patented the pendulum clock.
Yes the same pendulum clock in your grandparents hallway which would remain the gold standard for precision timekeeping until the invention of the quartz oscillator in 1927 Hopkins was a Purdue's academic and writer as well the same year he patented his clock he published his first treatise a refutation of Descartes speculations on elastic collisions as a writer he aimed.
To popularize astronomy for the general public his musings on the possibility of extraterrestrial life call to mind those of Carl Sagan three hundred years later a man that he's of Copernicus's opinion that this earth of ours is a planet carried round and enlightened by the Sun cannot but sometimes have a fancy but it's not improbable that the rest of the planets have their dress in furniture.
Nay and their inhabitants too as well as this earth of ours unbook Galileo had shown that the Moon and Sun were not ethereal mystical objects but perishable terrestrial worlds just like our own if that were the case should they not also have life for all that it is for a series of discoveries made with his groundbreaking telescope in 1655 at the age of 26 for which Howkins is best.
Remembered in March of that year alongside the aforesaid ring discovery halcon's became the first person since Galileo to find a moon around another planet unlike Galileo he failed to find more than one and so simply referred to it as quote saturnine Luna or Saturn's moon even Cassini would neglect to name his own crop of moons it would not be until.
1847 a year after the discovery of the last planet Neptune that renowned astronomer John Herschel would establish the convention that Saturn's moons be named for the Titans the deposed family of Cronus the Greek Saturn the six smaller of Saturn's and known moons were named after specific Titans or type neces while Hawkins moon the largest was named simply Titan.
Evidence prior to the Voyageurs suggested that water was the prime material of the Saturnian system though water frozen to temperatures approaching absolute zero but what would these rocky snow balls actually be like dynamic active worlds like our own or inert undifferentiated lumps when the Voyager is at last reached Saturn in the early 1980s the retinue of snow white pearls.
They revealed not only show that the Saturn system was geologically alive but that ice like rock on earth is the material out of which these geological forces shaped and sculpted their surfaces into myriad landscapes at Saturn's distance from the Sun ice effectively petrifies adopting the properties of rock allowing you to display many of the features that on our.
World would be forged from granite or basalt the moons of Saturn were revealed to be riven by tectonic fractures like the rift valleys of our world broken by upwelling booms of magma composed of liquid water they should regions devoid of craters indicating that their surfaces have been covered over with fresh material from below the idea that cryovolcanism or volcanism in which.
Liquid water plays the role of lava was present in the Saturnian system was suspected prior to the voyagers arrival though frustratingly no evidence of active volcanism was observed it would finally be observed by Voyager 2 on Neptune's moon Triton in 1989 though Neptune's realm live so far from the sun's light that the eruptions were not of water but of nitrogen.
But there was one part of the Saturnian system the Voyager teen prioritize above all else so much that they sacrificed one of their probes to study it both voyagers visited Jupiter and Saturn but only Voyager two would go on to Uranus and Neptune upon reaching Saturn Voyager 1 was shunted off the mainline and redirected to its final stop Titan Titan is far and away the largest moon of.
Saturn one of two moons in the solar system larger than the planet Mercury the other is Jupiter's moon Ganymede but while Jupiter has its four giant moons and little else for the material in orbit around Jupiter excluding the Galileans what together comprise a not very large asteroid Saturn has one giant moon and a swarm of tiny worlds accompanying it but that one giant moon.
Is truly exceptional as I'm sure you've noticed from the images so far Titan is the only moon in the solar system with a substantial atmosphere how Titan a world with a surface gravity comparable to our own airless moon could have an atmosphere is still not fully understood though one reason is certainly its location a tightness distance from the Sun not only to the frigid temperatures.
Keep gases calm and sluggish but the solar wind the bane of the atmosphere of Mars is relatively weak lessening the effect of events such as coronal mass ejections the presence of an atmosphere around Titan was first observed by dutch american planetary astronomer Gerard Kuiper in 1944 when he detected methane in the moon spectrum and yes he was an American citizen by that point so that's.
Probably how he pronounced his name but the precise nature of that atmosphere was unknown some models predicted that methane would comprised 90% of the atmosphere and that its surface pressure would not exceed 20 millibars or about 2% of Earth's others suggested that nitrogen could form a substantial part of the atmosphere and that it could be up to 20.
Times thicker than Earth where not the case the greenhouse effect could warn the surface to a near earth-like 200k or minus 73 degrees Celsius surprisingly media depictions of Titan in the years prior to the arrival of the voyagers 10 to be rather conservative falling in line with the thin atmospheric model it was the scientists who were aiming for the truly exotic certain atmospheric.
Models for titan produced a surface temperature of 94 K or minus 179 degrees Celsius which happens to be very close to the triple point of methane the same gas found in Titan's atmosphere a substances triple point is that it which is capable of existing as either a solid liquid or gas earth's surface temperature happens to be very close to the triple point of water a fact not.
Coincidental with the development of life on Earth water flows across the surface as a liquid rises into the air as gas Balls's rain and then is frozen solid as ice this water cycle is the foundation for all life on land sustaining and nourishing both plants and animals to those excited astronomers it was immediately apparent that Titan may possess an alien frigid analogue of.
Earth's water cycle in which liquid methane falls from clouds and collects in lakes or seas but that was only one aspect that made Titan so enticing spectrography had already shown that methane interacting with sunlight had produced a number of complex organic molecules in the atmosphere such as acetylene or ethylene this may tighten a curious analogue to the early Earth.
Where similar basic carbon chemistry likely led to the origin of life these possibilities may tighten an irresistible prospect for the Voyager team so much that to reach it they condemned one of their craft to expulsion into the interstellar void but the team were already anticipating that the mission may be an anti-climax Pioneer 11 the dry run for the Voyager.
Missions had taken the first ever images of Titan I'll be aided a considerably lower resolution than Voyager 1 would and shown it to be a blank featureless disk and as Voyager 1 reached the end of its borrowed time mission it found that pioneers images had been if anything too optimistic Titan was a world hidden from the universe lost behind a shroud of impenetrable haze so.
Extensive was this haze that had actually led to Titans demotion prior to voyagers arrival astronomers had assumed that Titan was the largest moon in the solar system but it was forced to concede that position to Ganymede after Voyager showed that what they had initially taken from the surface was merely the top of titans opaque atmosphere which led it to appear about.
150 kilometres larger than it actually was Voyager 1 was able to confirm what pioneer had suggested Titan's atmosphere was indeed thick thicker than Earth's in fact at one point five atmospheres as predicted for a thick atmosphere nitrogen dominated at 98.4% with the notorious methane only making up 1.6 percent and hydrogen 0.2% this meant.
That Titan had the only dense nitrogen-rich atmosphere in the solar system other than our own but Voyager 1 did make one truly titillating discovery the most exotic models were right titan did indeed hover at the methane triple point but the visions of methane storms rising methane waves crashing on reefs of ice would have to wait until the arrival of a more capable craft needless.
To say when that craft arrived it was primed to well attack Titan not only did Cassini possess a radar mapping device specifically designed to peer beneath Titans clouds but it also carried with it a peculiar bit of cargo courtesy of the European Space Agency a small probe called POW ins in the most distant landing ever performed by a spacecraft how ins would descend to the.
Surface of Titan beaming what it saw from its first break through the haze to its final arrival on the moon's icy ground these probes revealed a world that shocked in its similarity to our own from its smooth River pebbles and craggy mountains covered in methane snow - it's dry riverbeds resembling nothing so much as arroyos from the American Southwest Titan appeared as a dark.
Photo- of earth a billion miles from the Sun and in January 2007 while passing over Titans North Pole Cassini's radar mapper confirmed what everyone had hoped the weird waters of Titan had indeed formed into lakes a suite of hydro carbon mirrors scattered across the Titanic Arctic the largest the wonderfully named kraken moiré has a volume comparable to that of the caspian.
Sea the largest freshwater lake on earth the lakes were clearly fed by tributaries and almost mirrors smooth though the occasional ripple has been detected but for those who dreamed of methane seas as deep as our own all hope was shattered Titan was a desert world a desert built of solid water but a desert nonetheless ironically it was too warm for liquid methane to permanently.
Collect in its lower latitudes which were dominated by huge fields of rolling dunes not of sand or even of ice but of solid hydrocarbons but those dry riverbeds seen by Hopkins had to have been filled at one time where they are relic from Titans distant past like the rivers of Mars but where they periodically filled with seasonal rain it's important to note here that seasons.
On Titan are on a scale unimaginable to any earthling Saturn's year is 30 earth years long so Titan seasonal regions might lie fallow for decades thankfully Cassini's 14 year 10 around Saturn amounted to fully half-ass attorney in year and so it was able to observe the seasonal transition as Titans northern hemisphere past from winter into spring as Saturn entered its.
Equinox in 2009 the Cassini team saw the equatorial region erupt in methane clouds during one such cloud event the Cassini team observed a dark patch on Titan surface appear to darken further indicating that had been moistened by falling rain the first ever direct evidence for extraterrestrial rainfall however models suggest that rain on.
Titan would be very different indeed to its equivalent on earth the lower gravity and thicker atmosphere mean that not only would rain fall more slowly but the droplets could grow much larger twice as large as raindrops on earth Titan is the only other world in the solar system on which rainbows might be observed that he'd probably need night-vision goggles to see them since.
Most of the sunlight penetrating the endless haze is infrared one pressing question is where the methane in Titan's atmosphere came from in the first place over time the Sun should have converted all the methane into more complex hydrocarbons so the methane must be replenished from somewhere the leading place of origin is within Titan itself cryovolcanism has yet to be observed on.
Titan but many mountains seen by Cassini have craters at their tops suggesting they may be dormant or in active volcanoes Titan also possesses jagged sharp edged mountains reminiscent of the Alps of the Rockies on earth these mountain ranges known as fault mountains are produced when tectonic plates crashed together and crumpled upwards so their presence on Titan implies.
Something similar might be occurring under its surface Albee it of ice and water rather than rock and lava between 2005 and 2007 Cassini observed surface features on Titan to shift up to 30 kilometres suggesting its surface was decoupled from its interior this likely meant that Titan had an active quote mantle of liquid water and ammonia beneath its frozen surface that could.
Serve as a reservoir for any water lava but therein lies the rub Rock is denser than lava so lava can't wait to burst out from under it liquid water however is denser than ice meaning that it needs some form of additional energy to erupt through it someone claimed that this means cryovolcanism cannot be occurring on Titan others argued the additional.
Energy could come from an external source such as tidal flexing similar to that occurring on Europa but if Titan were proved to be a frozen analogue of our earth in every physical respect is it then possible as how Hans himself had suggested that it might possess that one attribute so far unique to earth life might some alternate cryonic evolution have produced a cycler.
Of philic organism happily swimming in titans frigid methane seas the idea is not as outlandish as you might think and believe it or not we may have found evidence of it already in 2005 an astrobiologist named chris mckay proposed a possible mechanism for life to subsist on Titan's surface Tycho's atmosphere contains no free oxygen which is a very good thing since.
If it did the slightest spark would cause it to react explosively with methane and hydrogen effectively turning the moon into a giant gas bomb most life on Earth requires oxygen to produce energy though there are many examples of extremophiles unicellular organisms found in highly atypical environments that do not one such example is methanogens these single-celled.
Organisms respire hydrogen instead of oxygen and produce methane as a by-product free diatomic hydrogen does exist in Titan's atmosphere and using it McKay showed it is possible to create a successful energy producing reaction with the materials available on Titan one proposed reaction combined hydrogen with ethane to produce 14 calories of energy per unit of hydrogen consume.
Another combined hydrogen with acetylene to produce 80 calories per unit of hydrogen it should be noted at this point that the respiration we use produces nearly 700 calories per equivalent unit of oxygen and without that extra energy any methanogenic life on Titan is unlikely to be larger than your average stomach bug but McCain did more than model his.
Alternate life form he made a prediction about how it might be found if these creatures existed that may would be consuming any hydrogen that came their way and so what manifests as hydrogen levels fell dramatically near the surface and in 2010 Darryl Strobel of Johns Hopkins University found just such a pattern in the hydrogen in Titan's atmosphere though he was quick.
To say that such results were extremely tentative and could be AB non biotic origin the discovery of a methanol biotic life-form on Titan would be one of the greatest finds in scientific history greater even than locating life on Europa or Mars any life on those worlds at least as we surmise it would be comparable to that of our own world using the same chemistry and existing.
Within similar tolerances for such things as heat cold or acidity indeed there is some chance it may even have a common ancestry with terrestrial life having spread between them on meteorites but life on Titan particularly life in Titans exotic Lakes would be of an entirely different order adapted from its molecules up to subsist in an environment so alien that not even our.
Most resilient extremophiles could endure it to compare such life to our own would be to compare a stone fish to a stone there is no way that such life could have shared ancestry with ourselves it would have to have emerged completely independently of life on earth that would mean another confirmed example of abiogenesis in our solar system it would immediately answer one.
Of the standing questions of the Drake Equation how likely is the formation of life on a habitable world and the answer would be almost inevitable if life could form twice in our own solar system and under such vastly different circumstances then we would be mad to assume that it could not do so everywhere there is however one fundamental problem with the concept of.
Liquid methane based life and that problem is water despite my having spent the entire first video emphasizing to you just how common and humdrum water is the simple fact is water is weird like really weird take the fact mentioned above that liquid water is denser than solid water have you ever noticed how strange that is that ice floats on water if you drop a.
Lump of solid iron into a vat of liquid iron it sinks because sods are denser than liquids this is true for nearly every substance you can think of including methane so if you were hoping for an ice-skating trip on Titan you're out of luck if water behaved like a normal liquid that ice would sink to the bottom of rivers lakes and ponds and they would freeze from the bottom up.
Leaving little room for fish what magic allows water to somehow levitate on itself the answer is tied to the one property of water that just might make it uniquely qualified as a solvent for life water's primary role in the sustenance of life is as a solvent it is the medium through which the myriad complex molecules and nano machines that make up.
Ourselves and organs mediate the cascade of evolving interactions that drive our biology and as solvents go water takes some beating in fact water is sometimes called the only true universal solvent because it dissolves more substances than any other chemical everything from salt and sugar to iron copper and zinc all of these substances - various theories are required for life on Earth.
To function and are obtained through their solubility in water also as anyone who is overfilled a kettle knows water possesses a remarkably high specific heat capacity it takes a lot of energy to turn it from a liquid to a gas meaning it stays stable over a broad range of temperatures this not only grants water based life a broad range of potential habitats but gives water a.
Crucial role in moderating Earth's climate as it acts like a storehouse for heat all of these oddities can be traced to one specific property of water it is one of the most polar solvents in existence what that means is that while a water molecule is chemically neutral overall the oxygen atom is so hungry for electrons that it steals them from hydrogen atoms meaning that one side of.
The molecule is positive and the other side is negative it does possesses two poles like a magnet and indeed water is in a sense magnetic if you hold a static electricity source next to a stream of water the stream will be pulled toward it like iron filings to a magnet the upshot of this is that the water molecules famous Mickey Mouse head is in fact a three-legged stool with a third.
Leg made up of a pair of free electrons these electrons create what is known as the hydrogen bond they pull other substances breaking them into their component atoms granting water it's unique dissolving ability they also seek out other water molecules forming weak bonds with them these bonds keep water molecules from moving apart and so demand a great deal of heat before.
Transitioning to a gas conversely they also prevent water molecules from moving closer together as it cools water loses energy and so can no longer overcome the bond and the molecules remain apart which is why ice is less dense than water even beyond this there is evidence that water plays an active role in the functioning of life proteins the building blocks of living matter can.
Assume a virtually infinite variety of formed but within living things they are confined to those forms beneficial to the organism these forms are moderated by water some parts of a protein are attracted to water some are repelled and the presence of water forces proteins to fold in specific required ways liquid methane unfortunately has none of these advantages it is not polar and so cannot.
Dissolve substances like proteins it is liquid over a range of just 20 degrees Celsius compared to a hundred degrees from water but perhaps were being a little too Earth centric here ethane which is also present on Titan is liquid over a comparable range to water waters voracious solubility also means that it breaks down larger organic molecules that would remain stable and liquid.
Methane medium also some have argued that far from assisting the creation of complex molecules the power of the hydrogen bond actually disrupts processes like protein folding meaning that they would be easier in a methane medium and while proteins cannot dissolve in methane poly lipids can and as long as 40 years ago Isaac Asimov suggested that poly lipids.
Could form the basis for biology in a non-polar solvent this does however make forming a cell membrane rather difficult since cell membranes are made of poly lipids precisely because they don't dissolve in water however in February 2015 astrobiologists constructed a hypothetical cell membrane using a substance called acrylonitrile.
Which contains carbon hydrogen and nitrogen called in as otis ohm which literally means light this body but in this case is meant to mean nitrogen body this structure was able to maintain integrity in a liquid methane environment it could possibly serve as an alternative cell membrane finally there is the simple fact that even if life is impossible on Titan.
Surface we know that Titan does possess a liquid water mantle probably as large as the one suspected under Europa Titan could still be home to life of the humdrum terrestrial type perhaps even both the possibilities hidden in the dizzying strange beauty of Saturn's largest moon have ignited dreams not felt since the days before the space program when we imagine beautiful bucks.
And women on Venus and stir and father figures on Mars the thought of an entirely new form of life hidden just beyond our reach has scientists thrumming with anticipation and NASA drawing up distant plans for now eyes are focused on Europa but everyone knows where they'll be going next join me next time when I'll be exploring the rest of this attorney in the system.
And in particular one pint-sized hotshot world who rakish Lee stole the show