Space has always captured humanity's collective imagination among the pantheon of celestial bodies that have fascinated us Jupiter stands out as the largest planet in our solar system it's vibrant stripes and prominent Great Red Spot making it easily recognizable but there's far more to Jupiter than its size and famous storm and our knowledge has grown exponentially with advancements in space technology and exploration Jupiter is a gas giant consisting mostly of hydrogen and helium its diameter is approximately 11 times that of earth and it's so large that over 13 Earths could fit inside it despite its size Jupiter has the shortest day of all the planets rotating on its axis every 9.9 hours Jupiter's magnetic field is the strongest of any planet in the solar system created by electrical currents driven by its fast rotation and the movement of metallic hydrogen within its outer core Jupiter's famous bands are actually high pressure zones characterized by lighter colored clouds conversely its darker regions are low pressure zones the vibrant colors we see are due to different types of clouds ammonia crystals create the white bands while other chemicals produce the reddish brownish and yellowish hues as for the Great Red Spot this iconic feature is a persistent high pressure region in the atmosphere resulting in a storm that's been ongoing for at least 300 years the Great Red Spot is one of the most recognizable features of Jupiter the largest planet in our solar system at its widest point it stretches 1.3 times the diameter of earth although its size varies over time notably it has been shrinking in recent decade the storm has been continuously observed since the late 19th century but historical records suggest its existence for at least 300 years the Great Red Spot is located in Jupiter's southern hemisphere nestled within a westward moving jet stream called the South Equatorial Belt the red color of the Great Red Spot is still a subject of research it's thought that the color may come from complex organic molecules red phosphorus or possibly compounds containing sulfur the exact chemical reactions that give the spot its vivid color remain a mystery the storm rotates counterclockwise with a period of about 6 days interestingly the rotation speed size and color of the spot can change reflecting the storm's complex interaction with its surroundings the longevity of the Great Red Spot is intriguing while storms on earth last for days or weeks at most the Great Red Spot has persisted for centuries this longevity is likely due to Jupiter's rapid rotation and lack of a solid surface which minimizes frictional dissipation of the storm's energy the Great Red Spot is a window into the atmospheric dynamics of Jupiter a gas giant with conditions vastly different from our home planet understanding the celestial malestrom not only unravels the secrets of Jupiter but also sheds light on the broader principles governing atmospheres including our own Jupiter's four largest moons Io Europa Ganimede and Calisto are known as the Galilean moons named after Galileo Galilei who discovered them in 1610 each of these moons is a world unto itself Io is the most volcanically active body in the solar system its surface covered in sulfur and sulfur dioxide giving it a colorful mottled appearance Europa has a crushed device and scientists believe it might harbour a subsurface ocean making it a potential site for extraterrestrial life Ganimede the largest moon in the solar system is the only moon known to have its own magnetic field Calisto characterized by an extremely cratered surface is believed to have an ocean beneath its surface as well Jupiter was known to have 79 moons but additional moons may have been discovered since then Saturn isn't the only planet with a ring system although much fainter and smaller Jupiter also has rings composed mainly of dust particles from impacts on the planet's small innermost moons these rings were first discovered by NASA's Voyager 1 spacecraft in 1979 the study of Jupiter has come a long way since Galileo's first observations multiple missions such as Pioneer 10 and eleven Voyager 1 and 2 Galileo Juno and more have been sent to Jupiter to study its composition magnetic field and moons Pioneer 10 and 11 were the first spacecraft to make a close approach to Jupiter providing valuable data about its radiation belts magnetic field and some moons Voyager 1 and 2 made significant discoveries such as detecting Jupiter's rings and confirming iOS volcanic activity the Galileo orbiter spent eight years studying the planet and its moons and the attached probe made a direct plunge into Jupiter's atmosphere providing the first direct measurements of its composition the Juno mission still ongoing as of 2021 has made significant contributions to our understanding of Jupiter's internal structure atmosphere and Magnisphere Jupiter the colossal gas giant remains a focal point of curiosity for astronomers and space enthusiasts alike it's impressive size complex atmospheric dynamics multitude of moons and faint ring system make it a fascinating object of study as we continue to explore Jupiter through telescopic observations and space missions we unravel the secrets it holds enriching our understanding of the cosmos for now we marvel at the celestial symphony Jupiter conducts its presence a testament to the intricate diverse and vast nature of our solar system Venus is nearly identical to worth in size making it one of our most similar neighbours in the solar system with a mean radius of about 3,760 miles or 6,052 km it's approximately 95% the size of earth it's mass is about 81.5% that of earth this similarity in mass in size means that Venus also has a comparable density to earth approximately 5.24 grams per cubic centimeter implying a similar rock iron composition Venus and earth have a comparable structure a central iron core surrounded by a rocky mantle and a thin crust the core of Venus while not as well understood as that of earth is believed to be partially liquid similar to earth this iron core is estimated to be about 2,000 miles or 3,200 kilometers in diameter above the core lies Venus's mantle composed of silicate rock that extends up to approximately 1,550 miles from the planet's center this is overlaid by a thin crust estimated to be 6 to 12 miles thick the rotation of Venus is a unique characteristic among the planets of our solar system unlike most other planets which spin on their axis in the same direction that they orbit the sun Venus rotates in the opposite direction this is a phenomenon that isn't yet fully understood by scientists but some believe it may be due to a massive collision with a celestial body in the past which altered the planet's rotational dynamics Venus rotates extremely slowly with a sidereal day a full rotation on its axis taking 243 Earth days the slowest rotation of any planet in the solar system this slow rotation contributes to the planet's lack of a significant magnetic field another quirk of Venus's rotation is that a solar day on Venus the time from one sunrise to the next is shorter than its side real day due to its retrograde rotation and orbit around the sun the solar day on Venus is about 116 75 Earth days the planet's year the time it takes to orbit the sun is about 225 Earth days which is shorter than its sidereal day this makes Venus one of the few planets where a day is longer than a year the surface gravity on Venus is about 90% of the surface gravity on earth this means that if you were able to stand on Venus you would feel slightly lighter than on earth however the extreme atmospheric pressure and temperature would make it impossible for humans to survive without Protection Venus's surface appears to be geologically young with a relatively low number of craters indicating a surface age between 300 million and 600 million years old scientists believe that Venus undergoes a cyclical process where heat from the planet's interior causes the surface to be repaved in a global resurfacing event there is strong evidence of widespread volcanic activity on Venus thousands of volcanoes dot its surface ranging from less than a mile in diameter to over 150 miles or 240 kilometers the planet has far more volcanoes than any other in our solar system however there's currently no definitive evidence that these volcanoes are still active although recent studies suggest that some may have erupted within the last few million years despite the apparent geological activity Venus doesn't experience significant tectonic activity like earth while Venus does have mountain ranges and rift valley similar to those seen in tectonically active regions on earth it lacks the kind of large distinct tectonic plates seen on our home planet this might be due to the planet's slow rotation which limits the Coriolis effect necessary to drive large scale tectonic activity Venus's atmosphere is one of its most distinctive and intriguing characteristics the atmosphere is primarily composed of carbon dioxide 96.5% with most of the remainder being nitrogen however there are also traces of other gases such as sulfur dioxide water vapor carbon monoxide argon and helium this composition is vastly different from Earth's nitrogen oxygen atmosphere making Venuses air toxic to humans and most known forms of life the atmosphere of Venus is arranged in several layers the troposphere extending from the surface to about 40 miles up the mesosphere stretching from the top of the troposphere to about 56 miles high and the thermosphere which reaches up to 125 miles above the planet's surface above this there's a transitional region called the exosphere that merges with the void of space the high concentration of carbon dioxide in Venus's atmosphere creates a strong greenhouse effect trapping heat and making it the hottest planet in the solar system even hotter than Mercury which is closer to the sun the greenhouse gases in the atmosphere absorb heat energy radiated from the sun preventing it from escaping back into space this results in surface temperatures averaging around 467 degrees Celsius which is hot enough to melt lead there's very little temperature variation between day and night or between the equator and the poles due to the thick atmospheres efficient heat distribution this results in a virtually constant furnace like temperature all over the planet's surface the atmospheric pressure on Venus is enormous approximately 92 times greater than Earth's sea level this is equivalent to the pressure experience 0 point 62 miles deep in Earth's oceans a human exposed to such pressure without Protection would be crushed despite this high up in Venus's atmosphere approximately 31 miles above the surface the pressure and temperature conditions are similar to those on earth surface Venus's atmosphere is perpetually cloaked in thick opaque clouds that cover the entire planet these clouds reflect about 75% of the sunlight that reaches Venus back into space which is why Venus is so bright and easily visible from earth the winds in Venus's upper atmosphere are incredibly fast reaching speeds up to 450 miles per hour much faster than the strongest Hurricane winds on earth these winds move in a phenomenon known as super rotation where the atmosphere rotates much faster than the planet's surface near the surface however wines are much slower typically less than a few miles per hour Venus boasts the highest mountain in the solar system Maxwell Montes rising 20 kilometers about 12 miles above Venus's mean surface level the planet's surface is also marked by numerous impact craters extensive lava flows and unique surface features like Corona circular structures caused by the upwelling of hot material from the mantle and arachnoids circular structures with a complex pattern of fractures due to Venus's slow rotation and dense atmosphere the planet doesn't experience significant seismic activity like earth however recent studies suggest that Venus may still be geologically active Venus has been a target of interest since the dawn of space exploration The Soviet Union's Venera and Vega missions NASA's Pioneer Venus and the European Space Agency's Venus Express have all contributed significantly to our understanding of the planet the Venera program achieved many firsts including the first human made device to enter the atmosphere of another planet and the first successful landing on another planet these missions provided valuable data on Venus's atmosphere and surface more recently NASA's Magellan Orbiter mapped almost the entire surface of Venus using radar to penetrate the thick cloud cover this mission reveal details about Venus's surface features and geology despite the challenges posed by Venus's harsh conditions scientists are interested in further exploring the planet NASA's planned Veritas and Davinci plus missions aim to study Venus's geologic history and atmospheric conditions providing insights into whether Venus might have once harboured liquid water or even life meanwhile the European Space Agencies Envision mission will focus on understanding why Venus in earth took such different evolutionary paths Japan's Akatsuki mission is currently studying Venus's atmosphere and weather patterns Venus our neighboring planet is an intriguing world of extremes its harsh environment poses significant challenges to exploration yet its similarity to earth in size and composition along with hints of potential past water and geologic activity keep our curiosity alive as we prepare for new missions to Venus we stand on the brink of major discoveries that could reshape our understanding of the solar system and our place in it as a reflection on our own planet's potential future Venus serves as both a warning and an opportunity for scientific discovery our solar system is a harsh environment volcanoes are destructive everywhere from the ice volcanoes of Saturn's moon and celidas to the immense lava fields of Jupiter's moon I o to our own planet earth it is truly true that we would not be here if there were no volcanoes volcanoes influence and alter our climate volcanoes are both the creators and destroyers of existence today's spacecraft and observatories have revealed volcanoes on planets we once believed to be dead the discovery of volcanoes on an object smaller than the moon was a major surprise if there are volcanoes on other worlds could there also be life volcanoes are among the most potent natural occurrences on earth they create new land destroy the old they emit gases that alter the atmosphere we breathe deep in our oceans volcanic heat fuels bizarre new forms of life volcanoes help sustain life on earth now we look for signs of life on other planets we understand that life requires water we are aware that it requires energy and this is where volcanoes come in as they generate tremendous quantities of energy if we locate volcanoes on other planets we may discover life the search begins with this planet which orbits the earth closest Venus a planet that closely resembles our own Venus and earth have similar masses earth and Venus were very similar 3 billion years ago with new land new oceans and an atmosphere both planets was conducive to life on Venus however something went awry something caused the history of Venus to diverge drastically from that of earth Venus took a definite turn to the dark side a long time ago Venus is hell our malevolent twin planet today the surface of Venus is like a furnace the surface is 900 degrees Fahrenheit hot it is actually heated enough to melt some metals so you have no chance Venus is a greenhouse world its atmosphere contains a high concentration of carbon dioxide it absorbs solar heat like a blanket actual images of Venus's surface reveal a desolate extremely hot desolation the planet was annihilated by dense CO2 atmosphere the CO2 was produced by volcanoes spacecraft in orbit provided the initial clues radar broke through Venus's thick clouds and showed volcanic formations all over the planet these formations look a lot like the shield volcanoes on earth round and flat shield volcanoes derive their name from their shape these volcanoes ooze but they ooze for thousands of years once we were able to map the entire surface of Venus using cloud penetrating radar we began to examine its landforms and discovered that many of them were quite familiar in particular we observed enormous shield volcanoes that resembled the shield volcanoes in Hawaii the radar images of Venus were identical to those of Hawaii's shield volcanoes in the past Venus was home to volcanoes we were astounded to see a picture of Venus for the first time we discovered a cratered volcanic surface there are at least 1,000 large volcanoes and possibly tens or hundreds of thousands of lesser ones lava planes cover three quarters of Venus's surface evidence of an ancient catastrophe this could have been a home for life it was instead consumed by flames numerous trillions of tons of carbon dioxide were expelled by Venus's volcanoes into the planet's atmosphere the temperature rose dramatically the oceans evaporated on earth carbon dioxide is able to absorb into the rocks it can be absorbed by the ocean on Venus however there is no water and the temperature is so high that carbon dioxide cannot even combine with the minerals volcanoes released carbon dioxide into the atmosphere eons ago and as time passed fewer and fewer methods existed to remove it from the atmosphere volcanoes sanitized the entire planet if Venus ever supported life earth is the only known planet with life that may alter this is the gas giant Jupiter with its moons believed to be frozen and lifeless a mystery surfaces as a cloud hovering over a cold and lifeless world upon closer inspection on Venus volcanoes transformed a planet similar to earth into a hyperheated inferno volcanoes on a planet similar to earth we're not a surprise but the discovery of volcanoes on the moon was an astonishment in March 1979 the Voyager 1 spacecraft provided us with our first up close look at Jupiter's miniscule moon Io a world we once believed to be frozen and lifeless and they witnessed something odd they observe this arc next to the moon and it almost appeared as though there was a second moon behind it we scratched our minds and asked what could that be everyone is aware that Io is lifeless dull and uninteresting and then people realized oh my god it's a volcanic eruption we discovered that the area is engulfed in volcanoes it is geologically extremely active there are constant volcanic eruptions and what they're erupting is a great deal of sulfur which becomes extremely heated and sulfur changes color as its temperature changes it may be red orange yellow or even black as a result these images of Io's visage resemble a pizza with various types of cheese and olives where the small black spots are Io is not dead it is alive and growing there are more than 400 active volcanoes the largest pali erupts from a gigantic lava lake it extends approximately 400 km into space it would be an extraordinary site if we could stand on the edge of that lava lake and observe that plume shooting off into the void of space Penny's eruptions are so massive due to iOS diminutive size there is nothing holding the lava back as there is virtually no atmosphere and little gravity these enormous eruptions make Earth's volcanoes resemble fireworks how can a moon so small be so volcanic the answer is Jupiter similar to how the moon raises the tides in earth oceans Jupiter raises solid rock tides on Io the orbit of Io around Jupiter is not circular sometimes it's closer sometimes farther away Jupiter exerts a gravitational force on Io Jupiter's gravity stretches and squeezes Io in every two day orbit the ground rises and falls by nearly 300 feet this pummeling generates extreme heat and enormous pressure wherever there are weak spots in the crust lava erupts volcanism is therefore planet scale in contrast to earth where certain portions are active around the plates or in weak areas this is an entire moon that's one active hotspot Io is the most volcanism active planet in the solar system as a result of the immense power of gravity volcanic activity on Io has taught us something new it taught us that internal energy sources can drive volcanism in a manner distinct from that on earth Io is a lava world that is extremely hot and violent it is difficult to conceive of anything surviving there we have discovered strange eruptions on numerous planets and moons but so far the only world where volcanoes are linked to life is ours or so we thought this is Europa it orbits Jupiter at a distance of nearly 500 million miles from the sun and is a 2,000 mile wide sphere of ice from afar its surface appears to be polished up close it's a different story Europa is pummeled by Jupiter's immense gravity just like its companion Io the surface rises and bends forming ridges and deep fissures when we first obtained close up images of Jupiter's moon Europa they seemed vaguely familiar and it turns out that they resemble Arctic ice flows and it turns out they are the same a global liquid ocean lies beneath Europas several mile thick icy crust magnetic measurements indicate Europas ocean is an astounding 60 miles deep the gravitational impact of Jupiter heating the rocky interior and melts the ice above as the core is stretched by tides and heated possibly melting it is not preposterous to believe that there is a boundary between a hot core and a liquid water ocean underwater eruptions on earth are surrounded by life the same may occur on Europa here the darkness is complete the pressure a crushing 2,000 Earth atmospheres a harsh environment but perhaps a cradle for life if there is evidence of life on earth why not Europa an energy source volcanic activity a universal solvent liquid water and a complex hydrocarbon chemistry are all present life would be difficult but not impossible on Europa there is life at every extreme on earth including searing heat crushing pressure and absolute darkness life on Europa may resemble our own in un anticipated ways if life exists beneath Europa's ice it would be aquatic but without eyes because there is no significant light organisms that essentially feed off the energy of the volcano would most likely utilize sonar to make sense of their surroundings volcanoes on Europa could be the Genesis of new life it is even conceivable that Europa is typical that this is the norm for planets with life earth may represent an exception consider that Europa could serve as a model for the billions of moons in the universe with liquid oceans so all of a sudden our horizons have expanded several billion times by looking at the moons of Jupiter our solar system is home to more than 170 moons multiply this by the size of the universe and that's a lot of potential habitats for life only liquid water and a source of energy are required potentially both are provided by volcanoes and they are ubiquitous this is Saturn twice as far from the sun as Jupiter however it also has volcanic moons and similar to Europa these moons could support life Saturn is one of the odd planets in our solar system with a 600,000 mile wide ring system and astounding 62 moons and one with a secret Enceladus is one of the lesser and more distant moons of Saturn and it's been known for a long time that it's covered in ice due to its extremely brilliant and reflective surface however when the Cassini spacecraft visited the planet it made a remarkable discovery not on the planet itself but on inside of this did the Cassini probe disclose a remarkable discovery a massive plume backlit by the sun and erupting into space is conclusive evidence of volcanic activity Cassini sensors zoom in on the south pole of the moon to capture these enormous craters scarring its surface at the south pole of Enceladus there are extraordinarily large fishers which open and close as Enceladus orbits Saturn due to the tides now these fishers are enormous they extend for hundreds of kilometers and when they begin to open you would see a large gravas opening at approximately 100 miles per hour along its length it'd be incredibly spectacular huge gravitational forces cause the surface to open and contract with incredible velocity this helps produce the heat necessary to dissolve ice and form oceans beneath the surface the conditions of the water beneath the surface of Anzeladus are ideal for life it is at the ideal temperature it would be beneficial for life liquid water would be just like seawater here on earth and the chemistry of the water we observe erupting from these fishers suggests that it contains salt it contains organic matter as well therefore we have identified a location in the solar system where there is a strong possibility that there is life right now in the ice particles Cassini has detected complex carbon molecules in conjunction with liquid water they suggest that perhaps life could exist deep within this mysterious moon and salad is possibly not alone another of Saturn's moons might also harbor life Titan one of the largest moons in our solar system the only moon with a thick atmosphere a frozen world ice as hard as rock lakes of liquid methane yet we may also discover evidence of volcanoes and the tatalising possibility of extraterrestrial life on this planet volcanoes are one of the most destructive forces in the universe as evidenced by iOS raging conflagration and Tritons ice and nitrogen explosions even on Saturn's enigmatic moon Titan however destruction can lead to the prospect of life it has a diameter of 3,000 miles making it larger than Mercury it has the thickest atmosphere of any moon in our solar system there is weather including cyclones winds rain and even lakes but the temperature is so low that liquid methane replaces water and it's loaded with essential compounds for life Titan has proven to be one of the most fascinating locations in the solar system it's an active world it is the only moon with a dense atmosphere an atmosphere very similar to that of earth due to the presence of nitrogen and as it turns out organic molecules high in Titans atmosphere methane gas reacts with sunlight to produce compounds essential to life but if sunlight consistently converts methane into organic compounds why does methane not run out methane is abundant in the atmosphere but we know that it is quickly eliminated by sunlight so it shouldn't be there there must exist a source of methane something on Titan emits methane in a continuous stream Cassini has spotted what appears to be a crater infrared cameras disclose that the crater is surrounded by various types of materials scientists believe the green areas may be volcanic possibly planes of lava ejected from Titans interior on Titan the boiling liquid emitted by volcanoes could be either ammonia or water methane and ethane are emitted by Titans volcanoes and this is likely the cause of the planet's extremely dense cloud cover and orange atmosphere this atmosphere likely originated from the outgassing of Titans volcanoes even on a globe as rigid is Titan volcanoes require heat on Titan there are two sources of heat radioactive substances heat the interior and Saturn's enormous gravity caresses the moon similar to Encyladas these two forces produce sufficient heat to transform ice into water and liquid methane into gas could volcanoes on Titan give life a chance to survive here the chemical reactions necessary for life as we know it require an atmosphere a solid surface liquid water and heat volcanoes could provide everything on Titan if life does exist on Titan it would be truly alien it would breathe hydrogen instead of oxygen and possibly swim through methane reservoirs at 300 degrees below zero there may be oceans of ethane possibly there are tidal pools as well as volcanic and hydrothermal activity perhaps volcanic heat could produce enough energy to support life on Titan that's a speculation but it can't be ruled out however we may not need to travel so far to discover signs of life we may discover it on Mars a volcanism rich world much closer to home volcanoes are ubiquitous throughout the solar system planets such as Io Titan and Triton are intricate volatile and violent once we believe that earth was the only planet with both volcanoes and life now we find volcanoes everywhere but alien life has yet to be discovered volcanoes exemplify the absolute force of creation and destruction they go hand in hand it is literally true that if there weren't volcanoes here we would not be here either volcanic cauldrons are the birthplace of life volcanoes create new landscapes see the atmosphere with complex chemicals replace the old with the new if volcanoes are linked to the processes of life where is life on other planets perhaps the origin of the answer lies in ancient times when the solar system was immature on a planet similar to our own this is the planet Mars Three billion years ago volcanoes were active the greatest volcano in the solar system still stands the cliffs leading up to it are greater than 6 miles in height even Mount Everest would be comfortable in their shadow this is the formidable Olympus Mong it covers an area the size of Arizona its crater alone is 53 miles wide a structure of this magnitude takes millions of years to construct a period of time that volcanoes on earth never have the Earth's crust is constantly in motion in the depths of the earth a solitary hotspot forces magma to the surface creating a new volcanic island while the hot point remains stationary the surface is in motion the new island moves away from the hot location and is replaced by a new volcanic island Mars is different the crust is locked solid on Mars there is simply no tectonic activity the crust is one big solid plate and so if there's a hotspot it just sits there and builds and builds and builds and you get a larger and bigger and bigger volcano therefore Olympus Mons is so enormous Today Olympus Mons is an icy remnant of a distant warmer era Olympus an extinct volcano on a fading planet is now a veritable colossus due to Mars's diminished atmosphere however the ancient volcanic terrain of Mars could one day support life the evidence is readily available on earth volcanoes on Hawaii have formed enigmatic tunnels known as lava tubes which are formed when rivers of molten rock rush into the ocean lava tunnels are formed when there is an underground river of a saltic lava magma and molten rock at 2,000 degrees Fahrenheit imagine it as an icy river with a crust of ice forming on the surface it's the same except here the crust is solid rock and the river continues to flow beneath creating this cave this lava conduit recent images imply that Mars volcanoes may have also created lava tubes any rocky planet with basaltic volcanism will likely contain lava pipelines now after possibly millions of years of inactivity these lava tunnels could revive life on the Red Planet this existence will be our own radiation will be one of the obstacles that future humans will face when attempting to live on Mars and especially during solar cyclones the incoming cosmic rays can be lethal the tunnels and caverns of Mars's extinct volcanoes could one day serve as an ideal home retaining air and shielding us from harmful radiation a long dead volcano could help fill a world with new light volcanoes are capable of both destruction and creation a supernova is the largest eruption ever observed by humans each detonation is the incredibly brilliant and incredibly powerful outburst of a star one variety of supernova is caused by a dying massive star's last effort this occurs when a star with at least five times the mass of the sun explodes with a tremendous explosion massive stars consume vast quantities of nuclear fuel in their centers or cores this generates enormous amounts of energy causing the center to become extremely heated pressure is produced by heat and the pressure produced by a star's nuclear combustion prevents the star from collapsing a star maintains equilibrium between two opposing forces gravity attempts to compress the star into the smallest most compact spheroid possible however the burning of nuclear fuel in the star's interior creates a significant outward pressure this outward thrust resists gravity's inward compression a enormous star cools down when it runs out of propellant this results in a decrease in pressure gravity triumphs and the star collapses abruptly imagine something with a mass one million times that of the earth disintegrating in 15 seconds the collapse occurs so rapidly that it generates immense shock waves that cause the stars outer region to erupt typically a dense nucleus and an expanding cloud of hot gas termed a nebula are left behind a supernova of a star greater than approximately 10 times the size of our sun may leave behind black holes the densest objects in the universe think about being an astronomer at the start of the 17th century as the telescope has not yet been developed you must use your limited vision to explore the universe then one day you see a truly spectacular scene in the next several weeks a new star will shine brighter than Venus very high levels of brightness make it visible throughout the daytime as the months pass it fades someone but persistently in the sky sky watchers across Europe the Middle East and Asia all witness the same thing that the German astronomer Johannes Kepler did in 16:04 now we know it was a supernova explosion a massive explosion that occurs when certain stars approach the end of their lifetimes and not a new star the latest supernova to occur within the Milky Way was in 16:04 maybe more nearby supernovas have occurred since then but they have been veiled by interstellar gas and dust and hints have not been noticed The Crab Nebula is an example of a remnant of a supernova that occurred thousands of years ago it's light reached earth around 1054 the supernova discovered in the Large Magellanic Cloud in 1987 was the closest thing to Kepler supernova in recent years in addition several supernove and other galaxies have been documented these may be seen with the naked eye but only with a telescope skywatchers in Kepler's day would have missed them totally hence it has been 418 years since we last witnessed a star explosion in our galaxy is a close brilliant supernova therefore long overdue scientists predict that between one and three stars should burst in our galaxy for century if the next supernova occurs modern astronomers will be better prepared for it than Kepler was or even scientists from only a few decades ago astronomers now have access to telescopes that can record visible light when used together these equipment will simulate the experience of flying near to a supernova and observing it with our own eyes in addition we have telescopes that are sensitive to infrared light or light with wavelengths that are beyond the red end of the visible spectrum infrared light with its longer wavelengths may penetrate gas and dust more easily than visible light allowing us to see objects that might otherwise be hidden from view with conventional telescopes examples of instruments that predominantly record in infrared include the James Webb Space Telescope the electromagnetic spectrum includes both visible and infrared light however neutrinos which are subatomic particles are also emitted by supernovas and modern detectors can capture them also astronomers now have detectors that can record gravitational waves which are tiny vibrations in the fabric of space time thought to be released by exploding stars in the scientific literature two kinds of supernova have been identified when a white dwarf star undergoes a type 1 supernova it sucks material off of a partner star until a runaway nuclear reaction occurs causing the white dwarf to be blown apart and send debris hurtling into space as a star runs out of nuclear fuel it collapses under its own gravity and bounces setting off an explosion known as a type 2 supernova there have been instances of both types of supernova being brighter than their host galaxy combined the tremendous amount of neutrinos that are released alongside the light makes type 2 supernovie very fascinating neutrino emission can actually begin before the explosion happens even though the field of neutrino research was in its infancy when the explosion of 1987 occurred three detectors were able to record a total of two dozen neutrinos one may expect hundreds if not thousands of neutrinos to be recorded by the global network of detectors should a supernova burst within our galaxy at this time very provocative signals might be produced in the event that a falling star forms a black hole therefore preventing the explosion from producing any further stellar debris in those conditions the neutrino stream would abruptly cease it would be awesome if you could see the black hole sharp boundary which indicates its formation the missing star might then be identified by comparing it to other stars in astronomical databases a lost star might be the site of a freshly generated black hole successful discovery of gravitational waves from a galactic explosion would round off the hat trick gravitational waves which Einstein said would exist when a huge body was accelerated or distortions in space time that are produced as the mass of the body accelerates such signals were identified for the first time in 2015 black hole and neutron star mergers are responsible for the gravitational waves seen so far yet when a supernova does occur in our galaxy it should also be seen computer models of supernova explosions have been used by astronomers for decades but many features remain unknown knowledge gained from studying gravitational wave data may shed light on the method what danger may a close supernova pose to life on earth in principle yes but the explosion would have to be quite close since there are currently no nearby stars in danger of exploding to be sure a close supernova's radiation outburst would be disastrous so this is excellent news the explosion would release harmful UVX and gamma radiation into space over a period of weeks damaging Earth's protecting ozone layer even if they didn't reach the ground without the ozone layer the sun's lethal UV radiation would flood the planet killing everything from phytoplankton in the oceans to humans it's possible that something like this occurred sometime in Earth's past around 360 million years ago near the close of the Devonian epic a massive extinction may have been caused by a supernova on the other hand supernova are not just destructive forces they may also give rise to new life astronomers and physicists point out that the nuclear processes that take place deep within exploding stars and spread throughout space as a result of the blast waves they create are the source of many of the heavy elements on which humans depend this means that a supernova would be the new gold standard for astronomers thanks for watching hope you enjoy it on a night in early September 1859 people all over America could see the Aurora it was blood red and so bright that when miners in the Rockies came out of their tunnels they thought the sun was coming up so bright in fact that even at midnight you could read a newspaper it didn't just happen in the US people all over the world saw these auroras no one knew why they had happened but earlier that same day an astronomer had seen something on the sun's surface that he called a white light flare back then the flare and the Aurora seem to have nothing to do with each other but we now know that the spectacular Aurora was caused by that flare which was a Corona mass ejection and if this violent event happens again it could destroy our modern technological world the sun is the most familiar thing in the sky it gives all life on earth heat and light it is so big that it's hard to imagine and it makes up 99% of the mass of the solar system this nearly perfect sphere has a diameter of 1.4 million kilometers and was made by the burning of hydrogen and helium for the last 5 billion years but from an astronomical point of view it's nothing special a G main sequence star also known as a yellow dwarf but looks don't always tell the whole story solar flares and explosions of plasma particles and radiation from its surface travel far into space we call this process the solar wind solar storms on the other hand are very violent eruptions and a Corona mass ejection or CME is the most dangerous because it has the potential to bring our high tech society to its knees today we'll find out how bad Acme could be and what astronomers are doing to keep an eye on our star to try to predict when they might happen step back in time to 1859 first in Victorian Britain it was okay for a gentleman to be interested in solar astronomy and one man did it in a very good way Carrington Richard Christopher we don't know what he looked like though because there are no known portraits of him Carrington Learned many important things from what he saw he saw that different latitudes rotated at slightly different speeds which meant the sun wasn't a solid body but a fluid one but he also saw that sun spots could be the start of a solar storm on Thursday September 1 1859 there were no clouds in the sky in the morning so Carrington was doing what he always did which was to look for sun spots he was using his telescope to project an image onto a screen at 11:18 he saw two brilliant beads of blinding white light appear in what Carrington calls a kind of conflagration stranger still they were gone after five minutes for no clear reason Carrington had seen a coronal mass ejection which was a huge magnetic explosion a huge cloud of charged particles that are thrown off the sun's surface after 18 hours the earth was hit by an electromagnetic storm people started calling it the Carrington Event at the time everyone was talking about the beautiful Aurora which could be seen all over the world even though a few telegraph systems went a little crazy because of power surges it didn't have much of an effect on everyday life don't forget though that this was 20 years before the light bulb was made that was in the past things would be very different right now Corona mass ejections are common but they can be different sizes and move in different directions so the question is what are the chances that something like what happened in Carrington will happen today and how would it change things so what is going on at the sun on the surface of the sun when we talk about the solar wind and space weather the sun is made of magnetic fluid and when that magnetic fluid rotates it twists and distorts the magnetic field a twisted magnetic field stores energy which can lead to eruptions which are called mass ejections and these explosions are huge sending out a billion tons of material at 1 million miles per hour so we wanna know where these things are going because if they move toward earth they could affect the technologies we use there's a very famous event in Quebec in 1989 where some power systems were disrupted for many hours in October we've heard about the Carrington Event which happened in the 1800s what would happen if it happened today and how would it affect us if we think about what we use satellites for now we have GPS spacecraft that help us find our way communication satellites weather satellites and even the stock markets are LinkedIn some way but we also have bigger power grids and a lot of wireless technology and we don't know how they will react how likely is it that something like the Carrington event could happen again we know that the sun can still make these things happen in 2012 there was an event that luckily didn't come toward earth but it did pass over one of the spacecraft we used to watch the solar wind and it pushed all the sensors on that spaceship to their limits so from what we've Learned we think that was at least as powerful as the Carrington event and maybe even more so it's just a coincidence that a big CME and one that's headed toward earth both happened at the same time and that's mostly just a matter of luck we either get one or we don't and how do we do with making predictions can we predict what the sun will do in a week a month or a year once Acme is up and running we can start making predictions so that we can figure out how big it is how fast it's moving and most importantly where it's going all of this sounds very scary space weather is a problem and the UK government knows this The National Risk Register lists it it's about as bad as a pandemic of flu so the people who make spacecraft are trying to find out what the most extreme conditions are in space so they can make them so that they can handle those conditions to a certain degree both NASA and ESA are getting ready to send satellites into space that will get closer to the sun than ever before The Met Offices Space Weather Operation Center opened in 2014 it is one of only three places in the world that can predict the sun's effects on earth around the clock so far the sun has had almost no sunspots and the side that faces earth is not expected to have any more sunspots or CMAs that are important so luckily there isn't much going on right now and things don't look too different in the long run so spacecraft satellites power supplies should be safe for the foreseeable future trouble is the foreseeable future in space weather forecast is at most just a few days we still don't know a lot about CME's like where they're going how big they are or when they might happen in the future two new solar probes will get closer to the sun than any other spacecraft has ever done The Parker Solar Probe was supposed to be sent into space and its destination will be close enough to the sun surface to fly through the source of the most energetic solar particles the Parker Solar Probe is an exploration mission that will measure the gas and magnetic field near the sun to figure out why this stuff is spreading out into the rest of the solar system and this the Solar Orbiter from ESA Solar Orbiter might find out how sunspots flares and coronal mass ejections on the sun's surface are related to the solar wind Solar Orbiter success will be very important for our understanding of how the sun works we think that the sun's magnetic field is made in a way similar to how earth is but it is much more dynamic and changes all the time we have an 11 years sunspot cycle during which the sun's magnetic fields move towards the poles and the polarity changes on top of that the magnetic field goes out into the solar system and flows over all of the planets Solar Orbiter will measure these magnetic fields for the first time and it will also give us the chance to watch the magnetic fields move to the Sun's poles to do this Solar Orbiter will take pictures of the sun's atmosphere and measure the number speed and temperature of the particles moving across the space between the sun and earth but the magnetometer which is made to measure the tiny magnetic fields in space that are carried by the solar wind could be one of the most important and sensitive instruments the sun is ever present in our lives it gives us light warmth and even life itself for Richard Carrington who was the first person to record Acme it was just a strange event but now we know that these things can do a lot of damage to the world we live in with new satellites and more observations we might be able to learn more about these events and predict when the next Corona mass ejection will happen the universe is full of strange and surreal paradoxes that challenge our understanding of the world around us from the mysteries of quantum mechanics to the mind bending properties of black holes the universe presents us with a plethora of phenomena that defy our intuition and challenge our perceptions of reality this video lets you see some of the many things we do not understand in the universe and the strange and surreal paradoxes in what we think we understand if you are interested in amazing videos about the universe be sure to subscribe to our channel to stay updated everything we know represents just 5% of the universe what is the rest normal matter protons neutrons and electrons make up just 5% of the universe staggeringly the other 95% is something which we cannot fathom see or understand we call it dark matter which makes up 27% of the universe and dark energy which makes up 68% but what are these mysterious components of our universe dark matter and dark energy are two mysterious concepts in astrophysics that scientists use to explain some of the strange observations that we make about the universe dark matter is a type of matter that does not interact with light or any other form of electromagnetic radiation this means that we cannot directly detect it using telescopes or other instruments that rely on light however scientists can infer its existence by observing its gravitational effects on visible matter such as stars and galaxy dark matter is thought to make up about 85% of the total matter in the universe but we still do not know what it is made of it does not behave like any of the known particles that make up ordinary matter such as protons and electrons some theories propose that dark matter consists of undiscovered particles that do not interact with light or other forms of radiation while others suggest that it may be made up of exotic objects such as black holes dark energy on the other hand is a hypothetical form of energy that is thought to permeate all of space and is responsible for the accelerating expansion of the universe unlike dark matter which has a gravitational effect that slows down the expansion of the universe dark energy has a repulsive effect that causes the expansion to speed up the exact nature of dark energy is not well understood but it is thought to be a property of space itself rather than a type of matter or energy that we can directly observe scientists believe that dark energy makes up about 68% of the total energy in the universe how many dimensions does the universe have to the best of our knowledge the universe as we know it has three special dimensions length width and height and one dimension of time making a total of four dimensions in space time this is known as the four dimensional space time however some theories in physics such as string theory propose that there may be more than four dimensions possibly up to 11 dimensions but these extra dimensions are thought to be curled up or compactified to too small to be observed at our scale this means that although they may exist they are not directly observable and their effects on the four dimensional space time can only be inferred through their influence on the physical phenomena that we can observe these additional dimensions would help us unify the mathematical bases of the four fundamental forces of nature the strong nuclear force the weak nuclear force the electromagnetic force and gravity do these higher dimensions exist and if they do is there a way for us to measure their presence or will we forever be trapped in our four dimensional world what if our universe is just one of a multitude out there the idea that our universe is just one of many universes known as the multiverse theory is a popular concept in modern cosmology and physics according to this theory there may be many other universes existing alongside our own each with its own unique properties and laws of physics if this is the case it would have profound implications for our understanding of the universe and our place in it for example it could help explain why our universe appears to be finely tuned to support life known as the anthropic principle if there are countless other universes with different physical laws and properties it would increase the chances of at least one of them being able to support life the multiverse theory also raises questions about the nature of reality and how we define what is real if there are many different universes with different physical laws are they all equally real or is our universe the only real one what is time time is one of the most difficult properties of our universe to understand researchers say that time is a measurable period a continuum that lacks spatial dimensions there seems to be an obvious direction or flow of time and it seems we can't travel backwards in time why is this are we trapped in the arrow of time perpetually moving forwards is the passing of time intertwined with the way our universe works according to the theory of Big Bang time itself began together with the rest of the universe about 13.8 billion years ago does that mean that it makes no sense to ask what was there before time is a fundamental concept in physics and is often defined as the progression of events from the past through the present and into the future it is a fundamental dimension in which events occur and is often represented as a continuous line or axis in the context of physics time is typically measured in units such as seconds minutes hours and year it is also an essential component of the space time continuum which is the four dimensional fabric of the universe consisting of three special dimensions and one temporal dimension the flow of time is often described as being any directional meaning that it moves forward and cannot be reversed this is known as the arrow of time and is often associated with the second law of thermodynamics which states that entropy the measure of disorder or randomness in a closed system tends to increase over time the nature of time is still a topic of ongoing research and debate in physics and philosophy some theories propose that time is an emergent property that arises from the complex interactions of the universe's fundamental components while others suggest that time is a fundamental property of the universe akin to space and matter particles violating the laws of nature in certain situations two particles can seemingly be an instant connection with each other even if they are located at opposite ends of the universe the phenomenon is known as quantum entanglement where two particles can become correlated in such a way that the state of one particle is instantly correlated with the state of the other regardless of the distance between them while this may seem like a violation of the laws of nature it is actually consistent with the principles of quantum mechanics however it is important to know that this does not allow for faster than light communication or the violation of causality this is because while the state of the entangled particles may be instantaneously correlated there is no way to control or manipulate this correlation to transmit information faster than the speed of light in fact there is a fundamental principle in quantum mechanics known as the no communication theorem which states that it is impossible to use entanglement to transmit information faster than the speed of light so while quantum entanglement may seem like a strange and mysterious phenomenon it does not allow for the violation of the laws of nature or the principles of causality could this feature of quantum mechanics one day allow us to send information instantaneously over large distances are we alone in the universe there are at least 2 trillion galaxies in the observable universe with more stars and planets in them than all the grains of sand on planet earth so where is everyone why haven't we encountered life from elsewhere is life incredibly rare or does it have a limited lifetime destroying itself before it is had the chance to seek out other life forms what does this tell us about the future of humankind the question of whether or not we are alone in the universe is one of the most intriguing and profound questions we can ask given the vast size and age of the universe it seems unlikely that earth is the only planet with the conditions necessary for life to emerge there are likely billions of potentially habitable planets in our galaxy alone however the fact that we have not yet encountered any definitive evidence of extraterrestrial life is known as the firm eye paradox there are many potential explanations for the furry paradox including the possibility that life is indeed rare but it is difficult for life to evolve beyond a certain point or that intelligent civilizations have a limited lifespan and self destruct before they can explore the galaxy it is also possible that we simply have not looked in the right places yet our current methods of searching for extraterrestrial life are still relatively limited and it is possible that more advanced techniques in the future could uncover evidence of life elsewhere in the universe does the self reference problem distort our perception of the universe we humans are also part of the universe we inhabit so when we look out to study the stars and galaxies are we really neutral observers of the universe when we explore the universe we are both observers and the subject of observation how can we pretend to be neutral when we are deeply embedded in what we explore could it be that this self reference problem affects the way we look at the universe and gives us an overwhelmingly wrong impression the self reference problem is indeed a complex issue when it comes to our study and perception of the universe we are not neutral observers of the universe but rather we are embedded within it this self reference problem can lead to potential distortions in our perception of the universe as we may unwittingly project our own preconceptions and assumptions onto our observations for example we may tend to focus on phenomena that we find particularly interesting or relevant to our own existence rather than taking a more objective and comprehensive approach by acknowledging our own biases and limitations we can work to develop more rigorous and objective methods of observation and analysis why is the universe seemingly so perfect for us the universe seems to be perfectly made for us but why is this why do the fundamental Constance of our universe such as the speed of light have the values that they do allowing life to exist could it be that there are infinite universes with infinite possibilities and we merely happen to live in one that is perfect for life there are a few possible explanations for this apparent fine tuning of the universe one possibility is the anthropic principle which states that the universe is the way it is because it must be compatible with the existence of observer in other words the universe appears fine tune for us because if it were not we would not be here to observe it this is sometimes referred to as the selection effect why is it easier to destroy something than to put it back together entropy is the amount of disorder chaos or randomness in a system one can never reduce entropy everything in the universe slowly moves towards disorder it's very easy to smash a window but impossible to put it back together exactly as it was before the principle of entropy moves the universe from structure to chaos from an ordered state to disorder what does this tell us about the fate of the universe as the universe continues to expand it will eventually reach a state of maximum entropy where all matter is uniformly distributed and there is no energy gradient available to drive further processes this state is known as the heat death of the universe where the universe will be cold dark and lifeless the universe is not a closed system as it receives energy from stars and other sources but the overall trend is towards increasing disorder and chaos however it is important to note that this process will occur over an extremely long time scale likely trillions of years in the future can anything escape a black hole we have observed the effects of black holes and we have seen one directly the gravitational force of these massive objects pulls everything towards them even light itself what happens in the mysterious infinitely dense center of a black hole could there exist such things as white holes the opposites of black holes that spew matter and time into our universe according to our current understanding of physics nothing can escape a black hole once it is past the event horizon which is the point of no return the gravitational pull of a black hole is so strong that it warps space in time and anything that crosses the event horizon is inevitably pulled towards the singularity at the center of the black hole where the laws of physics as we know them break down we do not know what happens at the center of a black hole as our current understanding of physics is unable to describe the conditions there it is commonly believed that the matter at the singularity is infinitely dense and compressed to a point of zero volume known as a singularity as for the possibility of white holes which are hypothetical objects that are the opposite of black holes there is currently no direct evidence to suggest that they exist white holes are hypothetical objects that are believed to exist at the other end of a hypothetical wormhole which is a hypothetical tunnel like connection between two points in spacetime however there is no direct evidence to suggest that wormholes exist either the universe is full of strange and surreal paradoxes our quest for understanding these is only just beginning as we continue to push the boundaries of our knowledge and explore the furthest reaches of space and time we can be sure that the universe will continue to surprise and challenge us in new and unexpected ways spurring us onto new and unexpected ways spurring us onto new hates of discovery and understanding we used to only know about the planets that circled around our sun but now we know that there are rocky worlds and huge gas clouds that circle other stars they have a great story to tell the early history of these planets would have been very very violent planets are made the same way everywhere they come from the dust and other things that are left over after stars are born so if they're all made the same way what makes them so different as it turns out the universe is full of galaxies gas clouds stars and planets there are eight worlds in our sun system but now we know that they are just a small part of the huge family of planets in the sky it's a very important moment in the history of science to be sure that there are other systems of planets out there and in our Milky Way galaxy which has 200 billion stars there are probably dozens of planets NASA sent the Kepler space telescope out into space in 2009 on a six year mission to find new planets that orbit other stars so far they found more than 400 some are huge spinning balls of gas that are five times as big as Jupiter others are huge rocky worlds many times larger than earth some follow wild erratic orbits so close to a star they're burning up one thing is clear no two planets are the same each one is unique but most of these new worlds are very far away and hard to study most of what we know about how planets work comes from the 8th circle our sun our own planets come in two main types there are four rocky planets in the inner solar system Mercury Venus Earth and Mars and in the outer solar system there are four giant gas planets Jupiter Saturn Uranus and Neptune each of the eight worlds is very different from the other seven when our solar system was born 4.6 billion years ago they started to develop their own personalities when the sun ignited it released a massive cloud of gas and dust into space all eight planets including the metal planets closer to the sun and the gas planets farther away came from this cloud of space debris all of the worlds in our solar system are made of the same materials they're made from the same cloud of gas and dust but they formed under very different conditions some of them formed close to the sun where it was much hotter and some formed far away where it was much colder and since the situations were so different the things that came out of them were also different so at the beginning of the solar system there was a pretty even mix of silicates water vapor hydrogen a lot of hydrogen methane and otherthane these elements in the dust cloud are like ingredients in a cake they cook in different ways based on how the ingredients are mixed and how hot the oven is and you mix the ingredients just like you did with the cake then you put it in the oven and bake it and it would change so basically this is what happened in the solar system overall the planet cooks in a slightly different way depending on how close it is to the sun near the sun where it is hot gases are burned off and water boiled away only materials that stay solid at high temperatures like metals and rocks can survive this is why only rocky planets form close to the sun as a planet moves farther away from the sun it cooks in a different way but what kind of planets will form depends on what's in the cloud based on what kind of cloud a solar system forms in it might not have any rocky planet because it didn't have enough materials to make something like earth instead it might have more gas giants and none at all if you want planets that are made of rock you need a cloud full of metals and rocks the next step is to turn down the heat as it cools some of the things in it that have a high boiling point start to condense out as solids and these very small mineral grains can start to form these tiny pieces of rock and minerals are the beginnings of a new rocky world they start to stick together over time if you had one dust molecule and another dust molecule and they would basically hit each other and make one slightly bigger dust molecule and they'd keep getting more and more this process is called accretion as these things got bigger they became basically rocks then rocks slam into other rocks and form boulders boulders smash together to form bigger boulders at some point you'll have something big enough that its weight is strong enough to start pulling things towards it so instead of just crashing into things and getting bigger that way it was actively pulling things in at first there were a lot of young planets in our own solar system maybe 100 most of them didn't make it if you go to the asteroid belt and look at the asteroid forvesta you can get a good idea of how big a hard planet has to be before it can pull itself into a sphere shape Vesta is only 329 miles across which isn't quite big enough to be a sphere to become round a growing planet needs to be 500 miles across then it has enough gravity to crush it into a sphere any smaller and it stays in irregular shape every time around Baby Planet crashes into something it makes it hotter and hotter until it starts to melt gravity is now starting to sort the heavy things from the lighter ones lighter things tend to float up and form a crusty layer while heavy things like most metals fall down and form a much denser core at the planet center finally the young planets are starting to look like planets but now they have to make it through a time of violence and destruction a cruel time that will decide which planets will live and which will die after the sun was made all eight of our planets came from the same cloud of dust and gas but they turned out to be very different there was no real plan for how each of the new planets should be made they did follow the rules of physics and chemistry but most of what happened was just a matter of luck About 4.5 billion years ago our son was surrounded by about 100 young planets it turned into a demolition Derby planet hit planet most were wiped out the early history of these planets would have been very very violent with many of these collisions happening in the last stages of each planet's growth as these collisions happened and things ran into each other some of the planetusimals started to grow at the expense of the others and these things that would eventually become planets grew and grew as they got bigger they sucked up all the smaller planet testimals around them which caused a lot of space to breathe to hit the surface of the proto planet after it was over there were only four different rocky planets left because of the things that happened to each planet in the past they are all so different from each other Mars is a frozen wasteland earth flows with liquid water Venus is a place full of volcanoes and Mercury is small empty and very hot because of a huge crash Mercury for example has a very thin crust and is very dense so it could have been a bigger planet in the past then something hit it at an angle which tore off the lighter crust and left only the dense center also hit hard was the young earth at the end of the earth development it was hit by something else which tore apart its mantle and sent the pieces into orbit around the earth where they re gathered to form the moon something also seems to have crashed into Mars the crust of the earth is thinner in the north than in the south one idea about what might have caused this is that the northern hemisphere of Mars was hit by something early in the planet's history which blew off a lot of its crust and that crust started to build up again in the south of Mars there were two effects of all these collisions they cut down on the number of baby planets that were still alive and they brought more ingredients to the survivors if you had a collision with something that was metal rich those chunks would tend to descend down into what was becoming the core where if you collided with something light or icy they would tend to just float about and form part of the crust instead near the sun there were four rocky planets that were almost done they were made of a solid core of hot iron surrounded by a layer of liquid iron and a shell of molten rock on top of that is a crust on the surface all of these rocky planets were made the same way from the same basic materials but each of them was very different different sizes and very different destiny space may look empty but it's not it's full of stuff blown out of the sun strong magnetic fields are made by the sun these fields rise up in giant loops above the surface when they hit each other a storm of very hot very charged particles shoots out into space the name for it is the solar wind astronauts can see it from space but only when they close their eyes when you close your eyes you sometimes see a little flash and that flash of light is caused by an energetic particle going through your head and interacting with the fluid in your eye and you see one of these every few minutes solar wind could kill the astronauts if they were exposed to a lot more of it during the Apollo program there was an explosion on the sun between two moon missions that would have killed the astronauts if they were there so radiation in space is a big deal but here on earth the solar wind doesn't pose much of a threat because we are protected by an invisible magnetic field that comes from the center of the earth you can make magnetic fields from motion by converting the energy of the motion into magnetic energy deep inside the earth the same thing happens as the earth spins the hot liquid metal flows around the solid core turning its energy into a magnetic field that comes out of the poles it keeps the solar wind from getting into the atmosphere of the planet and if the planet has a magnetic field the magnetic field will send the solar wind around the planet the solar wind is pushed away from earth by the magnetic field which protects the atmosphere and everything on the surface big storms of solar radiation can sometimes mix up the magnetic field then big light shows called auroras happen over the poles without a magnetic force field Earth's atmosphere and water would be blown away by the solar wind leaving a planet that is dead and dry a lot like Mars Mars was made the same way earth was but today it's cold and dry and there's not much going on so why have the two planets changed so much NASA sent two robots to Mars in 2004 to find out what was there the spirit and opportunity rovers looked at miles of the surface of Mars they proved that Mars is a dry dangerous desert with only one the atmosphere of earth but they did find signs that water used to be there Mars wasn't always a dry barren place we have found strong evidence that water was once below the surface rose to the surface and evaporated away in a few places we can also see ripples that are made when water flows over sand so not only was there water under the ground it had flowed across the surface if Mars used to have water it probably also had a lot of atmosphere around it so what happened we can see that there were volcanoes on Mars in the past so it had a hot interior at some point and because it was made of the same stuff as earth it would have had a hot iron core surrounded by liquid metal in the middle it should have also had a magnetic field the question is where did it go early in the planet's history Mars apparently had a strong magnetic feel and it was probably caused in the same way as it is on earth but Mars is a smaller planet than earth because of this it will lose heat more quickly and that means that a liquid core can become solid when it freezes if you completely freeze the core the convection will stop the flow stops and the magnetic field disappears as soon as the magnetic shield stopped working the solar wind blew away the atmosphere and the water evaporated Mars turned into a cold empty place the rocky planets Mars Earth Venus and Mercury all formed within 150 million miles of the sun but four times farther out the sun baked a very different kind of planet these monsters are very big made of gas and have no solid surfaces at all so far astronomers have found more than 400 new planets in solar systems far away almost every one of them is huge and made of gas our solar system has four of these so called gas giants Jupiter Saturn Uranus Neptune all of which have thick soupy atmospheres with lots of hydrogen helium and methane why are these outer four made of gas when the inner ones are rocky it's very cold here 500 million miles from the sun at the start of the solar system there was some dust but mostly gas and water frozen in ice grains it was cold enough to make solid snow where the big planets began to form and we think that we were able to make ice snowflakes and that these were able to stick together to form the cores of the giant planets we think that's why the big planets might have grown so big because there was so much ice and gas their cores grew to be about 10 times the size of earth a lot of gravity came from these big cores they had so much pull that they sucked in all the gas around them and made thick soupy atmospheres that went down tens of thousands of miles the more gravity they made the bigger they got more and more dust and debris kept getting pulled towards the planets and this is what made up their moons each of Jupiter and Saturn has more than 60 moons the gas planets have something else that makes them unique rings Saturn is different from the other planets because it has these beautiful rings it turns out that Jupiter Uranus and Neptune also have rings but they are very weak and hard to find but they are there there are rings around all four of the gas giants but Saturns are the most obvious from far away Saturns rings look like a single flat disc but in reality they are made up of thousands of small rings that are only a few miles wide each when the Casini probe flew by it found that billions of pieces of ice in space debris were moving around inside the rings at up to 50,000 miles per hour these pieces of ice and rock hit each other all the time some of them turn into small moons some of them fall apart but they never grow bigger because Saturn's huge gravity pulls them apart scientists are just now starting to figure out how the rings came to be the idea is that a comet hit a moon and knocked it out of its orbit bringing it closer to the planet Saturn's gravity tore it to pieces all of that stuff got stuck in rings that went around the planet but the real mysteries of the gas giants are deep inside them tens of thousands of miles below the clouds here is where things really get going it's a place so extreme that it goes against the natural laws most of the new planets we find orbiting far away stars are huge gas planets they are so big that Jupiter seems small next to them but nobody knows what happens inside gas giant planets whether they are in our solar system or far away we know that Jupiter's thick atmosphere goes down 40,000 miles and we can see bands of gas moving at high speeds that make violent storms on its surface but we don't know what's happening inside far below the storms NASA sent the Galileo spacecraft on a 14 year trip to Jupiter to find out December 7 1995 Galileo sent a probe into Jupiter's atmosphere which it did at a speed of 160,000 miles per hour as it fell through the thick air the parachute slowed it down it saw lightning in the clouds and 450 mile per hour winds the probe transmitted data back to earth for 58 minutes what happened to the Galileo probe that we dropped in it didn't hit anything it just kept falling into Jupiter's environment and the pressure kept going up and up and up as it fell it measured pressures 23 times higher than on earth and temperatures over 300 degrees higher than on earth when you're in the environment of a gas giant and you go deeper and deeper into this soup of hydrogen which has no solid surface it can still be very heavy and so eventually you would be crushed by the overlying weight of the material that's there even though the probe only went 124 miles down before it was crushed it showed scientists what Jupiters inside looked like but the dark heart of the planet still remains a mystery like some rocky planets the gas giants have a magnetic field too Jupiter's magnetic field is 20,000 times stronger than Earth's and so big that it goes all the way to Saturn which is more than 400 million miles away like on Earth Jupiter's magnetic field keeps the solar wind away from the atmosphere and keeps it safe when scientists looked at Jupiter's magnetic field they found that it affected the moons of Jupiter the volcanic moon Io orbits only 217,000 miles from the planet every second iOS volcanoes send a ton of gas and dust into space it gets even stronger because of Jupiter's magnetic field which makes powerful belts of radiation and this makes the area around Jupiter very busy in a lot of ways if you point a radio antenna at Jupiter you can hear how the planets and the magnetic field interact with each other Jupiter and Saturn can make auroras without the solar wind they make their own magnetic fields because they're so big these Aurora show that planets with gas also have magnetic fields but how do magnetic fields get made on gas planets on earth the job is done by a very hot liquid metal that spins around the planet's solid iron core most likely gas planets do about the same thing but gas planets don't have iron cores that get very hot they formed around frozen cores of dust and ice so we don't really know what's going on inside we really don't know what makes up the deepest parts of Jupiter's interior so it's possible that Jupiter has a solid core at its center or it could just still be liquid we might never know no probe could ever go the 44,000 miles to the center of the planet to look into it Galileo was destroyed before it could reach the center of the planet gravity and heat shape how planets evolve from their inner cores to their outer atmospheres they're the great creative forces in planet building but there's one more thing that has a big effect on how planets turn out and that ingredient is water planets may look like they are fixed and don't change but they are always changing one planet in our solar system lost its atmosphere and turned into a desert another planet got too hot and changed into the planet from hell Planet Earth has also changed and it was water that changed the game when you look at earth from space you can see a lot of water we are after all the blue planet that means it must be very wet right at first glance our world seems to have a lot of water after all three quarters of it is made up of oceans not true only point o six % of the mass of the earth is water some water is on the surface as oceans and some is stuck in the metal but actually the earth is a relatively dry rock all of the inner rocky planets formed very close to the sun so they started off dry any water they might have had either evaporated or was blown away when things hit these massive collisions that form the earth were so energetic that if there had been water here it would have evaporated and left the earth so where did all the new water on earth come from it's now here when you look at Jupiter Saturn Uranus and Neptune you can see that they have a lot of water locked up inside them and even more dramatically are the moons at least half of the water on the moons of Jupiter Saturn Uranus and Neptune a lot of water was out there so how did some of it get to planet earth and the answer is almost certainly that there were some asteroids and comets left in our solar system that were far enough from the sun that they could keep their water there were millions of these watery asteroids and comets that flew into the inner solar system some of them crashed into our planet over time the earth got the water that used to be in the asteroids this is what makes up the mass of water that now covers almost all of the earth without surface water there would have been no life what about water that is too much the oceans would be much deeper and cover the continents and even Mount Everest and it's likely that the exact amount of water that the earth has is what made it possible for us Homo sapiens to evolve into a technological species About 4 billion years ago a blizzard of comets and asteroids brought just the right amount of water to earth this is how the world we know today came to be and it's possible that the same thing is going on somewhere else in the universe right now there is a lot of water out there that much is certain the most common atom in the universe is hydrogen and oxygen is one of the next most common H2O will definitely be a very popular molecule which is exactly what is happening in our universe so water is everywhere in the universe and we're finding that planets are too but we haven't yet found another planet where water is liquid more than 400 new planets have been found by scientists our world doesn't look like any of them what we haven't found yet is a planet around another star that is about the same size mass and chemical makeup as earth so it remains an extraordinary holy grail for humanity to find other abodes that remind us of home but we'll keep looking we know that our galaxy alone has around 200 billion star and up to 40 billion of them could have their own planets we are entering what will be called the golden age of planetary exploration in the future we'll start to really understand for the first time how different things are out there I think this is going to be a very exciting time the laws of physics and chemistry tell us how planets are made many scientists think it's only a matter of time before we find another planet like earth one that formed from the same materials in the right place with the right amount of water one thing is certain there are billions of planets out there waiting to be discovered the search for life beyond earth is really just getting started but science has an encouraging early answer there are plenty of planets in the galaxy many with similarities to our own observations from the ground and from space have confirmed thousands of planets beyond our solar system our galaxy likely holds trillions but so far we have no evidence of life beyond earth is life in the cosmos easily begun and common place or is it incredibly rare here are a few theories about aliens extraterrestrial life exists this is the theory that life exists elsewhere in the universe perhaps even within our own solar system microbial life could potentially exist on Mars or some of the moons of Jupiter and Saturn for example more complex lifeform such as intelligent civilizations could also exist on planets orbiting other stars the Fermi Paradox the Fermi Paradox suggests that if intelligent life is common in the universe why haven't we detected any evidence of it some theories suggest that intelligent civilizations tend to self destruct while others propose that they are too far away or have no desire to communicate with us ancient aliens this theory suggests that aliens have visited earth in the past and have influenced human history and culture proponents of this theory point to ancient artwork and texts as evidence of alien visitation UFO sightings unidentified flying objects are often cited as evidence of alien visitation while many sightings can be explained by natural phenomena or human made objects some remain unexplained and could potentially be evidence of extraterrestrial visitation the simulation theory this theory proposes that our entire reality is a computer simulation created by an advanced civilization while not specifically about aliens this theory suggests that the creators of the simulation could potentially be an extraterrestrial civilization to start with let's address the most basic question do aliens exist well according to the Drake Equation which was developed in 1961 by astronomer Frank Drake the probability of intelligent life existing elsewhere in the universe is high the equation takes into account factors such as the number of stars in our galaxy the number of planets that could potentially support life and the probability of life forming on those planets using these factors the Drake equation estimates that there could be millions of intelligent civilizations in our galaxy alone but the question remains have we ever encountered these civilizations many people believe that we have and there are countless stories of alien sightings abductions and encounters however there is little concrete evidence to support these claims so let's explore some of the most popular theories about what aliens might look like the traditional image of aliens is small green big eyed beings is a product of popular culture however it is unlikely that aliens would look anything like this in fact it is impossible to predict what aliens might look like as their appearance would depend on the conditions of the planet they evolved on for example if an alien species evolved on a planet with high gravity they might have shorter stockier bodies if they evolved on a planet with a harsh radiation filled environment they might have evolved to be more resilient to radiation it's also possible that some alien species might not even have bodies as we know them they might exist as pure energy or as a hive mind collective but why would aliens visit earth there are a few possible reasons some scientists speculate that aliens might be interested in our planet because of its unique location in the universe earth is in a Goldilock zone it's not too hot not too cold and has the right conditions for life to thrive aliens might be interested in studying our planet to learn more about how life can survive in these conditions another reason aliens might visit earth is to make contact with us if there are millions of intelligent civilizations in the galaxy it's possible that some of them are trying to communicate with us however if this is the case they might be communicating in ways that we can't even comprehend their methods of communication might be vastly different from ours so what should we do if we ever do encounter aliens many scientists believe that we should approach any encounter with caution we should avoid making any sudden movements or aggressive actions as these might be misinterpreted by the aliens instead we should attempt to communicate in a peaceful and non threatening manner if we do make contact with aliens it could have profound implications for our understanding of the universe it could challenge our beliefs about our place in the cosmos and force us to confront some of the big questions about life the universe and everything now that we've explored some of the theories and possibilities of alien life let's consider the idea of the firm eye paradox this paradox asks the question if there are so many intelligent civilizations out there why haven't we seen any evidence of them why haven't we detected any signals or observed any spacecraft from other worlds one possibility is that advanced civilizations tend to self destruct with technology comes the potential for destruction whether through environmental damage war or some other catastrophe it's possible that many intelligent civilizations reach a point where they are unable to sustain themselves and ultimately fail another possibility is that intelligent civilizations have no desire to make contact with us perhaps they are simply not interested in earth or in communicating with other species or perhaps they are too far away to detect our signals and we are too primitive to detect theirs regardless of the reasons the Fermi Paradox remains a mystery and a subject of much speculation but let's turn our attention to the possibility of life in our own solar system while we haven't found any evidence of intelligent life there are some promising signs that microbial life might exist on other planets or moons for example NASA's Mars rover has detected methane on the planet's surface which could be a sign of microbial life and scientists have found evidence of subsurface oceans on some of Jupiter and Saturn's moons which could potentially support life if we do find evidence of microbial life in our own solar system it would be a major discovery and could have significant implications for our understanding of life in the universe let's consider the potential implications of discovering intelligent life if we were to make contact with an alien civilization it could have profound impacts on our society and our understanding of the universe for one it could challenge our existing beliefs and world views we might need to reevaluate our ideas about our place in the cosmos our religious and philosophical beliefs and our understanding of the origins of life it could also raise questions about the ethics of interacting with other intelligence species and the responsibilities that come with such interactions another potential impact is on our technology and scientific progress if we were to encounter a more advanced civilization we could learn from their technology and knowledge potentially accelerating our own progress on the other hand it could also pose a threat if the aliens have hostile intentions towards us it's difficult to say for certain whether aliens if they exist would be dangerous to us we have no concrete evidence of intelligent extraterrestrial life and so any speculation about their intentions or behaviors is purely hypothetical some people argue that aliens could be dangerous if they are more technologically advanced than us and have the ability to conquer or destroy us others point out that any civilization advanced enough to travel through space would likely have a more sophisticated understanding of the universe and maybe more peaceful and cooperative it's also possible that aliens could be indifferent to us simply observing us from a distance without any intention to interact with us at all overall while it's fun to speculate about the potential dangers of alien life the truth is that we simply don't know enough to make any definitive conclusions about their intentions or behaviors the search for extraterrestrial life should be approached with an open mind at a healthy dose of curiosity rather than fear or paranoia regardless of the potential impacts the search for intelligent life continues we are constantly developing new technology and refining our techniques to search for signals and evidence of other civilizations and while the chances of finding intelligent life may be slim the pursuit of knowledge and discovery is a worthy endeavor in and of itself that's all for today's topic of aliens we hope you've enjoyed this discussion and learn something new if you have any questions or comments please leave them in the comment section below thanks for tuning in and we'll see you next time
