Astrobiology: The Search for Life Beyond Earth | Marta Filipa Cortesão | TEDxUniversityOfPorto

[Music] when you think of life in other worlds what do we immediately start to imagine something like this right little green men and tall super intelligent species that comes in a spaceship ready to invade Earth well have you ever wondered what we really know about life in the universe people have looked at the skies and wonder about the possibility of life in other worlds for centuries but it was only in the 50s in the 1950s space age where a molecular biologist named Joshua Lederberg that first introduced the term eggs abaya Lodging to define the study of the biological impact of the space missions and to define the study of the search for the extraterrestrial life so back then space was a very hot topic right and leatherwork took the chance and team up teamed up with Carl Sagan also and together they brought eggs or biology to the public and to the scientific community community and the field began to gain recognition so space exploration developed technology evolved and so did the search and the science of the search of the extraterrestrial life and it's developed until what we know today as astrobiology so astrobiology is the science that studies the origin distribution and evolution of life in the universe and it takes several branches of science biology geology astronomy physics chemistry but also engineering and sociology and together we all come together as scientists and study life but in a cosmic perspective so how do we do it well if we want to speculate about life in other words what it could be the only logical starting point is to start by looking at our own planet right because for now the only planet that has life is Earth so what we do is something called the great analogy and in here we use all the knowledge that we have from life on Earth how it originated how it evolved what it looks like now in which environments it lives in and we extrapolate this knowledge to other environments in the universe to extraterrestrial environments to what other places of our solar system and beyond so the origin of life on Earth is one of the key main happenings for astrobiology because if we understand how life began here on earth then we know what it takes for life to have emerged in other places right so on earth life is thought to have emerged around 3.8 billion years ago and back then earth was not the same as today there was no oxygen the ozone layer wasn't there so we had a lot of radiation and so the first forms of life would have to be anaerobic so they would have to be able to grow up without oxygen and they would have to find a way to protect themselves from themselves from the radiation this means that one of the possibilities is that life was first originated in the deep oceans where the radiation wouldn't heat so okay what it takes for life to emerge at least as we know now two things liquid water and organic molecules so on early Earth what we think is that the oceans would bring the molecules around the tides would bring the molecules around and eventually the right molecules met at the right time at the right place and life emerged the planet Earth evolved there are many different life forms now right and biodiversity really is pushing forward because every day we find new organisms that live in places that we thought no life could ever exist they are so extreme these guys are called the extremophiles these are just some examples of microorganisms that live from temperatures from minus 20 degrees to above 100 they live in very acid rivers or very salty lakes and these extremophiles are essential for astrobiology because they help us set the limits of life we hope they help us understand in which environments life can actually exist one of the most extreme environment is actually space so here on earth we have the ozone layer as I said the magnetic field that keep us protected but once you go up and you leave the ozone layer and you leave the magnetic field you get hit by the space radiation solar cosmic radiation you get hit by the space vacuum you get hit not hit but you are in microgravity you would have no gravity and astronauts that are in the International Space Station they know this very well temperatures are very difficult to control as well so one of the things that we want to know is can life survive in space we have been doing a lot of experiments many of them are simulation so we have ground-based facilities that simulate the space radiation the space vacuum but we have also done a lot of a lot of experiments in situ so we have sent bacteria and other microorganisms to space we have put them on the outside of the International Space Station where they are exposed to the real space vacuum and the real space radiation so they stood there for months and what we found out is that many of them actually survived so this raises the question if life survives to the extremes of space where else can it be what other environments can be habitable so the first place we actually look of course is our own solar system we begin by looking at the moon we went there there is not these teams there is no life there but then we focus on other things now our favorite second or second favorite planet is Mars but also other moons of Jupiter or Saturn are beginning to raise interest but what really gives astrobiology an interesting twist was the discovery of the first exoplanet exoplanets are planets that are outside of our solar system in other planetary systems the first one was only found in 1995 before that we had no confirmation that a planet existed outside of our solar system so after that with the use of mainly of the Kepler telescope we discovered a lot more exoplanets one of the first was actually named Kepler 16 and it became quite famous but only because it was similar to the planet Tatooine of star wars it had two sons it looks familiar now with all of these exoplanets we can know what other environments are there we can check for habitable conditions but there is one it's one of my favorites that is right here in our solar system that is the Jupiter's moon Europa it represent wristing but mainly because it has a big ocean this ocean has about 100 kilometres long is like three times bigger than Earth and it it's covered by a nice crust similar to what happens on earth we have an ocean and a crust and the crust of Europa is made of ice this ocean so on earth our tides are created by the gravitational pull of the moon right on Europa and you can see there the tides are created by the gravitational pull of Jupiter giant giant Jupiter so you can imagine that the tides are very very fast very dynamic and they moved the crust around it clashes almost in a catastrophic way and this if you look at the scenario what we have here liquid water right so it's starting to look good maybe some organic molecules are already there and we already have the movement of the tides that can bring the right molecules together at the right time maybe in the right conditions and although the this ocean is known to be very cold and very salty we already know some microorganisms that live in similar conditions such as this guy so who knows maybe Europe already has an extremophile waiting to be found there is many Me's there are many missions planned also with the European Space Agency's planning some one of them is the Jupiter ices icy moons explorer juice that is going to blight fly by Jupiter and its moons and hopefully we'll find something more about it there is also ExoMars that is one of the first European missions that is dedicated to astrobiology and will look for signs of life on Mars but next time that you think of life in other worlds maybe you will start thinking of these guys instead thank you

Channel: TEDx Talks

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Keywords: TEDxTalks, English, Portugal, Science (hard), Astronomy, Biology, Science

Id: K-N0_kMvtFU

Length: 8min 49sec (529 seconds)

Published: Tue May 09 2017