Incredible Facts About The Planets In Our Solar System | Zenith Compilation | Spark

foreign [Music] neighbor it's very cold and dry and its weak gravity only holds a thin atmosphere as probes started to visit the red planet we gained a more accurate view of the surface and scientists began to wonder Mars had once been much warmer it had rivers and in its early years might have sustained life a succession of new techniques have been deployed trying to unlock the secrets of the red planet and while our knowledge of the Martian geology its atmosphere and its weather has grown immensely each new Mission to Mars raises more questions than it answers we still don't know if Mars has at some time been a home to life [Music] [Music] in 1877 astronomer Giovanni chaparelli made what he thought was the most accurate map of Mars yet drawn on it he showed canals in the early 20th century American astronomer Percival Lowell was convinced the canals were signs of a civilization existing on the red planet so began the search for Life on Mars in 1962 the Soviet Union sent the first probe the Mars M1 on a flyby Mission it was an audacious project and it failed the first of many failures by both the Soviet Union and the United States Cold War rivalry provided the motivation for these early missions in 1971 NASA sent Mariner 9 to Mars was the first probe to orbit another planet but scientists discovered that Mars was enveloped in a planetary dust storm on-orbit photography revealed little more than a Red Cloud foreign ER 9 was joined by two Soviet orbiters both equipped with Landers [Music] the Mars 2 Lander crashed but the Mars Freelander made it to the surface intact it returned one garbled image and then stopped functioning Mars now had three orbiting spacecraft all looking at a Dusty featureless planet the two Soviet probes were identical but the American probe had one key design difference while the Soviet orbiters began photographing the planet following predetermined schedules NASA were able to command Mariner 9 to wait in hope that the dust would eventually settle it took months for the atmosphere to clear but when it did Mariner 9 saw three craters protruding above the Dust they were the tops of giant volcanoes on what was called the fasis plateau soon more complex geological features began to emerge in places the surface was cratered suggesting the tectonic forces that constantly renew the Earth's surface were absent on Mars volcanic activity that built the Solar System's largest volcanoes had stopped billions of years ago this enabled NASA scientists to compile an accurate global map of Mars and to decide upon Landing sites for the Viking probes that followed in 1976 foreign and two were identical orbiters with Landers that both made successful Landings on the surface both returned pictures of the Martian landscape the primary objective of the Viking program was to find signatures of life but researchers now feel the three experiments tasked with carrying out the analysis had limitations as researchers on Earth began looking for traces of life in extreme environments they began to rethink where Life on Mars might survive yet the consensus at the time was that Mars was sterile and the idea of Life on Mars died [Music] after a 20-year Hiatus in Mars research Mars Global surveyor went into orbit in 1996. [Music] the pictures it relayed back were clearer than anything yet seen from the red planet although most Mars orbiters had been tasked with mapping the planet's surface this was different the high resolution images that the Mars Global surveyor sent back revealed rivers and even river deltas but the occasional impact crater suggested that nothing has flowed in these systems for billions of years [Music] in July 1997 another probe arrived the Mars Pathfinder was one of a new breed of missions being pushed by NASA's new administrator Under The Guiding philosophy of faster better cheaper the idea was to cut development times cut budgets and although the risk of failure would rise the reduced price tag could mean more missions Pathfinder would land a small Rover on the surface to do this it used radically new airbag technology the technique Drew more from Automotive Safety Systems than from previous space missions The Landing site in Mars Northern Hemisphere known as Aris valis is one of the planet's rockiest areas yet it was thought to be a safe area to land the broad array of different rock types are believed to have been deposited during an ancient flood the new Landing technique worked perfectly and served as a proof of concept that would be used on future missions foreign ER consisted of a base station equipped with three solar panels that unfolded like pedals there were sensors to measure atmospheric pressure air temperature and wind speed as well as a transmitter to communicate with Earth in addition Pathfinder acted as a base station for the Sojourner Rover that explored the surrounding area Sergio was fitted with cameras and an alpha particle x-ray spectrometer it was the first mission to have its own website the Rover returned thousands of images and important detail about the atmosphere and geology and its popularity guaranteed more Mars missions [Music] on the morning of April the 7th 2001 another Mars Orbiter was launched Mars Odyssey was equipped with three primary instruments and it had the ability to act as a relay satellite between future service missions to the red planet and Earth on its arrival at Mars it used a new technique to go into orbit after firing a relatively brief pulse of its engine Mars Odyssey went into a highly elliptical orbit that at its closest approach had its skimming the planet's thin upper atmosphere called Arrow breaking this technique allowed the craft to circularize its orbit over a period of three months and it saved around 200 kilograms of fuel probe is still in operation today breaking all records as the longest serving Mars mission in December 2003 a new player arrived at Mars the European Space Agency using a Russian launcher had sent Mars express its first planetary Explorer it was equipped with a landowner known as beagle though all contact was lost with the Lander Mars Express continues to return valuable data the mission has been granted several extensions the latest till 2020. equipped with a high resolution stereo camera the probe returned unique 3D views of the planet's surface [Music] the Orbiter determined that the polar ice caps contain a blend of Frozen CO2 and Water Ice [Music] in the atmosphere Mars expressed detected first methane and then ammonia both gases deteriorate rapidly in sunlight so there must be sources on Mars continually producing them ethane and ammonia can rarely be made inorganically but they're generally associated with life one month after Mars Express went into orbit a NASA Lander arrived at Mars followed three weeks later by a second identical craft [Music] they were the Mars exploration Rovers called spirit and opportunity foreign Spirit the first to land was targeted at the gusev crater opportunity would land at the meridiani platinum on the opposite side of Mars though they were much heavier than their Pathfinder predecessor they used the same bounce Landing technique both Landings were successful and on target after the craft had righted itself it detached from the Lander and began autonomously unfolding its solar panels and Camera Mast while this was happening the team back at the jet propulsion laboratory waited signals confirming the Craft's safe arrival took 15 minutes to travel back to Earth [Music] many of these people had invested years of their lives in this project and the real Mission had only just commenced both Rovers were designed to operate for 90 Mars days a solar day on Mars is about 40 minutes longer than an Earth Day and to avoid confusion the science team operating The Rovers refer to a Martian day as a soul Mission designers knowing about the dust storms on Mars felt that the solar panels on the two Rovers would eventually be blocked with dirt and stop functioning but it became clear that the winds on Mars were clearing the panels soon NASA announced that opportunity had found evidence confirming liquid water had once flowed on Mars there were pictures from the meridiani planum of stratified patterns in the Rocks suggesting sedimentation the distribution of chlorine and bromine at the site were Clues to the areas passed as the shore of a Salty Sea in April 2004 NASA announced it would extend the Rover's missions from three to eight months [Music] it would be the first of many such Mission extensions [Music] The Rovers were equipped with an abrasion tool to grind away a portion of a rock's surface for a more detailed uncontaminated analysis of geological samples [Music] was first done by Spirit at a rock named Adirondack at gusev Crater it was a first in planetary geology researchers agonized before using the tool because of the drain it makes on the Rover's energy budget The Rock was made of Olivine pyroxine and magnetite making it very similar to volcanic basalt on Earth when Spirits right front wheel stopped working Engineers used a duplicate Rover to devise a reversing technique that enabled the Rover to drag its frozen wheel this left a Furrow behind in the soil which presented a new area of research for the science team white or yellow deposits seen within the furrow were various types of salts that only form in the presence of hot water on Earth hot water provides an environment in which microbes can thrive Spirit limped on for another three years before it became stuck in loose sand again the engineers began working with a replica which they placed in an identical situation where nothing was able to free the Rover it was declared a stationary research platform further attempts were made to position the Rover so its solar panels could operate more effectively but even this was not possible the last communication from Spirit was in March 2010 opportunity lasted until June 2018 when dust clogged its solar panels in March 2006 NASA's Mars reconnaissance Orbiter arrived at Mars and began the now routine business of Aero breaking though this procedure took roughly six months the saving and fuel will see the craft functioning at Mars into the 2030s one of the primary functions of the new Orbiter is as a Communications relay station it's three meter antenna transmitting in the ultra high frequency band enables very high data rates by November 2013 it had tripled the amount of data sent to Earth by all the other NASA missions combined [Music] foreign camera began revealing the surface of Mars in the finest detail these are active falling Dunes in East copperities chasma the polar region free of the seasonal dry ice again surrounded by Dunes the southern hemisphere pits in the residual cap of carbon dioxide [Music] the poles of Mars were now attracting Keen interest follow the water had become NASA's catch cry the Phoenix Lander was targeted at the northern polar region to follow up on information from Mars Odyssey suggesting frozen water lay beneath the surface near the poles [Music] because imaging had revealed the region to be unvarying a Rover was deemed unnecessary the Lander had been designed to use a parachute to decelerate with rocket thrusters to deliver the craft to the surface unlike NASA's previous three Rovers which had bounced this decision proved controversial as one strand of research suggested the rocket fuel would contaminate the very area that the Lander was tasked with analyzing the craft waited 15 minutes to allow any dust to settle before it deployed its solar panels Phoenix had landed during the early spring in Mars's Northern Hemisphere so the solar panels would receive plenty of light for the planned 90-day mission [Music] as well as its camera mask Phoenix was equipped with a meteorological station that recorded the daily weather it featured a wind indicator and pressure and temperature sensors in addition a vertically pointed lidar was able to observe cirrus clouds forming in the region and snow falling in the polar atmosphere [Music] these phenomena had not been observed before the Lander also had a robotic arm that could dig half a meter into the soil and deliver samples to the analyzer a combination of eight high temperature ovens and a mass spectrometer in one excavation the cameras recorded a white substance which gradually disappeared given the temperatures and the time it lasted It could only have been water ice that sublimated after it was exposed the soil was slightly alkaline and the presence of perchlorate which kills bacteria was not good news for those hoping for Martian life Phoenix operated for two months longer than planned before the Gathering winter completely shaded its solar panels [Music] while the planet still had Subterranean deposits of ice there was precious little left at the surface yet it was now understood that many of the red planet's features had been carved by running water samples analyzed from across the planet affirm that water and nothing else had made these changes to the Martian landscape [Music] Mars had once been more like Earth yet it had lost its surface water and most of its atmosphere and the question of life persisted could it have emerged in a warmer wetter past and could it still be present below the surface [Music] the next Mars mission would be NASA's most ambitious yet known as curiosity the car-sized Rover would be powered by a nuclear battery making it immune to the dust problems experienced by spirit and opportunity [Music] seven six curiosity was launched on an atlas 5 from Cape Canaveral in November 2011. why main engines start zero and liftoff in mid-2012 it entered the Martian atmosphere heading for Gale crater the jet propulsion laboratory monitored the entry closely but had no control over events in Mars's thin atmosphere the parachute could only slow the heavy craft to around 320 kilometers per hour nearing the surface the Rover descent stage dropped out of the AeroShell and Rockets kicked in at this stage radar was guiding the Lander to the surface and a small camera was recording images of the terrain below the Rover next curiosity was lowered on a tether Beneath The Descent stage this sky crane technique was used to avoid too much swirling dust exposing the Rover to unnecessary Danger everything had worked exactly as it was supposed to and the American Engineers were relieved talking The Landing had been the most precise ever before curiosity could start work its computer went through a checklist to make certain that all systems were operating correctly it was a day before the Rover deployed its camera Mast and Communications antennas it's thought that Gale crater is three and a half billion years old and that its sediments have been laid down first by water and then by wind NASA now has a sophisticated mobile science laboratory on Mars connected to Earth by the most advanced Communications link courtesy of the Mars reconnaissance Orbiter the Rover's primary objective is to discover if conditions suitable for life ever existed or still exist on Mars it's also Gathering detailed information about the current conditions on the red planet particularly the radiation levels that will have an impact on proposed manned missions thank you Curiosity has analyzed the dust from a number of holes it drilled revealing sulfur nitrogen hydrogen oxygen phosphorus and carbon all elements essential to life in its six years on the surface of Mars Curiosity has traveled around 20 kilometers but the driving is taking its toll it routinely sends back a series of self-portraits mainly for Diagnostic reasons its Wheels have taken severe damage which will undoubtedly lead to design changes for future Rovers its computers are also giving problems but a new suite of missions is slated to arrive at Mars in 2020 that will continue profiling the planet there is one aspect of the Martian environment that has never been investigated but that's about to be addressed the Mars Insight probe has been targeted at the flat Elysium planetia close to the equator to spend two years investigating the planet's interior it made a Flawless Landing in November 2018. after unfurling its solar array it spent weeks selecting a suitable spot to deploy a seismometer onto the surface to monitor Mars quakes it's clear that Mars had a warm wet past but it's cold and very dry now learning about the planet's geological activity will help us know why Mars has changed the inside probe also hammered a thermal sensor into the surface to gather data on heat flow from the planet's core by understanding processes within Mars we can learn how the geological histories of Mars and Earth began to diverge the ringed planet Saturn more than 100 times the mass of Earth its metallic core Lies Beneath 80 000 kilometers of liquid hydrogen and helium it's called a gas giant Saturn is orbited by at least 62 moons each unique some with complex and dynamic environments our only detailed examination of the saturnian system ended in 2017 when the Cassini probe was intentionally crashed into the planet's dense atmosphere to guard against accidental contamination of the moons [Music] [Music] thank you viewed from Earth Saturn's rings are visible but not in any detail they were thought to be solid until mathematical analysis suggested they were orbiting particles but how did they get there and why was Saturn alone in having rings in the early days of space research Saturn was just too far away conventional Rockets could only just reach Mars [Music] in 1964 NASA realized that a space probe launched in 1977 could take advantage of a rare alignment of the outer planets to fly past all the gas giants using gravitational assistance from the planets it would just be possible with the technology of the day an ambitious new Mission began to take shape it was dubbed The Grand Tour [Music] two probes that were far in advance of anything yet attempted would be part of the Mariner series [Applause] because no spacecraft had been sent Beyond Mars mission planners felt it would be wise to send two rudimentary Advance probes to Jupiter and Saturn to test the deep space environment researchers didn't know if it was even possible to cross the asteroid belt between Mars and Jupiter in 1972 Pioneer 10 was launched towards Jupiter and the following year a twin Pioneer 11 was sent to Saturn both craft passed by Jupiter and discovered that the electron radiation there was 10 000 times as strong as at Earth this was a surprise to engineers at Nasa who had to modify the more sophisticated craft they were preparing for The Grand Tour tomorrow the probes being built at NASA's jet propulsion laboratory were part of a program known as Mariner Jupiter Saturn but this was soon changed to the Voyager program [Music] they were launched 16 days apart in late 1977. while Pioneer 10 was heading toward Interstellar space and Pioneer 11 was still two years away from Saturn in 1979 as Pioneer 11 approached the ringed planet it began sending back pictures far clearer than anything seen before a new ring the F ring was observed for the first time the craft flew by Saturn passing beneath the Rings Mission planners were uncertain how broadly the ring particles spread if there was a threat to the spacecraft they were prepared to sacrifice Pioneer 11 to get a clear idea of the environment they would encounter with the following Voyager craft the probe passed the ring safely and continued Beyond Saturn into Interstellar space NASA received its last communication from the Probe on the 24th of November 1995. the following Voyager 1 and 2 probes were very robust designed to survive for a very long journey and with far greater technical capacity than the pioneers in late 1980 Voyager 1 approached Saturn although its high-resolution polarimeter had failed it was still able to see a new ring called the g-ring orbiting 100 000 kilometers above Saturn's Cloud tops for the first time researchers could see how the Rings moved uneven features within the Rings were called spokes they're transient and are thought to be particles lifted by an electrostatic charge [Music] after such a long preparation information was now coming into JPL at such a rapid rate that the planetary scientists were overwhelmed Saturn's moons were of great interest Voyager 1's path had been chosen because it would take it close to Titan the Solar System's second largest moon and the only one to hold an atmosphere but the images were disappointing because the thick atmosphere of methane and nitrogen was impenetrable Voyager 1 now looped up above the solar system on a trajectory that would take it to Interstellar space [Music] as it looked back at Saturn it captured one last image from a unique angle it was almost 10 months before Voyager 2 neared Saturn its different path meant that it could continue onto Uranus and then to Neptune its high definition camera was still working and planetary researchers were expecting detailed pictures of the Rings they were not disappointed the varying densities and spacing within the Rings was more complex than anyone had expected the Rings are named for letters of the alphabet in the order that they were discovered it became apparent that the Rings had changed in the time since Voyager 1 had seen them though they stretch from seven thousand to eighty thousand kilometers above Saturn's equator their thickness is on average just 30 meters the spacecraft also returned pictures of the moon Enceladus its cracked uncrated surface was made of ice below which is an ocean ultimately Voyager 2 left Saturn unable to go into orbit It sped on toward Uranus it would be 23 years before another probe visited and liftoff of the Cassini spacecraft to Saturn launched in 1997 Cassini was a collaboration between NASA the European space agency and the Italian space agency it would take more than six years to reach Saturn [Music] Cassini was the biggest most complex interplanetary spacecraft yet devised its 12 different instruments each had a dedicated team of research Specialists on Earth to interpret the data it sent back [Music] its High Gain antenna was used for high-speed data relay back to Earth but in what's called a ram maneuver it was sometimes used as a shield to protect the spacecraft from debris impact especially when crossing the plane of Saturn's rings on the 1st of July 2004 it fired its engine to go into orbit around Saturn it was designed not to fail beside its main engine was a backup in case the primary engine did fail it had 16 monopropellant thrusters eight prime and eight more also as backups [Music] control of the jet propulsal laboratory the engineers could not know what was going on the time delay and cassini's disappearance behind Saturn meant that much of the Telemetry was recorded for later replay back to Earth the engine burn lasted for 106 minutes Cassini was the first probe to employ a solid-state recorder unlike the earlier Voyager craft that registered data on a mechanical tape recorder cassini's first orbit followed a highly elliptical path that would take it out past the moon Titan this was important for two reasons its gravity would be necessary in modifying cassini's course so Saturn and its other moons could be observed from different perspectives secondly Titan with its dense atmosphere was targeted as an area of major interest for the Cassini team the European Space Agency had built a small craft called highgens attached to the side of Cassini on its second approach to Titan the Huygens probe was released it was equipped with a heat shield a parachute and enough battery power to last for several weeks [Music] over a 20-day period Huygens drifted for 4 million kilometers [Music] transmit data back to the orbiting Cassini which would later relay it to Earth three days after separation Cassini made a course correction that would prevent it colliding with Titan as highgens reached Titan's atmosphere Cassini was coming around for its third close approach of the Moon ready to receive signals from the Lander [Music] foreign sampled the atmosphere and recorded images of the landscape pictures from beneath the clouds revealed low Hills and channels cut by flowing liquid there were few impact craters and those that existed were heavily eroded was the first landing on a body in the outer solar system images from the surface showed weathered rocks made of Water Ice what surprised everybody was that Titan is a geologically active world where liquid ethane and methane rather than water have carved the features as Cassini continued looping out around Titan it used radar to map the moon's surface confirming the widespread distribution of hydrocarbon Lakes [Music] the probe discovered that rain fell on Titan but it was a mixture of liquid ethane and methane the moon has weather and other erosive forces similar to Earth but the chemistry is radically different interesting the small moon Enceladus Drew attention to itself as the whitest most reflective body in the solar system its surface shows cratering in the north but the South has giant cracks known as tiger stripes [Music] on cassini's first Loop passed Enceladus the magnetometer team noticed an odd deflection of Saturn's magnetic field as though the small Moon had an atmosphere during its second pass the team noticed the same phenomenon they asked for the next Traverse of Enceladus to pass much closer so cassini's cause was modified to fly just 175 kilometers above the icy Moon the probe passed through a plume of water vapor emanating from the tiger stripes it contained common salt in all Cassini made 24 swoops past Enceladus with the closest approach flying just 25 kilometers above the surface each one of the probe's instruments gathered different evidence about the Jets of water expelled through the cracks in the moon's South on Mars rovers have been combing the surface looking for traces of life but Enceladus was flaunting remarkable signs gravitational analysis revealed a liquid ocean beneath the ice and infrared detectors saw heat emanating from the cracks foreign as well as salt the science team discovered traces of silica that can only dissolve in hot water hydrogen and organic compounds were also detected we know from Cassini that encidis has a global ocean so you have water we also know that there are Organics coming out because they've been directly measured both in the gas and in the particles we also know there's a source of energy the South Pole was hotter than the rest of Enceladus and then we found evidence that deep inside their hydrothermal vents on the sea floor of Enceladus so these hydrothermal vents would Supply the Heat and the nutrients that could possibly support life with a diameter of 500 kilometers Enceladus is just too small to sustain a hot core via radioactive decay gravitational squeezing by Saturn explains some of the heating but the source of the high temperatures detected remains a mystery but not only is there liquid water underneath the surface but there's organic material there's a heat source and you know when when people get excited about the potential for life elsewhere in the solar system they're four things that you need you need a heat Source you need liquid water you need organic material and you need those three things to be stable over some period of time so that life could potentially form Enceladus we've got three we're not sure about the stability over time yet in the earth's deep oceans hydrothermal vents provide the warmth and nutrition to support life they may even have been important for the origins of life planetary biologists are speculating that the environment in the oceans of Enceladus may be the most likely place in the solar system to find some sort of extraterrestrial life it took a while for Cassini to be in a position where backlighting from the Sun allowed the Imaging team to capture pictures of the plumes using a similar technique the Imaging team took this picture with Saturn directly between Cassini and the Sun it reveals Saturn's e-ring the hazy outermost ring that is usually very difficult to see the e-ring is a result of the plumes from Enceladus and is constantly replenished by the salt water eruptions [Music] saying that Saturn has 62 moons is misleading particle within the ring system could be regarded as a moon there are the inner large moons and the outer large moons there are the Shepherds that shape the Rings there are co-orbitants that exchange orbits and there are even moons that orbit other moons all are unique during the Voyager missions interest in the moons came as something of an afterthought but for Cassini close examination of the moons was planned from the beginning iapetus orbit Saturn Beyond Titan it was first observed in 1671 by Giovanni Cassini he could see it as a DOT of light to the west of Saturn but could not see it when it should have been to the east [Music] iapetus has one bright face and one dark one because the Moon is tidally locked to Saturn it is always the dark face that leads as it orbits one Theory suggests that it sweeps up debris that spews from Phoebe a more distant Moon another feature of iapetus has scientists baffled a ridge along the Equator stretches more than halfway around the moon it's twice as high as Earth's tallest mountain with iapitose being just 1500 kilometers across the ridge gives iapitus the appearance of a walnut very accurately directed bursts from cassini's Main engine allowed Mission Engineers to modify the probe's looping orbits so Mission Specialists could focus on various moons different areas of the Ring system or different parts of Saturn itself with gravitational assistance from the moons particularly Titan Mission Control were able to conserve fuel the Cassini probe performed so well it received two Mission extensions but the fuel could not last forever planners had scheduled the most hazardous part of cassini's mission for its final year at Saturn late in 2016 Cassini began a series of polar orbits that would take it close to the outer edge of the Rings in what mission Specialists called grazing on the Rings the Craft's Mass spectrometer and its Cosmic dust analyzer would sample particles and gases as it crossed the ring plane in orbit 251 its first pass above Saturn's North Pole it recorded the peculiar hexagonal storm that was first hinted at by the Voyages the storm more than twice the diameter of Earth maintains its hexagonal shape but its color changed with the advance of Summer at its Center is a cyclone shown here in false color with red indicating lower cloud and green higher Cloud winds at its Edge blow at 540 kilometers per hour [Music] one part of cassini's dual technique magnetometer had stopped working early in the mission without it the craft had to do roll Maneuvers from time to time to calibrate the instrument the spacecraft would make 20 ring grazing orbits with the work of its instruments mapped out to the second [Music] as the sun was almost directly behind the Rings Cassini looked for dust clouds something is reducing ring particles to fine powder [Music] Cassini made a number of radio occultation observations with the Rings between the spacecraft and Earth three radio signals of differing wavelengths were transmitted simultaneously allowing the radio science team to build a profile of the Ring particles this false color image of the a-ring the outermost of the large bright Rings shows red for particles larger than five centimeters across green denotes particles smaller than five centimeters with blue for particles smaller than one centimeter the complex gravitational interaction between Saturn its rings and its moons leads to gaps in very particular places before Cassini arrived only 18 moons were known that number has grown to 62. Prometheus acts as a shepherding Moon limiting the inner edge of Saturn's effering along with Pandora which orbits outside the effering the two moons keep the ring narrowly confined [Music] in April 2017 cassini's orbit was changed for the Final Phase of its Mission the probe would now Loop inside the Rings [Music] though it would ultimately mean burning up in Saturn's atmosphere the information gathered from such close proximity to Saturn and its rings would give a fuller picture of the gas giant it was decided that intentionally destroying Cassini was preferable to letting it drift without fuel possibly contaminating one of the moons [Music] cassini's sensors began picking up a stream of ring particles raining down upon Saturn a continuous shower of ice and dust particles are dragged toward the planet's equator by gravity or at higher latitudes charged ring particles spiral in along magnetic field lines [Music] every second ten thousand kilograms of ring rain falls to the surface at this rate the Rings will be completely gone in 100 million years [Music] researchers were surprised to discover an electric current flowing between the inner d-ring and the upper atmosphere toward the end of cassini's close passes of Saturn the spacecraft began catching the upper edge of the atmosphere all information had been retrieved from the recorders data now was transmitted directly back to Earth but it relied on the spacecraft's thrusters to stop Cassini from tumbling keeping its High Gain antenna pointed accurately the probe's final work was sampling the atmosphere and measuring the offset of Saturn's magnetic axis [Music] Mission Control there was no more control the engineers could just monitor the signals sent from Saturn 84 minutes previously [Music] within the next 45 seconds so will be the spacecraft it will take years to process the data gained from Cassini as yet there are no future missions to Saturn scheduled thank you Jupiter is our Solar System's largest planet it's more than twice the mass of all the other planets combined its swirling atmosphere moves in bands at different latitudes and its Great Red Spot is thought to be a Perpetual storm recently images from a new probe that has flown above Jupiter's poles reveal a completely different planet [Music] foreign [Music] [Music] the ancient Romans knew Jupiter as the celestial representation of the king of the Gods in 1610 Galileo using his newly improved telescope saw Jupiter's moons and could see they orbited the planet evidence that not everything revolved around the earth as the church had declared though better telescopes improved our view of Jupiter it was not until 1964 that Gary flandro a graduate student working part-time at NASA's JPL understood there was a way to get a clearer look at Jupiter by plotting the positions of the outer planets he realized that a rare alignment would enable a spacecraft launched in 1977 to visit Jupiter Saturn Uranus and Neptune NASA jumped the opportunity and began work on Twin craft for what was then known as the planetary Grand Tour to limit any surprises two basic spacecraft known as Pioneer 10 and 11 were quickly built they would go ahead of The Grand Tour missions to send back information about the environment toward Jupiter in March 1972 was the first spacecraft across the asteroid belt that lay between Mars and Jupiter and because it was the first Probe on a trajectory that would take it out of the solar system it carried a plaque identifying its origin by December 1973 Pioneer 10 was sending back pictures of Jupiter clearer than anything that had been seen before [Music] approaching Jupiter it encountered levels of iron radiation ten thousand times more intense than the radiation belts surrounding Earth as the probe skimmed past the giant planet it gained speed leaving Earth Pioneer 10 was moving at 51 000 kilometers per hour departing Jupiter it had more than doubled its speed this gravitational slingshot effect made The Grand Tour possible The Grand Tour craft recently renamed Voyager 1 and 2 were due to be transferred to Cape Canaveral for launch integration when news of Jupiter's extreme radiation environment came through the electron radiation at Jupiter had generated false commands within pioneer 10. with the far more sophisticated voyages this presented problems local supermarkets were stripped of their stocks of kitchen-grade aluminum foil which was then used to Shield critical cables without this last minute alteration electrical pressures of up to 40 000 volts would have been induced in the Voyager subsystems as the craft passed Jupiter Voyager 2 was launched in August 1977. its trajectory meant that it could visit Jupiter Saturn Uranus and Neptune system Voyager 1 left 16 days later it's different faster trajectory only allowed flybys of Jupiter and Saturn and various large moons [Music] at the time the Voyager spacecraft were the most sophisticated probes to be launched because they were to operate at huge distances from the Sun solar panels could not be used as a power source they were equipped with radio isotope thermoelectric generators which used the heat from the decay of plutonium-238 to generate power as Voyager 1 approached Jupiter in January 1979 it began sending image sequences that showed a complex and dynamic planet the planet's giant red spot was revealed as a vast rotating storm in 1665 Giovanni Cassini described a permanent Spot on Jupiter which was regularly observed into the 1700s it was not until the late 1800s the Jupiter's spot was described as red and it's uncertain whether the historic observations of Jupiter's spot refer to the same feature or a phenomenon that regularly manifests in Jupiter's atmosphere Voyager 1 made its closest approach early in March 1979. as the probe near Jupiter the activity at NASA's jet propulsion laboratory became intense this was the nature of the voyager's flyby missions though a long quiet Cruise phases between the planets followed by brief periods when the flow of information from the craft overwhelmed researchers [Music] one of the biggest contributions made by the voyagers was the transformation in our understanding of the Galilean moons previously just dots of light Jupiter's four largest moons were each distinct and completely different [Music] the first surprise was the inner Moon IO it's a sulfurous yellow in appearance and one particular long duration exposure revealed an odd plume rather than being a cold dead world the gravitational squeezing IO receives from its giant neighbor heats the moon's interior the plume was a volcanic eruption ejecting material hundreds of kilometers above the surface in July 1979 three months after Voyager 1 had moved Beyond Jupiter Voyager 2 made its closest approach it was able to examine different moons more closely than its twin Europa was the next surprise it is highly reflective and has the smoothest surface of any body in the solar system further observation revealed pressure ridges reminiscent of Polar Ice flows on Earth Europa is a frozen world with a vast ocean beneath a thick crust of ice like IO it is heated from within by tidal flexing as Voyager 2 continued towards Saturn planetary researchers were left with large amounts of raw data about Jupiter still to be processed the Voyager missions left us with a basic view of the Jovian system but they had raised more questions than they were able to answer it would be more than 10 years before Jupiter received another visitor from Earth Mission and liftoff of Discovery and the Ulysses spacecraft found for the polar regions of the Sun in October 1990 the Space Shuttle Discovery lifted the European Ulysses spacecraft to low earth orbit from there it was boosted on a mission to observe the Sun but first it would pass Jupiter all the planets orbit the Sun in the same direction in roughly the same plane this is called the ecliptic and it developed from the spinning disc of dust and gas that formed our solar system designers of the Ulysses spacecraft wanted to see the Sun from an orbit above its poles Jupiter's extreme gravitation was used to bend the probe's flight path out of the ecliptic so it could make north-south orbits off the Sun Ulysses was not the only probe to take advantage of Jupiter's gravity both the Cassini probe to Saturn launched in 1997 and the New Horizons probe to Pluto launched in 2006 were able to reduce their flight times by years with Jupiter flybys these probes were able to make meaningful observations while passing the giant planet [Music] in the clean rooms of the jet propulsion laboratory a new probe was taking shape Galileo would be the first spacecraft to go into orbit around Jupiter its 4.8 meter antenna was folded like an umbrella only to be deployed when safely on the way to Jupiter foreign ly scheduled to launch in 1986 it sat in storage for years after the space shuttle Challenger exploded [Music] it launched aboard space shuttle Atlantis in October 1989. ignition and liftoff of Atlanta new rules governing shuttle launches meant a change in the booster to push Galileo out of Earth orbit the less powerful solid fuel upper stage now stipulated sent Galileo toward Venus for a gravity assist the new flight path meant Galileo was traveling to a hotter part of the solar system it was decided to keep the heat sensitive antenna furled until after the spacecraft Loop backed past Earth Galileo made two close passes of Earth each time gaining more speed its first pass was in December 1990 more than a year after its launch a further year on when it passed Earth again the High Gain antenna was only partially open after months of trying different techniques to deploy the antenna Mission Engineers concluded that long periods in storage had caused lubricant at the tips of the antenna's ribs to dissipate researchers would rely on Galileo's smaller antenna with data delivered at slower rates during the cruise to Jupiter Galileo encountered several asteroids this is Ida the first asteroid we've learned of with its own Moon dactyl in July 1995 while it was still six months away from its closest encounter with Jupiter Galileo ejected a small probe designed to enter the atmosphere and Sample its chemical composition the probe lasted for an hour in Jupiter's atmosphere the data was relayed to Galileo and recorded for subsequent transmission back to Earth its analysis revealed hardly any water vapor which was unexpected and other elements particularly helium were detected at far lower levels than predicted the probe experienced areas of extreme heat and cold suggesting heat is being released from the planet's interior slightly more than an hour after transmission from the probe ceased Galileo began its orbit insertion burn its engine had to operate for 49 minutes to put it into a highly elliptical equatorial orbit but this orbit would be altered with another burn at its High Point Mission designers were acutely aware of the high radiation environment and the second burn would lift Galileo above the extreme radiation at its closest approach Galileo's initial orbit eventually delivered a close approach to Ganymede Jupiter's largest moon during this orbit Engineers were trying to understand damage to the spacecraft's vital tape recorder without its High Gain antenna the recorder was essential for slow replay of data recorded during the brief Close Encounters it had been stuck in rewind for 15 hours and tape had been degraded light emitting diodes key elements in the Recorder's control system had acquired radiation defects the second orbit also passed Ganymede Galileo discovered it's the only moon in the solar system with a significant magnetic field it also has an ocean sandwiched between two layers of ice Galileo's orbits would be slightly varied so that it could make close approaches to different Jovian moons but the equatorial orbits needed to reach the moons also took the craft through hot spots in Jupiter's radiation belts with the observations made by the Voyages the moon Europa was of particular interest to the Galileo team data from several instruments agreed that a salty ocean exists beneath europa's surface ice later examination of the Galileo data sets revealed plasma wave and magnetic field information showing that plumes of water vapor were erupting from cracks in the surface Europa has more water than Earth which makes it a possible home to life IO was already known to have volcanic activity but Galileo saw tides in the moon's solid surface of more than 100 meters the temperature is generated by this gravitational Distortion of i o make its numerous volcanoes hotter than anything found on Earth during its eight years at Jupiter Galileo completed 35 orbits filling out our limited picture of the Jovian system this was never an easy mission Galileo was a robust spacecraft but the radiation environment stressed all the subsystems and Engineers were constantly having to find workarounds for the frequent breakdowns Galileo suffered instruments showed increased noise when near Jupiter and current leakages caused by radiation led to several resets of the onboard computer with crucial loss of data software changes enabled the computer to recognize these resets and to recover by itself information learned would lead to changes in the way the next Jupiter spacecraft was designed five four three two one ignition and liftoff of the atlas V with Juno on a track to Jupiter in August 2011 Juno began a journey to Jupiter that would last almost five years its Mission parameters would be very different to Galileo's it would ignore the moons and focus exclusively on Jupiter Plateau spacecraft design saw crucial Electronics shielded within a thick titanium Vault and rather than a plutonium power source Juno would rely on solar panels the sun's intensity at Jupiter is roughly five percent of what it is at Earth so the panels are huge a shortage in stocks of plutonium-238 led to the change in power sources [Music] Juno followed a looping orbit that took it Beyond Mars before swooping back to Earth for a gravitational boost that added 14 000 kilometers per hour to its velocity sending it on to Jupiter [Music] Juno approached Jupiter on a path that took it above the planet's North Pole it was destined for a north-south orbit this would see it pass beneath the severe sections of the planet's radiation belts that extend out from Jupiter's equator four days before its closest approach Mission Control sent a command that initiated the Craft's autopilot on July the 4th 2016 Juno began an engine burn that would insert it into a 53-day orbit [Music] 48 minutes later Mission Control JPL received tones verifying that Juno had started its deceleration maneuver it was a tense 35-minute wait from the systems Engineers before confirmation came through that Juno had performed exactly as intended [Music] thank you for the Juno scientists and Engineers it was a relief that things were going to plan do you know Juno is equipped with a suite of instruments capable of penetrating Jupiter's thick cloud the polar orbit allows Juno to compile a three-dimensional map of the upper atmosphere building a picture of the entire planet as it rotates the images of Jupiter from this New Perspective appear to come from a different planet researchers were stunned it was planned that Juno would only make two 53-day orbits and then change to a series of 14-day orbits that would speed up the sampling rate the spacecraft's main engine is fueled by hydrazine and nitrogen tetroxide which ignites spontaneously when mixed the propellant and oxidizer are forced out by a bladder of expanding helium as Juno was finishing its second orbit the helium valves were not responding correctly so it was decided to maintain the original orbit emission extension has been granted to allow for the longer orbits Juno continues to follow within a day of the helium valve problem Juno went into safe mode all instruments went offline and data was lost it appeared to be similar to the difficulties experienced by Galileo but Engineers traced the issue to a data transfer problem from one specific instrument and the spacecraft remains healthy Jupiter's axis is tilted at only three degrees making even an oblique view of the poles near impossible until Juno arrived when viewed in the infrared researchers saw a complex arrangement of storms at both the poles at the North Pole a central Vortex is surrounded by eight anticyclones at the South Pole five anti-cyclones surround the central storm scientists do not understand why the storms all rotating in the same direction do not obliterate each other [Music] on its seventh close pass of Jupiter Juno flew directly over the giant red spot its microwave radiometer was able to map the heat distributions at varying levels down to 350 kilometers the red spot is a giant storm and Juno was able to see much higher temperatures at the deepest levels they could penetrate with no geographic features as on Earth there is nothing on Jupiter against which storms can dissipate the Great Red Spot remains firmly 22 degrees below the equator yet it appears to have drifted around the planet at least 10 times since reliable observations began Jupiter's magnetosphere is huge it traps charged particles in bands stretching out to vast distances this gives sensitive Electronics on orbiting spacecraft like Juno big problems it was assumed that Jupiter's magnetosphere was generated like Earth's by Dynamo action the convective movement of an electrically conductive fluid deep within so far results from Juno suggest that this is not the case the lumpy nature of Jupiter's magnetic field points to an atmospheric Source the giant auroras at the poles also seem to come from a different mechanism than here on Earth by focusing on the composition of the gas giant researchers are hoping to gather clues about conditions at the formation of the solar system while the Earth has been continuously Changed by tectonic forces it is thought that Jupiter remains very similar in composition to the cloud of gas and dust from which the solar system was formed [Music] at the end of its Mission Juno will be sent on a collision course with Jupiter to avoid any possible contamination of the delicate moons the next mission to the Jovian system will focus on Europa as the most likely place after Earth to Harbor some form of life known as Europa Clipper it's scheduled to launch in 2022 like Juno it will be solar powered and its elliptical orbit of Jupiter will see it fly over Europa every two weeks [Music] early concepts for the mission called for the inclusion of a Lander but this idea was soon rejected as premature because more needs to be learned about the surface of the icy Moon [Music] thank you though europa's ice crust is thought to be at least 19 kilometers thick accurate measurements need to be made if thin areas can be found then future missions may be able to access the ocean that Lies Beneath [Music] concepts for under ice explorers are in development and we can expect other missions to focus on other moons [Music] as the largest planet Jupiter's influence on the rest of the solar system is profound it has more than twice the mass of every other planet combined all other planets orbits are affected by Jupiter's gravitation [Music] to learn about Jupiter some of our Solar System's planets have been visited by scientific probes less frequently than others [Music] the outer gas giants Uranus and Neptune are so distant they're hard to reach Uranus is 20 times further from the Sun than Earth while Neptune is 30 times further [Music] both have only been seen at close range by NASA's Voyager 2 spacecraft Mercury is so close to the Sun that any probe sent in its direction must take a circuitous path to offset the sun's immense gravitational influence the Mariner 10 probe flew past mercury in 1973 and the messenger probe went into orbit around mercury in 2011. Venus presents different problems though it's our closest planetary neighbor and easier for spacecraft to reach dense Cloud hides its features and its surface has hellish conditions the Russian veneracraft have landed but in the hostile environment they could only survive for minutes foreign [Music] roughly twice every Century the planet Venus passes between the Earth and the Sun called the transit of Venus it was closely observed in 1769. astronomers realized that careful timing of Venus's passage across the face of the sun would allow them to calculate the distance to the sun which in turn would unlock far more accurate methods of navigation [Music] in 1961 the Soviet Union launched Venera 1 the first Venus probe it passed Venus as intended but Mission Control had lost contact with it foreign the following year NASA launched marinawanda Venus we're not on trajectory a coding error led to control problems with the launcher destroyed minutes after liftoff because convenient launch opportunities only occur in 18-month Cycles NASA had a second probe ready to Launch Mariner 2 was essentially a ranger spacecraft designed to go to the Moon these were the early days of the Space Race and the United States was desperate to catch up with the Soviet Union lead times were short and the jet propulsion laboratory did not have time to complete its original design [Music] in August 1962 Mariner 2 was launched the ranger spacecraft launched toward the moon had all failed Mariner 2 on its way to Venus was functioning but its Transmissions were weak and due to a launch anomaly it was off course after a week instructions for a complex course correction were transmitted to the spacecraft about an hour later Mariner executed the maneuver which involved a roll turn followed by a pitch turn and finally a main engine burn foreign [Music] well but several days later the craft lost lock on the Sun and the Earth its two attitude reference points it corrected itself before Ground Control could diagnose the problem next the signal strength increased to its normal level but a short in a solar panel left it low on power [Music] this time although both America and the Soviet Union had been sending probes toward the planets nothing had succeeded Mariner 2 lost several Telemetry sensors and it began to overheat it continued limping toward Venus but some of the spacecraft's problems were solving themselves Mariner 2 was now close enough to the Sun that it could function effectively on just one solar panel past slightly less than 35 000 kilometers above Venus's Cloud tops it could detect no planetary magnetic field and it recorded temperatures across the planet approaching 500 degrees Kelvin clearly landing on the surface would present problems [Music] first real success in space finally doing something that the Soviets had not Mariner 2 was the first successful interplanetary probe and in California the home of JPL they celebrated [Music] the next major advances in the exploration of Venus were made by the Soviet Union the objective of the Venera series was to land on the surface of Venus designed as understood that not only were the surface temperatures hot enough to melt lead but that the atmospheric pressure was many times that of Earth the Landers they built looked more like diving Bells than spacecraft in June 1967 Venera 4 was launched the vehicle consisted of a carrier craft with instruments used during the cruise phase to Venus and a spherical Landing module that could communicate independently after entering to the atmosphere Venera 4's parachute opened sent back data for 93 minutes but stopped 28 kilometers above the surface [Music] yet its Electronics hadn't been overwhelmed by the heat it had simply run out of power extrapolations from its final measurements showed a surface temperature of 500 degrees Celsius and a pressure of 75 atmospheres far higher than anyone expected the Venera program strengthened its Landers and fitted smaller parachutes to reduce descent time launched in January 1969 Venera 5 and 6 learned more about the chemical makeup of the atmosphere but neither remained functioning at the surface foreign the Venera series continued refining the technology and making incremental improvements to Mission duration adding to the knowledge about Venus in 1975 Venera 9 was launched it was a new design consisting of an Orbiter Lander combination with the Orbiter able to act as a relay station for signals transmitted from the surface four months after launch the Orbiter and the Lander encased in a spherical shell separated it entered the atmosphere two days later while the mothercraft became the first probe to go into orbit around Venus photographing parts of the surface in ultraviolet [Music] the new Lander had a ring Shield that could replace a parachute during the latter stages of The Descent through the dense atmosphere thank you Venera 9 transmitted the first black and white pictures from the surface though a design fault meant a second camera could not eject its lens cap three days later and two thousand kilometers away a twincraft Venera 10 Landed It took pictures too but the same design fault left a lens cap stuck in place both Landers had been pre-cooled while still in space and circulating cooling fluid kept the craft operating on the blistering surface for more than an hour foreign 1983 two more Venera craft arrived at Venus equipped with synthetic aperture radar they made the first serious attempt to map the surface beneath the cloud layer over eight months they mapped from the North Pole down to 30 degrees north [Music] Demarest 10 9 8 7 6. NASA had taken a minor role in the early exploration of Venus but in 1989 the space shuttle Atlantis lifted off carrying the Magellan probe Magellan was bound for Venus like the Venera craft before it Magellan would use radar to map the surface of the planet it was the first interplanetary spacecraft launched from the space shuttle following a cruise of 15 months Magellan arrived at Venus and entered an elliptical orbit to keep costs down the probe had been built from an agglomeration of spare parts left over from previous NASA missions after some software problems it began mapping the images it relayed remained the highest resolution pictures we have of the surface of Venus pictures of low volcanic blisters emerged and lava channels were evidence of an extremely active surface the thick atmosphere has prevented all but the largest meteors reaching venusian ground and few impact craters were visible yet evidence of plate tectonics that sculpts the Earth's surface was not obvious after mapping Venus Magellan changed its orbit and plotted the planet's gravitational anomalies on Venus localized changes in gravity correspond to surface features on Earth this is not the case a new naked picture of Venus emerged the surface appears to have been completely remade around half a billion years ago yet while volcanoes and lava channels are common features on Venus Magellan could not find evidence that volcanic activity still happens on the planet in 2006 the European space agency's Venus Express went into orbit around Venus its focus was the long-term analysis of the planet's atmosphere during its eight-year Mission it registered a sharp rise in the atmosphere's sulfur dioxide this could be due to changes in Wind patterns but it could also be a sign of volcanic activity researchers also saw increases in infrared radiation coming from three different volcanic locations more circumstantial evidence of current volcanic activity finally the infrared team saw short-term temperature changes that fluctuated over just a few days it appears that volcanoes may still be active on Venus [Music] the mission ended in 2015 with a series of swoops into the upper atmosphere that verified unexpected ripples in the mesosphere very little in the way of Venus exploration has happened since Venus Express though elaborate plans exist for future missions to Venus nothing at this stage has been funded [Music] yet many missions still pass close to Venus to use its gravitation to alter their flight paths in 1974 Mariner 10 was the first spacecraft ever to use the gravitational slingshot effect on its way to Mercury Italian mathematician Giuseppe Colombo devised the maneuver as a way to save fuel and to fly past Mercury not once but several times the technique is now commonplace ten days after launch Mariner 10 executed instructions for a routine course correction this appeared to go well but after the burn when the craft attempted to reorient itself there was a problem Mariner 10 knew where it was pointing because its tracking sensor could lock onto the star canopus but a flake of paint that had come from the spacecraft was confusing the system an automated backup procedure found canopus again but flaking paint was an issue for the rest of the mission to reach Mercury a spacecraft must approach the Sun and its immense gravity presents a problem voyages to outer planets are constantly slowed by solar gravity but with the inner planets a spacecraft constantly accelerates Mariner 10 used Venus's gravity to reduce its speed and it approached Mercury at an acute angle Mariner 10 did not have enough fuel to go into orbit around Mercury but its sun-centered path allowed the probe to make three close passes its first pass revealed a moon-like planet with a heavily cratered surface though Mercury is the smallest planet it's the most dense it has a large iron-rich core prominent escarpments were seen here Discovery scarp cuts through two craters it falls three kilometers it's thought that these Cliffs are the result of cooling and shrinking of the core Mariner 10 continued to suffer technical problems its tape recorder kept sticking there were restrictions in the rates of data transmission and limited attitude control meant flight Engineers were using solar pressure on the High Gain antenna and solar panels to compensate yet the mission continued Mariner 10 could only map about 45 of Mercury's surface as the same hemisphere faced the Sun during each of its passes Mariner 10 discovered a very thin atmosphere primarily of helium several months after its third and final pass of mercury it ran out of fuel it still orbits the sun main engine start two one and it was more than 30 years before the next mission to Mercury in 2004 messenger was launched it was designed to go into orbit around Mercury which presented a number of design constraints it featured a large woven ceramic sun shield but it did not have a dish antenna it would rely on a phased array that could be electronically pointed after a year in space messenger was back at Earth using its gravitation to modify its orbit even though it was not a large spacecraft it had a powerful engine for course Corrections and orbit insertion it continued on to pass Venus twice to lose speed as it drew closer to the Sun [Music] three and a half years after launch messenger approached Mercury but this was not the end of its Journey the probe made two more passes of mercury before finally going into orbit after almost seven years in space Mission Engineers had the extra problem of always requiring the probe sunshield to be pointed toward the Sun because it was in orbit messenger was able to complete the mapping started by Mariner 10. the planet's dominant feature is the caloris Basin it's an ancient crater more than 1 500 kilometers across Mariner 10 saw some of the area but the rest had been in darkness this map of the Southern polar region uses color to represent illumination because Mercury's axis is not tilted sunlight cannot penetrate deep craters near the poles it was in these areas that messenger discovered substantial amounts of Water Ice messenger received several Mission extensions but in 2015 it crashed into Mercury after running out of fuel a new mission is already on its way to Mercury depi Colombo named after the designer of Mariner 10's trajectory it's a joint effort between jaxa the Japanese space agency and the European Space Agency will take seven years to reach Mercury the Voyager 2 spacecraft is the only probe to have made close approaches to the two outer ice giants Uranus and Neptune launched in 1977 with its twin Voyager 1. it was able to take advantage of a rare alignment of the four outer planets enabling it to make close observations of each one in 1986 Voyager approached Uranus in the distant past it must have been hit by another massive body that knocked its axis sideways Uranus has an East and a West pole and for half its orbit one side sees continual sun while the other remains in darkness it has rings which follow its north-south equator [Music] Voyager 2 discovered 11 new moons and a misaligned magnetic field images that the Voyager captured showed Uranus as a bland featureless planet but this was because of its particular season with images from the Hubble Space Telescope we now know that at certain times clouds and planetary weather appear in the atmosphere Uranus's largest moon Miranda was observed in detail for the first time so chaotic is its surface that researchers thought that it must have been blown apart by some Cosmic impact with the fragments reforming now it's thought that tectonic forces initiated by the gravitation of Uranus are responsible for the moon's jumbled appearance [Music] zoyager 2 left Uranus backlighting from the Sun revealed two new Rings encircling the planet [Music] spacecraft was now heading toward Neptune the Solar System's last planet in the three years it would take to get there ground Engineers began preparing for Unique challenges [Music] Neptune is 30 times further from the Sun than the Earth and the light intensity is one thousandth what it is here [Music] for photography time exposures would be necessary yet Voyager 2 was traveling so fast that images would spear without special preparation [Music] Engineers calculated just how much the craft would have to swivel while exposures were made to compensate for the probe's movement [Music] in June 1989 Voyager 2 began returning distant images of Neptune across the world people had realized that the data sent back to Earth by this spacecraft was Transforming Our understanding of the solar system [Music] foreign this was before the internet age researchers are the jet propulsion laboratory clustered around TV sets to watch as data and images came in line by line [Music] and it's a more conventional Planet than Uranus Excel tilt is 30 degrees and it revolves in the same direction as Earth [Music] while Neptune is slightly heavier than its fellow ice giant Uranus it has a slightly smaller diameter and that is further from the Sun than its neighbor Neptune emits more heat than Uranus the planet has an internal heat source that drives more Dynamic weather patterns Voyager 2 measured wind speeds at Neptune in excess of 2 000 kilometers per hour the fastest in the solar system there were cirrus clouds in the atmosphere and the probe recorded pictures of a Great Dark Spot similar to Jupiter's Great Red Spot it was an anti-cyclone in the southern hemisphere as large as the Earth [Music] in 1994 when Hubble tried to find the same feature it had disappeared but a new dark spot was forming in the northern hemisphere Voyager 2's last observations within the solar system were of Neptune's largest moon Triton unlike all other moons in the solar system Triton has a retrograde orbit indicating that it was not formed at the same time as the planet but that it had been captured as Voyager 2 moved beyond the planets its cameras were Switched Off to save power both voyagers continue away from the solar system measuring the influence of the solar wind this Remains the only mission to the ice giants on January the 19th 2006 an atlas V was launched it was a very powerful rocket with an unusually small payload New Horizons left Earth orbit faster than any other probe it was headed for the Kuiper belt at the outer edge of the solar system in particular Pluto in a little more than a year New Horizons reached Jupiter where it received a gravitational assist that cut three years from its flight time to Pluto after it passed Jupiter the spacecraft went into hibernation simply sending an allswell transmission once a week it took New Horizons more than nine years to reach Pluto since it had departed Pluto had lost its status as a planet with the discovery of more objects of similar size in the Kuiper Belt It was decided that to be a planet a body had to clear its orbit [Music] Pluto's features surprised everyone here was a living planet shaped by tectonic forces but instead of rock the mountains were made of ice and Frozen methane and Pluto has a thin atmosphere mainly of nitrogen the probe continued on over current Pluto's largest moon icy surface has deep canyons and some evidence suggests that it has ice volcanoes [Music] Karen is about half the size of Pluto and the two orbit each other from Pluto Karen would appear Motionless In The Sky as the New Horizons probe sped away from Pluto into deep space it began the slow process of transmitting its recorded data back to the Earth at these distances it takes signals four and a half hours to reach Earth with data coming in at one kilobit per second took 469 days for all the Pluto information to be received back on Earth [Music] early in 2019 New Horizons passed Trends neptunian object Ultima Tooley and with a mission extension it continues exploring the outer reaches of the solar system [Music] the Earth is our home our natural environment results from complex relations between the Sun the oceans and the atmosphere [Music] a polar ice and the tropical heat represent the extremes of our planet's climate in reality this is a very narrow temperature band completely different from any other planet we've observed the stability of the Earth's environment has allowed life to emerge and life has changed the planet as far as we know the Earth is the only planet in the universe to have given rise to life [Music] [Music] the Orion Nebula is a vast cloud of gas and dust in the Orion constellation it's a place where new stars are being created as part of the nebula condenses it separates into clumps as each Clump contracts under its own gravitation it begins to swirl flattening into a disc they're called protoplanetary discs or proplets in the center of a proclid as the molecules are squeezed together a fusion reaction begins and a star ignites some proclides occurring close to an established star shine brightly under the influence of their neighbor while this makes them easier to observe the glowing gas and dust is being Stripped Away by the Stellar winds from the adjacent star dark propellants only observable as Silhouettes maintain their surrounding ring of gas and dust as the system matures this Stellar debris will form a planetary system the Hubble Space Telescope has recorded numerous examples of this process enough for astronomers to understand that the formation of planets is commonplace [Music] this is how our own Sun started its life 4.6 billion years ago but the planets would take longer to emerge small grains within the disk began accreting forming planetesimals the larger a clump became the stronger its gravitational attraction in turn leading to more rapid growth an early version of Jupiter would have been the first to coalesce completely clearing its orbit around a core of heavy metal and rock Jupiter's atmosphere mainly of hydrogen was compressed by its strong gravitation any solid surface lay beneath thousands of kilometers of liquid gas our observations of exoplanets have revealed jupiter-sized gas giants orbiting close to their Stars astronomers believe the young Jupiter would have begun a track toward the sun dragging asteroids and comets in with it but Jupiter's inward path reversed as it was pushed into an orbital resonance with the emerging Saturn not all of the objects forming in the early solar system stayed orbiting the Sun smaller objects passing a planet would be deflected by the stronger gravitation or even captured becoming a moon it is thought that there were up to 20 smaller planets orbiting in the inner solar system from which the four remaining terrestrial planets were formed at this time collisions in the developing planetary system were common and evidence from the Apollo moon rocks suggests an impact between the early Earth and an ancestor of our moon was important in our planet's evolution the Earth has a larger than expected iron core and gravitational analysis of the Moon suggests its core is lighter than expected a collision between the bodies would explain the moon's loss of much of its heavy material to the more massive Earth was a glancing blow that set the Earth rapidly spinning with a five-hour day the Moon that we know coalesced from the molten debris Although our moon is not the largest in the solar system it is closer in Mass to its parent Planet than any other Moon the stabilizing effect that the moon has upon the Earth's rotation is significant over long periods the Earth's axis will vary by as much as one degree without the moon's influence this variation could be as much as 85 degrees with drastic implications for the climate stability the debris in the early solar system was cleared by the planets in a period called for heavy bombardment the emerging Earth was peppered with asteroids and comets delivering water necessary for life while tectonic forces erased the bombardment scars from Earth the moon which endured the same travails is still covered with craters when chaos in the developing solar system settled down the young Earth was in a unique position the Earth's distance from the Sun was just right for the abundance of water on the planet to exist in liquid form as the moon had drifted away the planet's rapid rotation had slowed and the sun's heat was evenly shared across the surface the Earth's large metallic core combined with the planet's rotation meant that a magnetic field stretched out around the planet deflecting the charged solar wind and protecting the surface from extremes of solar radiation in a hostile Universe the Earth was a uniquely benign environment the geological record shows that around 2.7 billion years ago oxygen began occurring in the atmosphere the vast iron ore regions of Western Australia were formed as iron in the oceans reacted with the new abundance of oxygen to form iron oxide simple plant life was using the sunlight and carbon dioxide to live and It produced highly reactive oxygen as a waste product this enabled more complex life to emerge building an intricate web of interrelated plants and animals completely transforming the planet [Music] the change in the atmosphere had other dramatic consequences oxygen stripped much of the highly insulating gases from the air drastically cooling the Earth a sequence of ice ages began though there is an abundance of evidence showing planetary glaciation punctuated by warm periods the factors triggering these Cycles are complex fold lines are Clues to the movement of continents leading to diversions of ocean currents the effect of volcanic activity on the atmosphere and changes in the direction of the Earth's axis with regard to our planet's elliptical orbit around the sun all contributors to long-term fluctuations in the earth's climate analysis of ice cores deposited in the Antarctic or Greenland is an accurate way to see how the composition of the atmosphere has changed over the previous 800 000 years bubbles of air caught between snowflakes before being rigidly trapped as the snow becomes ice can be accurately sampled one thing is clear carbon dioxide reaches a peak of around 270 parts per million during The warm periods and drops to approximately 170 parts per million when glaciation is at its greatest but from this data it's hard to know if extra CO2 causes the warming or the warming leads to extra CO2 in 1958 Dave Keeling working for the Scripps Institute began recording accurate levels of atmospheric CO2 at the maunaloa observatory in Hawaii it was the beginning of a unique record known as the Keeling curves [Music] keeling's graph revealed a seasonal variation corresponding to spring and summer in the northern hemisphere where land mass and plant cover is greater during the northern spring and into the summer CO2 levels dropped because of the increase in photosynthesis by the 1970s a disturbing Trend had emerged CO2 levels were in a steady rise at first there was uncertainty about the implications extra CO2 could trap more Heat leading to a warming effect known as the greenhouse effect but some scientists were worried that aerosol pollution could attenuate levels of sunlight reaching the planet resulting in a cooling environment as the decades passed different pieces of evidence were collected drill cores from the ocean floor revealed that ice ages had been triggered by milankovic Cycles the variations between Earth's Tilt and its elliptical orbit though these effects were minor the correlation was obvious if such a small nudge could alter the climate perhaps changes in CO2 could as well scientists were realizing just how poorly they understood planet Earth [Music] Cape Canaveral carrying a robot weatherman into orbit for America at the beginning of the Space Age scientists were Keen to make weather observations from orbit launched in 1960 tyros 1 was the first weather satellite it was equipped with two TV cameras regularly transmitting images of global Cloud patterns it provided meteorologists with a unique View and it was followed by improved versions because these early satellites were in highly inclined low earth orbits the data gathered covered the whole planet and it was shared across the world 1873 Nations had been cooperating on weather prediction via the international meteorological organization which in 1951 became the World Meteorological organization an arm of the United Nations headquartered in Geneva with a UN resolution calling for international cooperation in the peaceful uses of outer space weather satellites of different nations were soon being coordinated for the benefit of all mankind in 1964 the program began series of seven satellites included a more sophisticated set of sensors [Music] Nimbus was a test bed for new technologies and it gathered data about different areas along with Cloud patterns was information about the atmosphere and sea ice [Music] this was the pre-digital age and all electronic image data was burnt to and stored on 70 millimeter film little thought was given to establishing an archive for future reference [Music] program was an early example of Earth observation rather than just a group of weather satellites a meteorologist started seeing the planet as a complex and interconnected system today a fleet of satellites is in operation monitoring the atmosphere the oceans the ice the land and the biosphere it is now understood that ice particularly sea ice plays an important role in the earth's climate system Polar Ice slowly flows to the coasts where it melts providing a source of cold water that drives the ocean currents responsible for the transfer of heat from the equatorial regions to the poles these currents also move nutrition which is important for the survival of life global winds also circulate water via clouds keeping the land moist and able to support vegetation plant life in both the oceans and the atmosphere removes CO2 from the air and replenishes the atmospheric oxygen both the ice known as the cryosphere and the clouds reflect a proportion of the sun's energy back out into space the extent of the ice and cloud cover are important factors in the Earth's energy budget as ice melts it exposes Ocean or Rock which absorbs more solar energy similarly cloud cover or the absence of it will have an effect upon the land or sea beneath vegetation is also an important climate Factor as land plants pump huge amounts of water vapor into the atmosphere but things are changing Humanity simply through weight of numbers is influencing key elements of the planet's climate system in 50 years the Earth's human population has risen from just over 3.5 billion to 7.7 billion today or people need more resources and while there have been Revolutions in agriculture and in technology the Earth's reserves are not Limitless in 1979 Europe began launching spacecraft and while the new Earth observation satellites were revealing changes scientists were reluctant to reach conclusions about long-term trends they understood that there was a certain amount of variability in the planet's climate cycle and though climate science knew about the steady rise in atmospheric CO2 revealed by the Keeling curve researchers were looking for additional solid evidence that change caused by human activity was happening since 1913 spectroscopy had revealed that a layer of ozone in the stratosphere blocked harmful UV sunlight from reaching the ground in 1974 Mario Molina a postdoctoral fellow working on hot atom chemistry published a paper suggesting that the family of industrial chemicals known as chlorofluorocarbons or CFCs could damage the ozone layer in the 1980s meteorologists working in Antarctica found the evidence the polar vortex above the southern continent concentrates the CFCs in the stratosphere mother of pearl clouds in the polar Skies contain ice crystals which in combination with ultraviolet split chlorine from the CFC molecule each chlorine atom can break down over one hundred thousand ozone molecules a large area centered over Antarctica showed almost no ozone became known as the hole in the ozone layer the United Nations began talks aimed at limiting the production of CFCs and in 1989 an international treaty known as the Montreal protocol capped the production of CFCs and ultimately resulted in a 10-year phase out of CFC production all countries signed the agreement and the Montreal protocol is seen as a model of international cooperation in the 1980s an upward Trend in global temperature averages was becoming clear and a scientific consensus emerged that the burning of fossil fuels was altering the balance of gases in the atmosphere most of our planet's fresh water is locked in the polar ice caps 61 of this ice covers the Antarctic continent in the north Greenland is also covered by an ice sheet there is no land mass at the North Pole but a large area of sea ice grows and shrinks with the seasons seasonal sea ice also fringes Greenland and Antarctica ice shelves are a third manifestation of Polar Ice these are thick layers of ice that extend into the ocean from the mouths of glaciers periodically icebergs will break away from these regions these areas are important to the circulation of global winds and ocean currents and since 2002 NASA has tracked the prevalence of water in general and ice in particular via the grace satellites which were recently replaced by a similar pair of Grace follow on satellites [Music] the two follow the same orbit and minute changes in the earth's gravitational field will cause them to change speed with a variation in the distance between them this data is accurately measured allowing researchers to record changes due to variations in groundwater or in ice thickness during the life of the first Grace Mission Greenland lost 285 gigatons of ice per year on average Antarctica lost 137 gigatons per year from 2005 to 2016 sea levels Rose by 3.7 centimeters due to Melting ice sheets and to expansion of seawater sea levels have been monitored from space since 1992. initially with the topics Poseidon satellite and more recently with the Json series of satellites Jason 3 uses a Precision radar altimeter to measure Regional and Global variation in sea levels in the 20 years to 2014 the average rise was six centimeters but the increase is not uniform the red areas show the greatest rise with white representing no change and blue signifying a decrease the unevenness of the sea surface is due to a complex interaction between ocean currents the Earth's Spin and the Topography of the ocean floor all these factors must be accounted for to arrive at a baseline against which to measure changes these blue areas in the Atlantic show a shift in the Gulf Stream the kamag region of Southern France is a low-lying area at the Delta of the Rhone river in the 1980s a sea wall was built to prevent the encroaching Mediterranean over the last 30 years the coastline here has been pushed back by several hundred meters scientists are convinced that a warming global climate is responsible and that our alliance on the burning of fossil fuels has led to an excess of carbon dioxide in the atmosphere which traps Heat 93 percent of this heat has been taken up by the oceans data from the Argo network of ocean boys shows an average warming of 0.9 of a degree celsius since the 1950s while this may not sound like much meteorologists understand how sea surface temperatures Drive hurricanes and Cyclones and early predictions of storms of Greater magnitude are being realized long-standing weather records are being broken and broken again in 2017 NASA NOAA and the UK Met Office all agreed that 2016 had been the hottest year on record globally 16 of the 17 hottest years have all occurred since the year 2000. [Music] both NASA and Esa have been monitoring the distribution and concentrations of CO2 in the atmosphere since 1992. this visualization from data collected in 2006 shows the yearly fluctuations of carbon dioxide and carbon monoxide While most CO2 emanates from the populist northern hemisphere seasonal fires in Africa Australia and South America generate much of the carbon monoxide prolonged droughts and more severe forest fires are another aspect accompanying increased levels of atmospheric CO2 that are currently unfolding such events inject a huge pulse of greenhouse gases into the atmosphere magnifying the problem the European space agency's Copernicus program with its Sentinel Earth observation satellites has committed to making information about the changing climate freely available to policy makers businesses and research institutions Joseph ashbacher is issa's director of Earth observation programs what you see here on this graph is the CO2 concentrations of the atmosphere over the last 800 000 years and you see that these values are going up and down in different phases you see on the the blue lines here are indicating ice ages and the Orange Lines here indicating periods between ice ages or periods where it's much warmer but you also see that over the last 800 000 years the value was always below 300 parts per million and suddenly since the last century it goes up very steep towards 400 parts per million or even Beyond distinguish delegates the recent climate Summit cop 25 held in Madrid made little progress toward an international agreement to cut greenhouse gas emissions while some businesses and economies will have to adjust that task only gets more difficult as time passes and far greater adjustments will be forced upon everyone the Earth is the only place we know that Harbors life but the stability that has enabled this Web of Life is fragile plants and animals interact for Mutual benefit our benign environment results from the complex and varied creatures with which we share the planet it's important that we look after our home [Music]

Channel: Spark

Views: 3,961,046

Keywords: Spark, Science, Technology, Engineering, Learning, How To, education, documentary, factual, mind blown, construction, building, full documentary, space documentary, bbc documentary, Science documentary

Id: 6G5_70PqodU

Length: 129min 3sec (7743 seconds)

Published: Thu Nov 17 2022