Transcript

The Most Extreme Life Form in our Solar System | David Baker | TEDxAustinCollege

good afternoon a few years ago another professor and I led a group of students on a remarkable adventure we explored a slot canyon in the Blue Mountains of Australia teeming with vegetation and relatively untouched by humans the only way out at the end of the canyon rappel down a 100-foot waterfall I have never been more focused ok terrified then when rappelling down that waterfall the roar of the water the search for each slippery foothold the burn of the rope in my hand as I held on way too tight yeah but the coolest thing of all was the canyon itself giant ferns hundreds of years old clung to the canyon walls walls that would almost straight up sometimes the vegetation was so thick that the sunlight barely made it to the canyon floor below it was dark and the sound the sound was different muted it was like going back in time a bit like Jurassic Park you could easily imagine a wild creature just lurking around the corner that same sense of adventure has led us to explore well beyond our home planet throughout the ages we've looked at the night sky and wondered what is out there and more recently the exciting field of exobiology has emerged life out there what strange extraterrestrial life might exist in our solar system not in a galaxy far far away but nearby in our solar system just around the corner in our slot canyon in this vast universe what is the most extreme life-form in our solar system we are closer to these answers than ever before recent scientific discoveries from Mars from Jupiter's moon Europa and from everybody's favorite former planet Pluto discoveries that shed light on what extreme life-forms may exist out there and of course we need to look at our own home planet earth to gain some insight about what it really means for a life-form to be extreme we have always been fascinated by the red planet Mars and the possibility of an advanced Martian civilization Percival Lowell in the 19th century built an observatory in Arizona whose primary purpose was to search for Martians he saw these linear features canals and attributed them to an intelligent Martian civilization it was really just an optical illusion a trick of the mind caused by the low resolution of the telescope's at the time later more powerful telescopes did not see these canals and spacecraft that visited the red planet in the late 60s and 70s didn't see them either but the spacecraft did see this imagine for a moment it's 1976 you work at NASA's Mission Control the Viking spacecraft is sending back this image you would be the first person to see this what would you think you might think hey that's a face on Mars at least that's the g-rated version of what you're thinking this image created all kinds of excitement many people thought it was evidence of an intelligent Martian civilization because after all a civilization with any smarts is going to build a shrine to a human face but with any scientific endeavor we needed more data every time NASA or the Soviet Union or the European Space Agency planned a mission to Mars they had to consider visiting the face on Mars many missions did and in fact here's an example from the European Space Agency's Mars Express in 2006 the face on Mars looks remarkably like a hill the human brain has this amazing ability to make connections but sometimes we see patterns where they don't really exist here's an image taken by aircraft as it flew near Medicine Hat and Alberta Canada obviously it's a shrine to a human this time a Native American Jam into his favorite music we're in earbuds in fact it's a valley with a dirt road running down the middle leading to an oil well so great Martian civilizations did not build canals or shrines to human faces if there is life on Mars if it is probably in microbial form the best analogy occurs here on earth in the Atacama Desert in Chile the driest place on earth here microbes go in and out of hibernation based on the availability of water this is in the salt flats of the Atacama Desert conditions on Mars are very similar there are salt flats these would be the prime locations to discover Martian colonies of microbes perhaps a better place to find complex life would be a Jupiter's moon Europa water is a key ingredient for life at least life as we know it and that's what makes Europa so interesting the Jupiter the moon of Jupiter is covered with water ice carved with deep canals deep surface deep cracks in it it looks a lot like a glacier but underneath this glacier exists a deep liquid water ocean there is more water on Europa than there is on earth not only that at the bottom of Europa's ocean is a rocky surface active geothermally caused by the strong gravitational pull the tugging of squeezing of the giant planet Jupiter Europa is not the only place that has a deep ocean this is an image of Pluto taken by the new Horizons spacecraft just last year as it flew by the planet dwarf planet notice the heart-shaped region yes Pluto we love you too even if you are a dwarf planet this heart-shaped region is completely smooth resurfaced by water and then refrozen this water comes from below you can think of this underground ocean as continually hydrating Pluto's lovely skin because without it Pluto would be a shriveled up dry planet with deep wrinkles we now believe that many icy bodies in the outer solar system have deep liquid water oceans this raises intriguing possibilities about the search for extreme life why because at the bottom of our own ocean near hydrothermal vents near geothermally active areas there exists this bizarre ecosystem that does not depend on sunlight for its energy rather bacteria take normally toxic compounds and convert them into energy through a process called chemosynthesis not photosynthesis this serves as the base of the food chain for this thriving ecosystem giant tubeworms blind shrimp because there's no sunlight a ghostly octopus that drifts by if we have this bizarre ecosystem at the bottom of our own ocean imagine the possibilities at the bottom of Pluto's ocean or Europa's ocean now no doubt that life would look dramatically different than what is at the bottom of our own ocean and that would really be awesome to discover but it's unlikely that this life is intelligent we have visited these places there is no evidence of a giant radio tower and I'm pretty sure there's no pokemons go on Europa and then there are the tardigrades the water bears these are animals not microbes about the size of the width of a human hair you remember that slot canyon in Australia it was likely teeming with water bears in fact if you go to a stream near your home and you run your fingers through the moss you will likely have water bears underneath your fingernails and they are virtually indestructible you can boil them you can freeze them you can zap them with radiation the European Space Agency has sent them on a rocket and exposed them to the vacuum in the intense radiation of outer space and they survived so if a water bear can survive the hazards of outer space what is that this mean about the possibility of a microbe or even a tiny animal hitching a ride on a comet and taking a tour of the solar system now this would not be an intentional journey this would be an accidental journey not a smart well-planned vacation if you really want to see the most extreme life-form in our solar system you don't have to go to Mars or Europa or even a creek behind your home you just need to look right beside you or in the reflection of your computer screen look very closely that's right you are a pretty extreme life-form things that you consider normal for the overall scheme of the solar system are completely off the charts take this TEDx event for example your brain is electric with activity billions of neurons are firing making connections storing information thinking deeply being extreme your brain is recording this moment and this one and this one and this one hopefully you'll remember it if you hours from now or a few days a few weeks even a few years just think of the memory card that would be required for your video camera to store everything that you're learning today and tomorrow and the next how are we able to have this intense brain activity well for starters our erect posture allows our pretty big cranium to be supported by our skeleton cows don't have the same advantage their head has to be split supported by strong neck muscles as a result their heads not quite as big cows are just not that smart now let's not get too big-headed we don't have the largest brain the sperm will easily wins that contest we don't even have the largest relative brain size a mouse for example has a larger brain relative to its body size don't get me wrong our brains are pretty big but the difference is the complexity of our brain we have more neurons in our cerebral cortex than any other mammal and these neurons are high-quality think of them as monster cables in your brain that allow for great transmission and strong connections complex wiring this complex wiring this brain activity allows us to do some great things the pinnacle of human achievement the Pyramids of Giza the rolling wheel cookies and cream ice cream things that you consider normal a no-brainer in fact like vegging out in front of the TV that would be an intense and demanding experience for any other species because during that no-brainer your brain is still electric with activity we remember the past and plan for the future and we have the ability to change the surface of our earth the view of Earth from space looks dramatically different than it did just 100 years ago a blink in geologic time we have the capacity to change the world but we have to be smart about it in other words we have to be extreme today we've learned that humans are capable of great things consciously deciding to pursue happiness consciously deciding to improve our health consciously deciding to go beyond ourselves beyond our one square meter of space to make the world more fair for everyone and we are the only species to consciously intentionally decide to explore beyond our home planet and leave it while I do think that in our lifetimes we will discover extraterrestrial life and what a historic and humbling day that will be most likely it will be a microbe because if there were intelligent life capable of exploring other worlds we would have already discovered it or it would have discovered us so as far as the rest of the solar system is concerned we humans we are that wild creature lurking just around the corner we are the caretakers of the solar system so let's be smart let's be extreme be the most extreme life-form this solar system has ever seen thank you you