Naked Science - Deadliest Planets

in the future humanity may leave the earth behind and search for a new home in space but where our solar system is a dangerous place there are fiery volcanic worlds planets with 1400 mile an hour winds clouds of deadly acid temperatures hot enough to melt landed among these violent worlds are there planets where we could one day live we're on a voyage to find out to explore the planets in our solar system and beyond our mission to hunt for new worlds to find a place that one day we might call home [Music] [Music] imagine a city with 200 billion stars so vast that a jumbo jet would take 100 billion years to cross it we call it the Milky Way on the outer edges of one of six spiral arms is our own star the Sun and it's orbiting planets one planet has life earth with its oxygen-rich atmosphere and oceans of water life can flourish here but our world is changing climate change is melting the polar ice caps sea levels are rising over the next millennia land may disappear under the oceans vast areas could become uninhabitable making the planet dangerously overcrowded we'll need more space if we're all to survive this is a journey through the solar system and beyond hunting for our next home we'll discover a surprising planet that could support life in its atmosphere it is a comfortable temperature and pressure I think that life could exist but there are also deadly worlds where we stand no chance of surviving you couldn't just fly through the system and survive you would fry up finding a new home is not going to be easy we evolved on earth where else will we find a planet we can even survive our journey begins with mercury the closest planet to the Sun data reveals it has an atmosphere with traces of oxygen but could it sustain human life it's surface suggests a violent past [Music] asteroid impacts have left it cratered and scarred but today those impacts are rare they happened four-and-a-half billion years ago at the birth of the solar system asteroids were everywhere junk left over from the formation of the planets impacts were common and some of them were huge on Mercury one left to crater 800 miles across it sent shock waves rippling through the surface a mercury quake the collision was so great it buckled the crust and pushed up a range of hills on the other side of the planet today the solar system is a calm or place the problem with settling on Mercury isn't from the threat of asteroid strikes its temperature mercury rotates very slowly a day here lasts 58 earth days the dark side faces away from the Sun for so long the temperature plummets to a staggering 300 degrees Fahrenheit below zero around three times lower than the coldest temperature ever recorded on earth at the same time the side facing the Sun can hit a scorching 840 degrees as hot as a blowtorch a temperature is so brutal that almost all Mercury's atmosphere long ago evaporated into space what oxygen is left is extraordinarily thin there simply isn't enough of it for us to breathe [Music] there have to be easier places for us to survive maybe we just need to be further from the Sun home the next planet out is Venus Venus is a close neighbor of Earth about 26 million miles away it is shrouded in a thick atmosphere that completely hides the surface from view scientists used to think that would protect the planet from the Sun they imagined Venus's surface to be like early Earth that tropical forests covered the land and oceans of water lapped the shores professor David Grinspoon is an astrobiologist at the Denver Museum of Nature and Science specializing in the evolution of Venus people assume that it was sort of a dripping wet place and in fact the image of a sort of tropical paradise with with tree ferns and maybe even dinosaurs a kind of primitive tropical earth-like place was a common scientific view of Venus really right up until the beginning of the Space Age the Venusian surface intrigued scientists what was really going on beneath the clouds [Music] in the 1960s and 70s while NASA explored Mars the Soviet Union turned its sights on Venus the goal was to land and photograph the planets mysterious surface codenamed Venera the Soviet program made countless successful launches only to mysteriously lose contact with its probes as they entered the Venusian atmosphere but in October 1975 the team hit gold Venera nine beam back the world's first surface images of Venus rather than a lush green world Venus was a barren desert could humans survive here recently astronomers have built up a detailed picture of Venus's atmosphere imagine a probe hurtling toward the planet [Music] what would it see 50 miles above the surface it hits a thick layer of cloud but this is no ordinary cloud it's made of vaporized acid corrosive enough to burn through steel scientists believe that the acid clouds are a byproduct of Venus's violent history gigantic volcanic eruptions blasted billions of tons of sulfur high into the atmosphere there it mixed with water vapor to form concentrated sulfuric acid as the probe breaks through the upper atmosphere it slows to make a low pass over the surface the terrain is dominated by dormant volcanoes the tower 3 miles into the atmosphere deep channels forged a million years ago by molten lava stretched thousands of miles one longer even than the River Nile probe sensors reveal an atmospheric pressure 90 times greater than on earth large enough to crush a car but the biggest problem is temperature the atmosphere is nearly all carbon dioxide just like on earth this gas acts like a pane of glass in a greenhouse letting the light through but not the heat out on earth increased carbon dioxide levels are causing small rises in temperature but on Venus they have pushed the temperature to over 900 degrees Fahrenheit Venus wouldn't be my my first choice of a vacation spot in the solar system you would be simultaneously burnt to death crushed to death and your body would instantly react in a very destructive way with the corrosive mix of toxic chemicals the environment is so savage that any spacecraft will have to be built from materials that can resist Venus's treacherous atmosphere okay that here's some lead this is a metallic substance that we normally think of as a solid on earth but let's see what happens when we heat it up to closer to Venus temperatures you can see it's starting to melt right away so that would not be a good thing to build your Venus spacecraft out of that's why when we make our landing craft of which we've made a few for Venus we have to make them out of these very fancy titanium alloy kind of materials the kind of materials they make fighter jets and things like that out of the don't melt at these extremely high temperatures but surprisingly although the surface is hot enough to melt lead Venus may not be an entirely lifeless world billions of years ago primeval Venusian oceans could have been home to simple organisms some scientists believe that when the temperature climbed the waters boiled away this would have killed many of the organisms but some may have survived by migrating to the cooler clouds in the upper atmosphere Grinspoon believes that if primitive life can survive the acid then surely humans could think people will go ballooning on Venus because all you need of course to go into the clouds of Venus is a decent source of oxygen and some kind of a rubber suit so that your skin doesn't get burned off by the acid it may be possible to glide through Venus's upper atmosphere but surviving on the surface is another matter the high pressure and 900 degree temperatures would instantly crush and burn any settlers [Music] colonizing Venus is not an option we must head further out toward the last of the solar system's inner rocky worlds this time it's one that scientists think that we may just stand a chance of living on but the challenges facing would-be settlers go beyond anything we've ever seen on earth [Music] Mercury and Venus can never support human life on any large scale we pass earth and move deeper into the solar system the next planet is Mars could we one day settle here Mars is the one world that most resembles our own a Martian day is almost the same length as ours Mars has mountains deserts and gaping canyons cut in the distant past by running water traces of that water may still be locked beneath the surface but to reach it we would have to face an ancient danger radiation five billion years ago when our son was born it blasted high-speed energetic solar radiation out across the whole solar system and it's still doing it today without some sort of protection we could not possibly survive [Music] we were lucky our world developed a magnetic field this shield deflects deadly solar radiation away from the surface but Mars has no magnetic field and that means no protection over many millennia the solar radiation ripped the atmosphere from the planet Mars as water boiled and most of it evaporated into space the surface became a barren desert for any future human visitors to the Red Planet solar radiation will be a deadly hazard even with the protection of a space suit the radiation can still penetrate it tears through the body bombarding and killing living cells destroying DNA if humans are to live and work on Mars a surface will need some serious protection so scientists are developing drugs astronauts would take these specially designed enzymes to mop up the radiation Martian homes would need shielding two scientists have developed a special form of polyethylene plastic lighter and stronger than metallic shielding yet just as effective the plan is to build it into the structure of Mars habitats protecting the occupants with this advanced technology humans could one day consider populating Mars but there's another hazard to overcome after the radiation stripped the water from the surface the planet was left covered with dry iron oxide dust meet the sandstorm Martian style these mini twisters are babies dust devils just powerful enough to suck dust up into the atmosphere the problem is what happens next professor Ron Greeley has been studying atmospheric activity on Mars for over 30 years knowledge vital for any human expedition to the Red Planet Greeley uses a fan and frozen nitrogen vapor to recreate these twisters in the lab they form when the Sun heats the surface causing a pocket of hot gas to suddenly rise spinning through cooler air above it sucks up fine iron oxide dust and punches it high into the Martian atmosphere the dust devils range in size from about a yard across to features that are are as large as a football field in diameter these can be quite large that dust has to go somewhere Greeley believes the mini twisters could trigger much bigger storms we do in fact see local dust storms that growed of global proportions clusters of individual dust storms that that eventually merge the entire planet is enveloped in dust and we can't even see the surface through through that dust but it's not just dust devils that can trigger trouble on a global scale in blowing across the surface can kick up dust into the atmosphere building into an overwhelming storm this also happens on earth satellites photographed a storm raging across the Sahara Desert in Africa revealing its enormous size the similarity with the storm on Mars is striking and that much dust is going to cause problems when humans go to Mars they have to be concerned about the infiltration of this very fine dust it's sort of like baking flour if you will very very fine-grained the dust is so fine that even the slightest wind can blow it anywhere clogging up machinery and air supplies not only is the dust likely to get into every nook and cranny but there are also properties of the dust that may pose a hazard one of the considerations are the electrostatic charging effects with little tiny grains banging together electrical charges are built up much like shuffling your feet on a carpet the rubbing action between the grains of dust creates enormous static electricity up to 20,000 volts can spark between the dust particles this could destroy electronics and life-support systems when we think about the eventual human presence on Mars we have to understand the dust regime we have to understand the electrostatic effects all related to windblown particles perhaps one day we will conquer Mars as harsh environment but this is not a world that would ever feel like home we leave Mars and push on out toward the super-sized worlds of the outer solar system the gas giants these offer new and even more extreme challenges in our quest for another home first up is Jupiter Jupiter is a mysterious world so vast that 1300 earth sized planets could fit inside it it's entirely made of gas it has no solid surface at all its upper layers are a mass of swirling counter-rotating clouds this is a planet wracked with storms and high-speed winds professor Fran bagging owl has spent a lifetime studying the atmospheres and environments of Jupiter and its moons jupiter is spinning extremely fast it rotates every 10 hours and so rotation is very important and drives over east-west winds are that produce the belts and the zones their stripes across the planet Jupiter's high speed spin generates horizontal bands of clouds that wrap around the planet like a belt when these cloud bands collide they create massive storms the biggest of these is the Great Red Spot the largest storm in the solar system as we approach the scale becomes clear it's three times the diameter of Earth near the spots boundaries turbulent spills around the edges winds here travel at more than 250 miles per hour it's true that it has a lot of similarities with hurricanes in that the outer edges it's swirling around a lot faster and so indeed the inner parts are more calm at first glance the red spot looks similar to hurricanes but there is a difference here on earth hurricanes feed off the warm waters of the ocean but as soon as they hit land they start to die our storms only lasts about two weeks but Jupiter's different the red spot has been raging for over 300 years the reason why we lost such a long time is there isn't a surface on on Jupiter so it's not as if storms run into a continent and dump its its energy it just keeps going and going and going around in the world but the spinning of Jupiter is not enough on its own to drive the Great Red Spot scientists discovered the planet gives out twice as much energy as it receives from the Sun suggesting its core must be hot this Center could be the powerhouse that drives Jupiter's winds the core could be worth a closer look as we descend through upper layers vast water clouds envelop our craft the pressure is climbing toward the center it transforms the hydrogen atmosphere to a strange liquefied metal resembling the element mercury this is the core a churning furnace at over 40,000 degrees Fahrenheit scientists estimate that the pressure here is 100 million times higher than on the surface of Earth how can I give you a sense of what that feels like as a pressure well if anyone's had someone step on their toe with us to Leto he'll you know that's a lot of pressure now imagine an elephant wearing stiletto heels and standing on one foot honest to let over he'll but to get the pressure at the center of Jupiter you need to have about a thousand elephants standing on top of each other the bottom one on one foot on a stiletto heel [Music] at these sorts of pressures humans could never journey to the core but could we survive in the upper atmosphere the answer to that lies on one of its moons which has an extraordinary effect on the gas giant it might be dwarfed by Jupiter but this minuscule world packs a mighty punch [Music] our quest for a new home has brought us a long way we are 365 million miles from Earth in orbit around the giant planet Jupiter could we survive here perhaps in the turbulent upper atmosphere that depends on what's happening around us on Jupiter that means looking at its moons IO is tiny but it's the most volcanic body in our solar system and living next to a volcano is never a good idea dr. Rosalie Lopez is a volcanologist she's come to the Kilauea volcano range in Hawaii one of the closest matches on earth to iOS fiery surface this is very much what the surface of Io may look like particularly close to the lava flows there would be lava flows just like this solid at the surface with underneath first hot lava flowing like Kilauea io spews lava from its superheated interior but that's where the similarity stunts the volume of lava that iris volcanoes erupted is quite staggering if we do a comparison with Kilauea in five months Kilauea might cover four square miles but I whoever ups about a hundred times the volume of lava one lava flow and I are covered two hundred and forty square miles iOS volcanoes are deadly but they aren't the real killer before the lava can get you the radiation will just ten minutes on the surface and you're toast even over 200 thousand miles away in Jupiter's upper atmosphere an unprotected human could only survive a matter of hours the volcanic particles that IO blasts out into space become trapped in Jupiter's enormous magnetic field Jupiter's rapid rotation accelerates them to fantastic speeds they're like microscopic cannonballs they form a radiation belt around Jupiter cutting through almost anything in their path they're sufficiently intense that a human would receive a lethal dosage within just 10 minutes so you couldn't just fly through the system and survive you would fry on them this intense bombardment would destroy your flesh and the organs inside everything [Music] we just don't have the technology to protect ourselves from radiation this fierce jupiter is one planet will never call home could our next stop offer more hope Saturn's radiation levels are lower but it's not a danger free zone from Earth Saturn appears almost featureless but its appearance is misleading its rings may look solid but in fact they're mostly made up of billions of chunks of ice and rocks ranging in size from pebbles to blocks as big as a car all of them are moving faster than a high-speed bullet but Saturn's real danger lies within its atmosphere like Jupiter the planet has bands of high-speed counter rotating winds clouds race around the planet at over 1,000 miles per hour along the edges were two bands meet tiny particles collide rushing past each other generating an enormous electrical charge theory suggests that when the charge gets to great the electricity arcs between the clouds producing giant lightning bolts NASA's dr. Kevin grazier is a planetary scientist who specializes in atmospheric conditions on Saturn we have a chance for a lot of charge transfer between one band and the other creating large voltages creating huge lightning bolts to get an idea of just how huge Saturn's bolts are compare them with earth lightning here can hit 50,000 degrees Fahrenheit in a split second striking the ground it's hot enough to create a tube of solid glass stretching down 15 feet but compared to Saturn that's a tiny spark a single storm on this gas giant can cover the whole of America and you can also get storms at last for years storms on earth last for week or two storms and Saturn last for weeks months years with such an unstable atmosphere even attempting to enter Saturn's clouds is deadly as we push out and pass the featureless world of Uranus we're heading for the very edge of our solar system and out here there are challenges that will test human visitors to their limits and beyond in the future humankind will journey to distant worlds searching for new planets we could live on next stop Neptune and over three billion miles from Earth observing this gas giant is a tough job so astronomers go high very high way above Earth's clouds and pollution to get a clearer view this is the Keck Observatory 14,000 feet up on the summit of Mauna Kea in Hawaii the telescope's here are so powerful they could see a flickering candle on the surface of the Moon dr. Heidi Hammel has been researching Neptune for over 20 years coming to Keck gives her the chance to study this distant world it's a beautiful blue planet but that blue is not water like on our planet that blue is the atmosphere of hydrogen a little bit of helium and most important a smidgen methane Neptune may not have water but it does have clouds and these clouds allow Hammel to discover whether humans could survive this alien world standing out against the blue atmosphere the clouds are easy to see they form when methane freezes in Neptune's super chilled upper atmosphere the Keck telescope swings toward Neptune [Music] Hamill takes a series of photographic shots tracking the white clouds as they move around the upper atmosphere measuring the time and distance they move between two points she can calculate just how fast the winds are blowing the result comes as a shock some of the winds that we've clocked on Neptune do seem to be some of the fastest in the solar system some of these little white puffy clouds that we've tracked are really fast they blow almost as fast at some latitudes as 1,200 miles per hour in our quest for another home one thing is clear humans could never visit this alien world yet there is a near neighbor a world without storms and with a solid surface [Music] this is Triton one of Neptune's 13 moons super chilled and covered in frozen nitrogen snow it would be big enough for us to live on the question is could we dr. John Spencer from the Southwest Research Institute in Colorado has been exploring the life-threatening hazards of tritons icy climate the surface of Triton is probably quite is our close-up we have frozen carbon dioxide frozen carbon monoxide frozen methane on the surface but also a great deal of frozen nitrogen it might form snowdrifts and be crunchy and afford any human exploration of Triton savage surface is life threatening at 390 degrees Fahrenheit below zero we'll need some special space gear with assistant Eddie goldstein Spencer uses liquid nitrogen to replicate Triton's environment it allows him to see how materials will behave on this supercooled world if you were to build a spacesuit that would function at frightened temperatures you need something kind of flexible to make it out of you might think you might use some kind of rubber material at room temperature rubber is soft and pliable ideal for creating airtight seals on astronaut life-support systems but drop the temperature to minus 350 degrees Fahrenheit and it's a different story and just because something is flexible on earth does not mean as flexible on Triton the rubber molecules are flexible at warm temperatures but drop them into chilled nitrogen they become rigid as steel the rubber hardens and shatters like glass the search is on for materials that remain flexible at super low temperatures scientists are looking at familiar substances fabrics that you may be wearing at this very moment could not be used in the super chilled world of deep space and it's interesting because it's just as flexible even after it's cold and it's not because nylon is anything special it's because the nylon was woven into tiny threads the secret of the nylons flexibility lies in the weave the fibers remain pliable because each strand is as thin as a human hair so you might be able to make suits out of some material like this if you just treat it in a different way that takes into account this very unusual environment that we have out there even if humans do manage to walk on the surface in high-tech spacesuits there is one other danger lurking beneath Triton's surface [Music] what we see is these rather vague streaks Jets of material coming up from the surface these dark marks are the clues to Triton's hidden Menace beneath the frozen surface lie oh she's of liquid nitrogen as the Sun warms the moon the nitrogen turns to gas this pressurized gas explodes as a geyser blasting moon dust high into the atmosphere the black dust finally settles on the white surface leaving dark streaks back in the lab Spencer recreates the spectacle so what we're going to do is put the nitrogen in a situation where it's contained within this flask just as it might be trapped underneath a layer of glaze ice on Triton itself and the pressure would build up and that would produce a jet that could maybe shoot up six or ten miles just like hey we've got the geyser just as the pressure builds in the glass flask on triton pressurized nitrogen trapped under the surface blasts moon dust into space a world the violent geysers and crushing cold with the right technology humans could one day walk on the surface but it's not a world we could easily colonize within our solar system this is the end of the search [Music] this far from the Sun any planet is cold and barren after neptune there are only small dead icy worlds like pluto beyond is the unknown out here the possibilities are endless and out here perhaps we will one day find a place to call home you today astronomers are piecing together incredible new evidence in the search for distant worlds planets that could support human life our Sun is only one of 200 billion stars that make up our galaxy the Milky Way any of these stars could have planets just like our solar system tracking them down is the ultimate scientific quest and king of the planet hunters is dr. Geoff Marcy our Milky Way galaxy is a glorious but enormous place it contains 200 billion stars and it's a hundred thousand light years across and so we have to pick and choose which stars to observe this is the Lick Observatory in California where planet hunters like Marcy come he scans the night sky searching for new worlds orbiting distant stars but he has to pick carefully luckily there's this marvelous catalog called the Hipparcos catalog that has over a hundred thousand stars that are all very nearby and what we've chosen logically are the nearest in fact the nearest 2,000 stars they're all within about two or three hundred light-years of the earth okay Bernie I think we can go to the next star the next one will be Barnard star every star takes hours of painstaking observation licks three meter telescope locks on to its target but even with all its magnification a planet circling a distant star is too small and faint to be seen directly the real challenge in Planet hunting is that planets by their intrinsic nature don't produce their own energy they shine by reflected light and if they're warm they glow a little bit but they are in fact about a billion times fainter than the host star around which they're orbiting so astronomers have perfected an ingenious technique to find these invisible worlds so we use a trick and the trick is we watch the star not the planet as a planet orbits the star the planet pulls gravitationally on the star making the star wobble to and fro to show how a planet pulls on a star marci uses a simple demonstration okay so here we have a bag of rice and it's going to simulate the planet and I'm the star and what happens of course is that the planet orbits the star like so and as the planet orbits the star the planet pulls back on the star and makes the star wobble you might be able to see my body wobbling back and forth and it's wobbling because in fact the sack of rice is pulling on me and of course the analogue is quite perfect because the sack of rice acts as the planet my body is the star and this rope serves as gravity and of course all we see with our telescopes is the star we can't detect the planet at all so we just watch stars to see if they wobble to and fro and if they do they must have a planet to date hunters like Marci have found over 200 new planets orbiting distant stars but can they determine what those worlds are like Marci believes so by calculating how far the new world is from its star the longer it takes the planet to go around the star the farther the planet must have been from the star close in planets go around fast distant planets take a long time the earth of course taking one year he's discovered one world 1,100 times the mass of Earth but orbits eight times closer to its parent star another planet is so close it races around in just three days making its surface thousands of times hotter than Earth some of the planets we've found orbit so close to their stars that the temperatures are thousands of degrees at those kinds of temperatures ordinary metals like iron and nickel and titanium not only melt they vaporize instead of clouds of water the atmospheres of these deadly worlds are filled with clouds of metallic vapour but Marcy's convinced that not all alien worlds are so savage he's decided to look at smaller stars that burn less intensely could they are orbiting worlds be more like earth what we hope to do in the next year is is a glorious quest we're going to observe low mass stars and hunt for earth-like planets they're orbiting close but next to a dim star the temperature won't be too hot nor too cold but just right for life out here countless worlds are waiting to be discovered perhaps some will have breathable atmospheres and oceans of water allowing life to flourish but finding them is a huge challenge so far scientists have drawn a blank and judging by the deadly environments on the planets that make up our own solar system it's not going to be an easy job the crushing heat of Venus - the erupting volcanoes of Io - the 14 hundred mile per hour winds of Neptune the worlds we have discovered are too savage for even our most advanced technology the only planet that offers hope for human colonization is Mars if we could overcome the dust and the solar radiation one day we could live here maybe in the future when Earth's climate is too extreme Mars will become home until that day humans will have to adapt continuing to thrive in a constantly changing world [Music] you [Music] you

Channel: Naked Science

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Keywords: deadliest, planets, hell, naked, science, world, alien, environment, violent, dangerous, place, solar, system, weather, human, technology, nearest, journey, interstellar, star, trek, beyond, characteristics, planetary, life, edge, universe, space, travel, venus, jupiter, discover, formation, deadly, existence, survival, atmosphere, mercury, temperature, orbit, dark, side, coldest, hottest, brutal, acid, clouds, mysterious, probe, savage, radiactive, hazardous, mars, storm, giant, neptunian, moon, milky, way, galaxy, astronomy, worst, furthest

Id: rD5oDjk3IOU

Length: 46min 7sec (2767 seconds)

Published: Wed Jul 31 2019