Could There Really Be Life On Other Planets In Our Solar System? | Zenith Compilation | Spark

Its foreign neighbor is very cold and dry and its weak gravity only maintains a thin atmosphere. When probes began to visit the red planet we got a more precise view of the surface and scientists began to wonder that Mars had once been much warmer, had rivers and in its early years

could

have supported

life

, a succession of new techniques have been implemented trying to unlock the secrets of the red planet and, although our knowledge of Martian geology, its atmosphere and its climate has grown enormously, each new Mission to Mars raises more questions than it answers. We still don't know if Mars was ever home to

life

.

In 1877, astronomer Giovanni Chaparelli made what he thought was the most accurate map of Mars, but he drew canals on it in the early 20th century. American astronomer Percival Lowell was convinced that the canals were signs of an existing civilization on the red planet, and 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 in the first of many failures. The Cold War rivalry between the Soviet Union and the United States provided the motivation for these first missions in 1971.

NASA sent Mariner 9 to Mars. It was the first probe to orbit an

other

planet, but scientists discovered that Mars was engulfed in a planetary dust storm in orbit. The photograph revealed little more than a foreign Red Cloud. ER 9 was joined by two Soviet orbiters, both equipped with landers. The Mars 2 lander crashed but the Mars Freelander reached the surface intact. It returned a confusing image and then stopped working. Mars now had three in orbit. All the spaceships stared at a featureless, dusty planet. The two Soviet probes were identical, but the American probe had a key design difference, while the Soviet orbiters began photographing the planet on predetermined schedules.

NASA was able to order Mariner 9 to wait in hopes that the dust would eventually disappear. It took months for the atmosphere to clear, but when it did, Mariner 9 saw three craters protruding from the dust. They were the tops of giant volcanoes on what was called the Fasis Plateau. More complex geological features soon began to emerge where the surface was cratered. suggesting that the tectonic forces that constantly renew Earth's surface were absent on Mars. The volcanic activity that formed the largest volcanoes in the Solar System had stopped billions of years ago. This allowed NASA scientists to compile an accurate global map of Mars and decide landing sites for the Viking.

The probes that followed in 1976 were foreign and two were identical orbiters with landers that made successful landings on the surface and both returned images of the Martian landscape. The main goal of the Viking program was to find traces of life, but researchers now believe that the three experiments are tasked with conducting the analysis had limitations when researchers on Earth began searching for traces of life in extreme environments and began to rethink where life on Mars

could

survive, but the consensus at the time was that Mars was sterile and the idea that life on Mars died after a 20-year hiatus in Mars research Mars Global Surveyor entered orbit in 1996.

The images it transmitted were clearer than anything seen so far from the red planet, although most Mars orbiters had been tasked with mapping the planet's surface, this was unlike the high-resolution images. that the Mars Global surveyor sent revealed rivers and even river deltas, but the occasional impact crater suggested that nothing has flowed in these

system

s for billions of years. In July 1997 an

other

probe, the Mars Pathfinder, arrived, it was one of a new generation of missions driven by NASA's new administrator. Under the guiding philosophy of faster, better, cheaper, the idea was to reduce development times, cut budgets and, although the risk of failure would increase, the reduced price could mean more missions.

Pathfinder would land a small rover on the surface to do this. radically new airbag technology, the technique relied more on automotive safety

system

s than previous space missions. The landing site in the northern hemisphere of Mars known as Aris valis is one of the rockiest areas on the planet, but was thought to be a safe area to land the wide range of different types of rocks 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 in future overseas missions. ER consisted of a base station equipped with three

solar

panels that were deployed there like pedals.

They were sensors to measure atmospheric pressure, air temperature and wind speed, as well as a transmitter to communicate with Earth. Additionally, Pathfinder acted as a base station for the Sojourner rover that explored the surrounding area. Sergio was equipped 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 details about the atmosphere and geology and its popularity guaranteed more missions to Mars on the morning of April 7, 2001 another Mars Orbiter was launched Mars Odyssey It was equipped with three primary instruments and had the ability to act as a relay satellite between future servicing missions to the Red Planet and Earth.

Upon arrival at Mars, it used a new technique to enter orbit after firing a relatively brief pulse from its engine. Mars Odyssey entered a highly elliptical orbit that on its closest approach skimmed the planet's thin upper atmosphere called the arrow break. This technique allowed the spacecraft to circulate its orbit for a period of three months and saved around 200 kilograms of fuel. The probe is still in operation today. all records such as the longest mission to Mars in December 2003 a new player reached Mars the European Space Agency using a Russian launcher had sent Mars Express its first planetary explorer was equipped with an owner known as a beagle although everything was lost Contact with Mars Express lander continues to provide valuable data;

The mission has received several extensions, most recently through 2020. Equipped with a high-resolution stereo camera, the probe returned unique 3D views of the planet's surface. The Orbiter determined that the polar caps contain a mixture of frozen CO2. and water Ice in the Mars atmosphere expressed that first methane was detected and then ammonia. Both gases deteriorate rapidly in sunlight, so there must be sources on Mars that continually produce them. Ethane and ammonia can rarely be produced inorganically, but are generally associated with life a month after Mars. Express entered orbit, a NASA lander arrived at Mars, followed three weeks later by a second identical spacecraft, they were the Mars exploration rovers called Spirit and Opportunity Foreign Spirit, the first to land was aimed at the Gusev Crater .

Opportunity would land on Meridiani Platinum on the opposite side of Mars, although they were much heavier than their Pathfinder predecessor, they used the same bounce landing technique. Both landings were successful and hit their target. After the spacecraft righted itself, it separated from the lander and began autonomously deploying its

solar

panels and camera mast while lander. was happening the team in the jet propulsion laboratory waited for signals confirming the safe arrival of the ship it took 15 minutes to travel back to Earth many of these people had invested years of their lives in this project and the actual mission was barely had begun Both rovers were designed to operate for 90 Martian days, a solar day on Mars is approximately 40 minutes longer than an Earth Day and, to avoid confusion, the scientific team operating the rovers refer to a Martian day as a soul.

Mission designers who were aware of dust storms on Mars felt that the solar panels on the two rovers would eventually become blocked with dirt and stop working, but it became clear that the winds on Mars were soon clearing the panels. NASA announced that Opportunity had found evidence confirming that liquid water had once flowed on Mars. There were photographs of the meridians. plane of stratified patterns in the rocks suggesting sedimentation, the distribution of chlorine and bromine at the site were clues to areas past as the coast of a salt sea In April 2004, NASA announced it would extend the rover's missions from three to eight months.

The first of many such mission extensions. The Rovers were equipped with an abrasion tool to polish a portion of a rock surface for more detailed uncontaminated analysis of geological samples. Spirit performed for the first time on a rock called Adirondack in Gusev Crater. It was the first one. In planetary geology, researchers agonized over using the tool because of the drain it produces on the Rover's power budget. The Rock was made of olivine, pyroxine, and magnetite, making it very similar to volcanic basalt on Earth when Spirit's right front wheel stopped working. The engineers used a duplicate Rover. devising a reversing technique that would allow the Rover to drag its frozen wheel, this left a groove in the ground that presented a new area of ​​research for the science team.

The white or yellow deposits seen within the groove were various types of salts that only form in the presence of warm water. On Earth, warm water provides an environment in which microbes can thrive. Spirit limped along for another three years before becoming stuck in the loose sand again. The engineers began working with a replica that they placed in an identical situation where nothing could. To free the rover, a stationary research platform was declared. Further attempts were made to position the rover so that its solar panels could operate more effectively, but even this was not possible. Spirit's last communication was in March 2010.

The opportunity lasted until June 2018, when dust got clogged. its solar panels In March 2006, NASA's Mars Reconnaissance Orbiter arrived at Mars and began the now routine business of breaking down Aero, although this procedure took about six months, the savings and fuel will allow the craft to operate on Mars Until the 2030s, one of the main functions of the new Orbiter is a communications repeater station. Its three-meter antenna that transmits in the ultra-high frequency band allows for very high data speeds. By November 2013 it had tripled the amount of data sent to Earth by all other NASA missions. A combined foreign camera began to reveal the surface. of Mars in the smallest detail these are active dunes that fall in the eastern cobrities chasma the polar region free of seasonal dry ice again surrounded by dunes the southern hemisphere holes in the residual layer of carbon dioxide the poles of Mars were now attracting Great interest follows the Water had become NASA's motto.

The Phoenix Lander was headed to the north polar region to follow up on data from Mars Odyssey that suggested there was frozen water beneath the surface near the poles because images had revealed the region to be unchanging. A Rover was deemed unnecessary. had been designed to use a parachute to decelerate with rocket boosters to bring the craft to the surface, unlike NASA's three previous rovers which had bounced off, this decision proved controversial as one line of research suggested that the fuel from the rocket would contaminate the very area to which the task was assigned. Analyzing the craft, it waited 15 minutes to allow the dust to settle before deploying its solar panels.

Phoenix had landed in early spring in the northern hemisphere of Mars so that the solar panels would receive plenty of light for the planned 90-day mission, as well as for its camera mask. Phoenix was equipped with a weather station that recorded daily weather, It had a wind indicator and pressure and temperature sensors. In addition, a vertically pointed lidar could observe the formation of cirrus clouds in the region and the snow falling in the polar atmosphere. Not previously observed, the Lander also had a robotic arm that could dig half a meter into the ground 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 that gradually disappeared. the temperatures and length of time it lasted It could only have been water ice that sublimated after being exposed the soil was slightly alkalineand the presence of bacteria-killing perchlorate was not good news for those hoping for Martian life. Phoenix operated for two months longer than planned before the Reunion, the winter completely shading its solar panels, while the planet still had underground deposits of Ice, very little remained on the surface, but it was now understood that many of the Red Planet's features had been sculpted by samples of running water analyzed across the planet. planet claim that water and nothing else had caused these changes in the Martian landscape Mars had once looked more like Earth, but it had lost its surface water and most of its atmosphere and the question of life remained: could have emerged in a warmer, wetter past?

Could it still be present beneath the surface? The next mission to Mars would be NASA's most ambitious yet known as Curiosity. The car-sized Rover would be powered by a nuclear battery that would make it immune to the dust problems experienced by the Spirit and Opportunity Seven Six Curiosity was launched. in an atlas 5 of Cape Canaveral in November 2011. Why the main engines start at zero and take off in mid-2012 entered the Martian atmosphere in the direction of Gale Crater. The jet propulsion laboratory closely monitored the entry, but had no control over events in Mars' thin atmosphere. The parachute could only slow the heavy craft to about 200 miles per hour as it approached the surface.

The Rover's descent stage came off the AeroShell and the rockets activated. At this stage, radar guided the lander to the surface and a small camera recorded images of the terrain. Under the Rover, the next curiosity was lowered on a leash. Below the descent stage, this sky crane technique was used to prevent too much swirling dust, exposing the Rover to unnecessary dangers. Everything had worked exactly as it was supposed to and the American engineers were relieved to talk about the landing. had been the most accurate before Curiosity could start working, its computer went through a checklist to make sure all systems were working properly, a day passed before the Rover deployed its camera.

Communications mast and antennas. Gale Crater is believed to be three and a half billion years old and its sediments were deposited first by water and then by wind. NASA Now has a sophisticated mobile science laboratory on Mars connected to Earth via the most advanced communications link, courtesy of the Mars Reconnaissance Orbiter. The Rover's main goal is to discover whether conditions suitable for life ever existed or still exist on Mars. It is also collecting detailed information on the current conditions on the Red Planet, in particular the radiation levels that will have an impact on the proposed manned missions, thank you.

Curiosity has analyzed dust from several holes it drilled, revealing sulfur, nitrogen, hydrogen, oxygen, phosphorus and carbon, all elements essential for life in its six years. On the surface of Mars, Curiosity has traveled about 20 kilometers, but the driving is taking its toll. He routinely sends a series of self-portraits, mainly for diagnostic reasons. Its wheels have suffered serious damage, which will no doubt lead to design changes for future Rovers. Your computers. They are also causing problems, but a new set of missions are scheduled to arrive at Mars in 2020 that will continue to profile the planet. There is one aspect of the Martian environment that has never been investigated but is about to be addressed.

The Mars Insight probe has been the target. on the planetia Elysium plane near the equator to spend two years investigating the planet's interior, it made a flawless landing in November 2018. After deploying its solar panel, it spent weeks selecting a suitable location to deploy a seismometer on the surface to monitor the Mars earthquakes. It is clear that Mars had a warm and wet past, but it is cold and very dry. Now knowing the geological activity of the planet will help us know why Mars changed the internal probe and also installed a thermal sensor on the surface to collect data on the heat flow from the planet's core.

By understanding the processes within Mars we can learn how the geological histories of Mars and Earth began to diverge. The ringed planet Saturn is more than 100 times the mass of Earth. Its metallic core lies beneath 80,000 kilometers of liquid hydrogen and helium. It is called a gas giant. Saturn. It is orbited by at least 62 moons, each of which is unique, some with complex and dynamic environments. Our only detailed examination of the Saturnian system ended in 2017, when the Cassini probe intentionally crashed into the planet's dense atmosphere to protect against accidental contamination of the moons. Thanks seen from Saturn's rings are visible, but not in 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 the only one to have rings in the early days of space research? Saturn was too far away. Conventional rockets could barely reach Mars 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 the

planets

' gravitational assistance. It would only be possible with the technology of the day when an ambitious new mission began to take shape, it was called The Grand Tour.

Two probes that were far ahead of anything that had been attempted so far would be part of the Mariner series because no spacecraft had been sent. The Beyond Mars mission planners felt it would be prudent to send two rudimentary Advance probes to Jupiter and Saturn to test the deep space environment. Researchers did not even know if it was possible to cross the asteroid belt between Mars and Jupiter in 1972. Pioneer 10 was launched towards Jupiter and a twin the following year. Pioneer 11 was sent to Saturn and both spacecraft passed by Jupiter and discovered that the electron radiation there was 10,000 times stronger than on Earth.

This came as a surprise to NASA engineers who had to modify the most sophisticated spacecraft they were preparing for the Grand Tour. The morning probes that were built at NASA's Jet Propulsion Laboratory were part of a program known as Mariner Jupiter Saturn, but soon changed to the Voyager program, they were launched 16 days apart in late 1977. While Pioneer 10 was headed toward interstellar space and Pioneer 11 was still two years away from Saturn in 1979 when Pioneer 11 approached the ringed planet and began sending back images much clearer than anything seen before of a new ring. The F ring was observed for the first time as the spacecraft flew over Saturn passing beneath the rings.

The mission planners. They were unsure how widely the ring particles would spread if there was a threat to the spacecraft. They were willing to sacrifice Pioneer 11 to get a clear idea of ​​the environment they would encounter with the next Voyager spacecraft. The probe safely passed the ring and continued beyond Saturn. Interstellar space NASA received its last communication from the Probe on November 24, 1995. The subsequent Voyager 1 and 2 probes were very robust, designed to survive during a very long journey and with much greater technical capacity than the pioneers that at the end of 1980 Voyager 1 approached. Saturn, although its high-resolution polarimeter had failed, 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 were able to see how the rings moved. The uneven features within the rings were called radii. They are transient and are believed to be particles lifted by an electrostatic charge after such a long preparation. Information was now arriving at JPL at such a rapid rate that planetary scientists were overwhelmed. The moons of Saturn were of great interest. Voyager 1's path had been chosen because it would take it close to Titan, the second largest moon in the Solar System and the only one with an atmosphere, but the images were disappointing because the thick atmosphere of methane and nitrogen was impenetrable.

Voyager 1 was now spinning above the solar system on a trajectory that would take it into interstellar space while looking toward Saturn. He captured one last image from a unique angle. Nearly 10 months passed before Voyager 2 approached Saturn. Its different trajectory meant it could continue toward Uranus and then Neptune. His high-definition camera was still. Planetary and working researchers were hoping for detailed images of the Rings, and they were not disappointed. The different densities and spaces within the Rings were more complex than anyone had expected. The Rings are named after the letters of the alphabet. In the order in which they were discovered, it became evident that The rings have changed since Voyager 1 saw them, although they extend between seven thousand and eighty thousand kilometers above Saturn's equator, their average thickness is only 30 meters, the spacecraft also sent back photographs of the moon Enceladus, of which its cracked and unpackaged surface was made. ice beneath which there is an ocean ultimately Voyager 2 left Saturn unable to enter orbit It sped towards Uranus it would be 23 years before another probe would visit it and the launch of the Cassini spacecraft to Saturn was launched in 1997 Cassini was a collaboration between NASA and the European space agency and the Italian space agency would take more than six years to reach Saturn Cassini was the largest and 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 to their high profit.

The antenna was used to transmit high-speed data to Earth, but in what is called a ram maneuver, it was sometimes used as a shield to protect the spacecraft from debris impact, especially when it crossed the plane of the rings. Saturn. On July 1, 2004, it fired its engine to enter orbit around Saturn. It was designed not to fail. In addition, its main engine was a backup in case the primary engine failed. It had 16 monopropellant thrusters, eight main and eight more also as backups. Jet propulsion laboratory engineers couldn't know what was happening; the delay and Cassini's disappearance behind Saturn meant that much of the telemetry was recorded for later playback on Earth.

Engine operation lasted 106 minutes. Cassini was the first probe to employ a solid-state recorder unlike the previous Voyager. spacecraft that recorded data on a mechanical recorder Cassini's first orbit followed a highly elliptical path that would take it past the moon Titan. This was important for two reasons: its gravity would be necessary to modify Cassini's course so that Saturn and its other moons could be observed. From different perspectives, secondly, Titan with its dense atmosphere was considered an area of ​​great 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 several weeks over a 20-day period. Huygens drifted for 4 million kilometers and transmitted data to the orbiting Cassini, which would then transmit it to Earth three days after separation. Cassini made a Course Correction that would prevent it from colliding with Titan when high temperatures reached Titan's atmosphere. Cassini was approaching for its third approach to the Moon ready to receive signals from the foreign lander, sampled the atmosphere and recorded images of the landscape beneath the clouds revealed at low altitude.

Hills and channels cut by the flowing liquid there were few impact craters and those that existed were heavily eroded it was the first landing on a body in the outer solar system the images from the surface showed eroded rocks made of water ice which surprised All was that Titan is a geologically active world where liquid ethane and methane instead of water have carved the features while Cassini continued to circle Titan used radar to map the moon's surface confirming the widespread distribution of hydrocarbon lakes. the probe discovered that rain fell on Titan but it was a mixture of liquid ethane and methane the moon has climate and other erosive forces similar to those of Earth but the chemistry is radically different interesting the small moon Enceladus drew attention to itself as the whitest and most reflective body in the solar system, its surface shows craters in the north but the southIt has giant cracks known as tiger stripes on Cassini's first loop that passed by Enceladus.

The magnetometer team noticed a strange deviation in Saturn's magnetic field, as if the small Moon had an atmosphere. During its second pass, the team noticed the same phenomenon they called for for the next Enceladus crossing would 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's stripes. It contained common salt in total. Cassini made 24 descents on Enceladus with the closest flight. Just 25 kilometers above the surface, each of the probe's instruments collected different evidence about jets of water expelled through the moon's southern crevices on Mars.

Rovers have been combing the surface for traces of life, but Enceladus was boasting notable signs that gravitational analysis revealed. a liquid ocean beneath the ice and infrared detectors saw heat emanating from the strange cracks and salt. The scientific 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 effect. ocean, then you have water, we also know that organic substances are coming out because they were measured directly in both the gas and the particles. We also know that there is a source of energy.

The South Pole was hotter than the rest of Enceladus and then evidence was found that deep in its hydrothermal vents on Enceladus' seafloor, these hydrothermal vents would supply the heat and nutrients that could possibly support life with a diameter of 500 kilometers. Enceladus is too small to support a hot core through gravitational radioactive decay. Pressure from Saturn explains part of the warming, but the source of the high temperatures detected remains a mystery, but not only is there liquid water below the surface, there is also organic material, there is a heat source and you know when, when people get excited about the potential of life.

In other parts of the solar system there are four things you need, you need a heat source, you need liquid water, you need organic material and you need those three things to remain stable over a period of time so that life can form Enceladus. We have three We are not sure about the stability over time, but in the Earth's deep oceans hydrothermal vents provide the heat and nutrition to sustain life, they may even have been important for the origins of life, planetary biologists are speculating that the environment in Enceladus's oceans may be the most likely place in the solar system to find some type of extraterrestrial life.

It took a while for Cassini to be in a position where the Sun's backlight allowed the imaging team to capture images of the plumes using a similar technique. The team took this photograph 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 the result of Enceladus' plumes and is constantly replenished by saltwater eruptions. Saying that Saturn has 62 moons is misleading. A particle within the ring system could be considered a moon. There are large inner moons and large outer moons.

There are the Shepherds who shape the Rings. There are coorbitants that swap orbits and there are even moons orbiting other moons that are unique during the Voyager missions. Interest in the moons arose as an afterthought, but a close examination of the moons was planned for Cassini from the beginning. The orbit of Iapetus Saturn Beyond Titan was first observed in 1671 by Giovanni Cassini. He could see it as a POINT of light west of Saturn, but I couldn't see it when it should have been east. It has a bright side and a dark side because the Moon is tidally locked to Saturn.

It is always the dark side that leads as one orbits. The theory suggests that it sweeps away debris thrown up from Phoebe by a more distant Moon. Another feature of Iapetos has scientists baffled. A ridge along the equator extends more than half the way across the moon, is twice as tall as the highest mountain on Earth, and the Iapitosa ridge is only 1,500 kilometers wide, giving Iapitus the appearance of a nut Very precisely targeted bursts from Cassini's main engine allowed mission engineers to modify the probe's circular orbits so that mission specialists could focus on multiple moons, different areas of the ring system, or different parts of the ring system itself.

Saturn with gravitational assistance from the moons, particularly Titan, mission control were able to conserve fuel. The Cassini probe performed so well that it received two mission extensions, but the fuel couldn't last forever. Planners had scheduled the most dangerous part of Cassini's mission for its final year at Saturn in late 2016. Cassini began a series of polar orbits that would take it near the outer edge of the rings in what mission specialists called grazing. In the rings, the spacecraft's mass spectrometer and its cosmic dust analyzer would take samples of particles and gases as it crossed the plane of the rings on orbit 251, on its first pass over Saturn's north pole, recorded the peculiar storm hexagonal shape that was first hinted at in the Travels.

More than twice the diameter of the Earth, it 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 clouds and green indicating higher clouds. The winds at its edge blow at 540 kilometers per hour. Part of Cassini's dual-technique magnetometer had stopped working at the beginning of the mission without it, the spacecraft had to make maneuvers from time to time to calibrate the instrument, the spacecraft would make 20 ring-grazing orbits with the work of its instruments mapped in the second as the sun was almost directly behind the rings Cassini looked for dust clouds something is reducing the ring particles to fine dust Cassini made a series of radio occultation observations with the rings between the spacecraft and the Three radio signals of different wavelengths were simultaneously transmitted to Earth, 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, green denotes particles smaller than five centimeters, and blue for particles smaller than one inch. centimeter. The complex gravitational interaction between Saturn, its rings and its moons generates spaces in very particular places. Before Cassini arrived, only 18 moons were known; that number has increased to 62. Prometheus acts as a shepherd Moon that limits the inner edge of Saturn's orbit along with Pandora, which it orbits. Outside the fizz the two moons keep the ring tightly confined. In April 2017, Cassini's orbit was changed for the final phase of its mission.

The probe would now loop inside the rings, although it would ultimately mean burning up in Saturn's atmosphere. the information gathered from such close proximity Because Saturn and its rings would give a more complete picture of the gas giant, it was decided that intentionally destroying Cassini was preferable to leaving it adrift without fuel, possibly contaminating one of the moons. Cassini's sensors began picking up a stream of ring particles falling on Saturn some time ago. A continuous shower of ice and dust particles are pulled toward the planet's equator by gravity or, at higher latitudes, charged ring particles spiral in along magnetic field lines.

Every second, ten thousand kilograms of ring rain fall to the surface. At this rate, the rings will disappear completely. 100 million years ago, researchers were surprised to discover an electrical current flowing between the inner D ring and the upper atmosphere. Toward the end of Cassini's close pass to Saturn, the spacecraft began to image the upper edge of the atmosphere. All information had been retrieved from the data recorders. It was now beamed directly back to Earth, but relied on the spacecraft's thrusters to keep Cassini from falling by keeping its high-gain antenna pointed precisely. The probe's final job was to sample the atmosphere and measure the shift of Saturn's magnetic axis.

Mission Control there was no longer control over the Engineers could monitor the signals sent from Saturn 84 minutes earlier within the next 45 seconds, so the spacecraft will take years to process the data obtained from Cassini. There are no future missions scheduled to Saturn yet. Thank you. Jupiter is our Solar System. The largest planet has 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. Recent images from a new probe that has flown over Jupiter's poles reveal a different foreign planet.

The ancient Romans knew Jupiter as the celestial representation of the king of the gods. In 1610, Galileo using his newly improved telescope saw the moons of Jupiter and could Seeing that they orbited the planet was evidence that not everything revolved around the Earth as the church had declared. Better telescopes improved our view of Jupiter. It was not until 1964 that Gary Flandro, a graduate student working part-time at JPL, NASA realized there was a way to get a clearer view of Jupiter by plotting the positions of the outer planets and realized that a rare alignment would allow a spacecraft launched in 1977 to visit Jupiter, Saturn, Uranus and Neptune.

NASA seized the opportunity and began work on a sister ship 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 information about the environment toward Jupiter. In March 1972, it was the first spacecraft through the asteroid belt. that was between Mars and Jupiter and because it was the first probe on a trajectory that would take it outside the solar system it carried a plaque identifying its origin in December 1973. Pioneer 10 sent back images of Jupiter clearer than anything that had been seen Before approaching Jupiter, it found levels of iron radiation ten thousand times more intense than the radiation belts surrounding the Earth.

As the probe skimmed the giant planet, it gained speed as it left Earth. Pioneer 10 was moving at 51,000 kilometers per hour as it left Jupiter. It had more than doubled its speed. This gravitational effect made the Grand Tour possible. The newly renamed Grand Tour spacecraft Voyager 1 and 2 were due to be transferred to Cape Canaveral for launch integration when news of Jupiter's extreme radiation environment came in, as electron radiation at Jupiter had generated false orders within Pioneer 10. With travel much more sophisticated, this presented problems, local supermarkets were stripped of their stock. of kitchen aluminum foil that was later used to protect critical cables, without this last-minute alteration electrical pressures of up to 40,000 volts would have been induced in Voyager's subsystems as the spacecraft passed by Jupiter.

Voyager 2 was launched in August 1977. Its trajectory meant it could visit Jupiter, Saturn, Uranus and the Neptune system. Voyager 1 left 16 days later. Its different, faster trajectory only allowed for flybys of Jupiter and Saturn and several large moons at the time. that the Voyager spacecraft was the most sophisticated probe launched because they had to operate at enormous distances from the Sun. The solar panels could not be used as a power source. They were equipped with radioisotope thermoelectric generators that used the heat from the decay of plutonium-238 to generate power When Voyager 1 approached Jupiter in January 1979 it began sending back image sequences showing a complex and dynamic planet the planet's giant red spot was revealed as a large rotating storm in 1665 Giovanni Cassini described a permanent spot on Jupiter which was regularly observed until the 18th century, it was not until the late 19th century that Jupiter's spot was described as red and it is not clear whether historical observations of Jupiter's spot refer to the same characteristic or to a phenomenon that manifests itself regularly in Jupiter's atmosphere.

Voyager 1 made its closest approach in early March 1979. As the probe approached Jupiter, activity at NASA's jet propulsion laboratory became intense - this was the nature of NASA's flyby missions.Voyager, although a long, quiet phase of cruising between the planets followed by brief periods in which the flow of information from the ship overwhelmed the researchers. One of the greatest contributions made by Voyager was the transformation in our understanding of Earth. The Galilean moons that were previously just points of light. Jupiter's four largest moons were distinct and completely different. The first surprise was the inner Moon IO. It has a sulphurous yellow appearance and one particular long exposure revealed a strange column instead of a cold, dead world.

The compression that IO receives from its giant neighbor heats the interior of the moon. The plume was a volcanic eruption that ejected material hundreds of kilometers above the surface in July 1979, three months after Voyager 1 moved past Jupiter. Voyager 2 made its closest approach and was able to examine different moons. closer than its twin Europa was the next surprise: it is highly reflective and has the smoothest surface of any body in the solar system. Closer observation revealed pressure ridges reminiscent of polar ice flows on Earth. Europa is a frozen world with a vast ocean beneath a thick layer of ice. ice crust as IO is heated from within by tidal bending as Voyager 2 moved toward Saturn planetary researchers were left with large amounts of raw data about Jupiter yet to be processed Voyager missions left us with a basic view of the Jovian system , but they had not raised more questions than they could answer, it would be more than 10 years before Jupiter received another visitor from the Earth Mission and the lift-off of Discovery and the Ulysses spacecraft found for the polar regions of the Sun in October 1990 , the space shuttle Discovery lifted the European spacecraft Ulysses into low Earth orbit from there it was boosted on a mission to observe the Sun, but first it would pass by Jupiter.

All planets orbit the Sun in the same direction, in approximately the same plane, this is called the ecliptic and developed from the rotating disk of dust and gas that formed our solar system. The designers of the Ulysses spacecraft wanted to see the Sun from an orbit above its poles. Jupiter's extreme gravitation was used to divert the probe's flight path away from the ecliptic so it could make north-south orbits. in front of the Sun Ulysses was not the only probe that took 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 these probes' flybys of Jupiter. were able to make significant observations as it passed by the giant planet in the clean rooms of the jet propulsion laboratory a new probe Galileo was taking shape it would be the first spacecraft to enter orbit around Jupiter its 4.8 meter antenna was folded like an umbrella only to be deployed when safely en route to Jupiter its overseas launch was scheduled for 1986 remained in storage for years after the space shuttle exploded Challenger was launched aboard the space shuttle Atlantis in October 1989. ignition and liftoff from Atlanta new rules governing shuttle launches meant a change in booster to push Galileo out of Earth orbit the less powerful solid-fuel upper stage now stipulated sent Galileo toward Venus for gravitational assistance the new flight path It meant that Galileo was traveling to a hotter part of the solar system.

It was decided to keep the heat-sensitive antenna coiled until the Loop spacecraft retreated past Earth. Galileo made two close passes over Earth, each time gaining more speed on its first pass. It was in December 1990, more than a year after its launch, a year later when it passed by 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 of storage had caused the lubricant on the tips of the antenna ribs to dissipate. Researchers would rely on Galileo's smaller antenna with data delivered at slower speeds during the cruise to Jupiter.

Galileo found several asteroids, this is Ida, the first asteroid we have known about with its own dactyl Moon in July 1995, when it was still six months away from its closest encounter with Jupiter. Galileo ejected a small probe designed to enter the atmosphere and take samples of its chemical substance. composition the probe lasted one hour in Jupiter's atmosphere the data was transmitted to Galileo and recorded for later transmission to Earth its analysis revealed almost no water vapor, which was unexpected and other elements, particularly helium, were detected in levels much lower than those predicted by the probe. areas of extreme heat and cold, suggesting that heat is being released from the planet's interior just over an hour after transmission ceased since the Galileo probe began its insertion into orbit, burning its engine had to run for 49 minutes to put it into a highly elliptical equatorial orbit, but this orbit would be altered with another burn on its High Point mission.

The designers were well aware of the high radiation environment and the second burn would lift Galileo above the extreme radiation on its closest approach. Galileo's initial orbit eventually approached Ganymede, Jupiter's largest moon. During this orbit, engineers were trying to understand damage to the spacecraft's vital recorder without its high-gain antenna. The recorder was essential for slow playback of data recorded during the brief Close Encounters. It had been stuck in rewind for 15 hours and the tape had degraded. Emitting diodes are key elements in controlling the recorder. The system had acquired radiation defects. The second orbit also passed Ganymede.

Galileo discovered that it is the only moon in the solar system with a significant magnetic field. It also has an ocean sandwiched between two ice sheets. Galileo's orbits would be varied slightly so that it could approach different Jovian moons, but the equatorial orbits needed to reach the moons also took the spacecraft through hot spots in Jupiter's radiation belts. With observations made by the voyages, the moon Europa was of particular interest to Galileo's team. Data from several instruments agreed that a salty moon ocean exists beneath Europa's ice surface. Further examination of the Galileo data sets revealed information about plasma waves and magnetic fields that showed plumes of water vapor were rising from cracks in the surface.

Europa has more water than Earth, making it a possible home for life. It is known to have volcanic activity but Galileo saw tides on the solid surface of the Moon of more than 100 meters. The temperature is generated by this gravitational distortion of i o makes its numerous volcanoes hotter than anything found on Earth during its eight years on Jupiter Galileo completed 35 orbits filling To bring to light our limited picture of the Jovian system, this was never an easy mission. Galileo was a robust spacecraft, but the radiation environment stressed all subsystems and engineers had to constantly find solutions for Galileo's frequent breakdowns.

The instruments showed an increase in noise when close to Jupiter and current. The leaks caused by the radiation caused several reboots of the on-board computer with crucial data loss. Software changes allowed the computer to recognize these resets and recover on its own the learned information that would lead to changes in the way the next spacecraft was designed Jupiter five four three two one power up and liftoff of the Atlas V with Juno en route towards Jupiter in August 2011 Juno began a journey to Jupiter that would last almost five years its mission parameters would be very different from those of Galileo it would ignore the moons and focus exclusively on the Jupiter plateau The design of the spacecraft saw crucial electronic components protected within a thick titanium vault and, instead of a plutonium power source, Juno would rely on solar panels.

The sun's intensity on Jupiter is about five percent of what it is on Earth, so the panels are huge. There is a shortage of plutonium stocks. -238 led to the change in energy sources. Juno followed a circular orbit that took it past Mars before returning to Earth for a gravitational boost that added 14,000 kilometers per hour to its speed and sent it toward Jupiter. Juno approached Jupiter on a path that took it above the planet's north pole, it was intended for a north-south orbit, this would see it pass beneath the severe sections of the planet's radiation belts that extend from the Jupiter's equator, four days before its closest approach.

Mission Control sent a command that initiated the spacecraft's autopilot. On July 4, 2016, Juno initiated an engine burn that would insert it into a 53-day orbit. 48 minutes later, JPL Mission Control received tones verifying that Juno had begun its deceleration maneuver. It was a tense 35-minute wait for the systems engineers. Before confirmation came that Juno had worked exactly as expected, thanks to Juno scientists and engineers, it was a relief that things were going as planned. Do you know that Juno is equipped with a set of instruments capable of penetrating the thick Jupiter cloud that the polar orbit allows? Juno will compile a three-dimensional map of the upper atmosphere, building an image 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 because Juno was planned to only make two 53 14-day orbits and then switch to a series of 14-day orbits that would accelerate the sampling rate. The spacecraft's main engine is powered by hydrazine and nitrogen tetroxide, which ignites spontaneously when they mix. The propellant and oxidizer are expelled by an expanding helium bladder. When Juno was finishing its second orbit, the helium valves were not responding correctly, so it was decided to maintain the original orbit. An orbit emission extension has been granted to allow longer orbits that Juno continues to follow a day after the helium valve problem.

Juno entered safely. mode all instruments went offline and data was lost, appeared to be similar to the difficulties experienced by Galileo, but engineers attributed the problem to a data transfer problem from a specific instrument and the spacecraft remains healthy. Jupiter's axis is tilted only three degrees, making even an oblique view of the poles nearly impossible until Juno arrived. When viewed in the infrared, the researchers saw a complex arrangement of storms at both poles. At the North Pole, a central vortex is surrounded by eight anticyclones. At the South Pole, five anticyclones surround the central storm. Scientists don't understand why all storms spinning in the same direction don't destroy each other on their seventh close pass of Jupiter.

Juno flew directly over the giant red spot. Its microwave radiometer was able to map heat distributions at different levels up to 350 kilometers. The red spot is a giant storm and Juno could see much higher temperatures at deeper levels that could penetrate without geographical features, since on Earth there is nothing on Jupiter against which the storms can dissipate. The Great Red Spot remains firmly at 22 degrees below the Earth. However, it appears to have circled the planet at least 10 times since reliable observations began. Jupiter's magnetosphere is huge. It traps charged particles in bands that extend over long distances. was generated like that of the Earth by the action of the Dynamo the convective movement of an electrically conductive fluid in the depths until now the 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 appear to come from a different mechanism than here on Earth.

By focusing on the composition of the gas giant, researchers hope to gather clues about the conditions in the formation of the solar system, while the Earth has been continually changed. Due to tectonic forces, Jupiter is believed to remain very similar in composition to the cloud of gas and dust from which the solar system formed. 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 focus onEuropa as the most likely place after Earth to host some form of life known as the Europa Clipper.

Scheduled for launch in 2022, like Juno, it will be solar-powered and its elliptical orbit of Jupiter will see it fly over Europe every two weeks. The mission required 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. Thanks, although Europa's ice crust is thought to be at least 19 kilometers thick. Precise measurements are necessary. If thin areas can be found, then future missions will be able to access the ocean below. Concepts for explorers under the ice are being developed and we can expect other missions to focus on other moons like the largest planet.

Jupiter's influence on the rest of the solar system is profound. It has more than twice the mass of all the other planets combined. All the orbits of the other planets are affected by Jupiter's gravitation. To learn about Jupiter, some of the planets Our Solar System has been visited by scientific probes less frequently than others. The outer gas giants Uranus and Neptune are so distant that it is difficult to reach them. Uranus is 20 times farther from the Sun than Earth, while Neptune is 30 times farther away. Both have only been seen up close 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 compensate for the Sun's immense gravitational influence.

The Mariner 10 probe passed by Mercury in 1973 and the Messenger probe entered orbit around Mercury in 2011. Venus presents different problems, although it is our closest and easiest planetary neighbor. For the spacecraft to reach a dense cloud that hides its characteristics and its surface has hellish conditions, the Russian scallops have landed but in the hostile environment they could only survive for minutes. About twice every century, the planet Venus passes between the Earth and the Sun, a so-called transit of Venus was closely observed in 1769. Astronomers realized that careful timing of Venus's passage across the face of the Sun allowed them It would allow us to calculate the distance to the Sun, which in turn would unlock much more precise navigation methods.

In 1961, the Soviet Union launched Venera. 1 the first Venus probe passed by Venus as planned, but Mission Control had lost contact with it overseas the following year NASA launched Marinawanda Venus we are not on trajectory a coding error caused 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 spacecraft designed to go to the Moon. It was the early days of the space race and the United States was desperate to catch up to the Soviet Union. Delivery times were short and the jet propulsion laboratory did not have time to complete its original design in August 1962.

Mariner 2 was launched. The Ranger spacecraft launched towards the Moon had failed. Mariner 2 on its way to Venus was running but its transmissions were weak and due to a launch anomaly, it veered off course after a week, instructions for a complex course correction were transmitted to the spacecraft about an hour later. Mariner then executed the maneuver which involved a roll turn followed by a pitch turn and finally a main engine burned well, but several days later, the ship lost contact with the Sun and Earth, its two attitude reference points. were corrected before Ground Control could diagnose the problem.

The signal strength then increased to its normal level, but a short circuit in a solar panel left it low on power. Although both the United States and the Soviet Union had been sending probes toward the planets, nothing had been successful. Mariner 2 lost several telemetry sensors and began to overheat. It continued to limp toward Venus, but some of the spacecraft's problems were resolving themselves. Mariner 2 was now close enough to the Sun that it could operate effectively with a single solar panel just under 35,000 kilometers above the cloud tops of Venus, it was unable to detect any planetary magnetic field, and it recorded planet-wide temperatures close to 500 degrees Kelvin, clearly landing on the surface would present problems first true success in space finally doing something the Soviets had not done Mariner 2 was the first successful interplanetary probe and in California, the headquarters of JPL, they celebrated the next great advances in The exploration of Venus were carried out by the Soviet Union, the target of the Venera series.

The landing on the surface of Venus was designed taking into account that not only were the surface temperatures high enough to melt lead, but the atmospheric pressure was many times greater than 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 transport ship with instruments used during the cruise phase to Venus and a spherical lander that could communicate independently after entering the atmosphere. Venera 4's parachute opened and sent data for 93 minutes, but still stopped 28 kilometers above the surface. its electronics hadn't been overwhelmed by the heat, it had simply run out of power.

Extrapolations of their final measurements showed a surface temperature of 500 degrees Celsius and a pressure of 75 atmospheres, much higher than anyone expected. The Venera program strengthened its landers and installed smaller vehicles. Parachutes to reduce descent time launched in January 1969. Venera 5 and 6 learned more about the chemical composition of the atmosphere, but neither remained operational on the surface. The Venera series continued to refine the technology and make incremental improvements to mission duration, increasing knowledge about Venus. In 1975 Venera 9 was launched. It was a new design consisting of a combination of the Orbiter Lander with the Orbiter capable of acting as a relay station for signals transmitted from the surface.

Four months after launch, the Orbiter and Lander enclosed in a separate spherical shell entered. atmosphere two days later, as the mother ship became the first probe to enter orbit around Venus by photographing parts of the surface in ultraviolet, the new lander had a protective ring that could replace a parachute during the final stages of the descent through the dense atmosphere. Thank you. Venera 9 transmitted the first black and white photographs from the surface, although a design error meant that a second camera could not eject its lens cap three days later and a Venera 10 sister ship landed 2,000 kilometers away.

It also took photographs, but the same design error left a The lens cap was stuck in place. Both landers had been precooled while still in space, and circulating coolant kept the craft operating on the scorching surface for more than an hour. In 1983, two more Venera spacecraft arrived at Venus equipped with synthetic aperture radar. first serious attempt to map the surface below the cloud cover for eight months, they mapped from the North Pole to 30 degrees north Demarest 10 9 8 7 6. NASA had taken a minor role in early explorations of Venus, but in 1989 The space shuttle Atlantis took off carrying the Magellan probe.

Magellan was heading to Venus like the Venera ship before. Magellan would use radar to map the planet's surface. It was the first interplanetary spacecraft launched from the space shuttle after a 15-month cruise. 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 to map the images it transmitted were still the highest resolution images that We have images of low-lying volcanic blebs and lava channels emerging from the surface of Venus, which were evidence of an extremely active surface.

The thick atmosphere has prevented all but the largest meteors from reaching the Venusian floor, and few impact craters were visible. , but evidence of tectonic plates sculpting 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 features of Earth's surface this This is not the case. A new naked image of Venus emerged. The surface appears to have been completely remade around 500 million years ago, although volcanoes and lava channels are common features of Venus. Magellan could not find evidence that there is still volcanic activity. on the planet in 2006, the Venus Express of the European space agency entered orbit around Venus.

Its objective was the long-term analysis of the planet's atmosphere. During its eight-year mission, it recorded a sharp increase in sulfur dioxide from the planet. atmosphere, this could be due to changes in wind patterns, but it could also be a sign of volcanic activity. The researchers also saw increases in infrared radiation coming from three different volcanic locations. More circumstantial evidence of current volcanic activity. Finally, the infrared equipment. we saw short-term temperature changes that fluctuated over just a few days it seems volcanoes may still be active on Venus the mission ended in 2015 with a series of drops in the upper atmosphere that verified unexpected ripples in the mesosphere very little along the way Exploration of Venus has been done from Venus Express, although there are plans drawn up for future missions to Venus, nothing has been funded so far, but many missions still pass close to Venus to use its gravitation to alter their flight paths in 1974.

Mariner 10 was the first spacecraft to do so. use the gravitational slingshot effect on its way to Mercury Italian mathematician Giuseppe Colombo devised the maneuver as a way to save fuel and pass by Mercury not once but several times the technique is now common ten days after launch Mariner 10 executed instructions for a Routine course correction, this seemed to go well, but after the burn, when the ship attempted to reorient itself, there was a problem. Mariner 10 knew where it was pointing because its tracking sensor could lock on to the Canopus star, but a flake of paint that had come from the spacecraft was confusing the system.

An automated backup procedure found Canopus again but the peeling paint was a problem for the rest of the mission to reach Mercury a spacecraft must approach the Sun and its immense gravity presents a problem trips to outer planets are constantly slowed by solar gravity but with the inner planets a spacecraft constantly accelerates Mariner 10 used gravity of Venus to slow down and approached Mercury at an acute angle Mariner 10 did not have enough fuel to enter orbit around Mercury but its sun-centered trajectory allowed the probe to approach three passes. Its first pass revealed a planet resembling a moon with a surface full of craters although Mercury is the smallest planet it is the most dense it has a large core rich in iron prominent scarps were seen here The scarp of discovery passes through two craters it is believed to fall three kilometers that these cliffs are the result from cooling and core shrinkage Mariner 10 continued to suffer technical problems its recorder continued to jam there were restrictions on data transmission rates and limited attitude control meant flight engineers were using solar pressure on the high-gain antenna and panels solar cells to compensate, but the mission continued.

Mariner 10 was only able to map about 45% of Mercury's surface when the same hemisphere faced the Sun during each of its passes. Mariner 10 discovered a very thin atmosphere of mostly helium several months after its third and final pass of Mercury it ran out of fuel it still orbits the sun main engine started two one and more than 30 years passed before the next mission was launched to Mercury in 2004 messenger was designed to enter orbit around Mercury, which presented a number of design limitations. It featured a large woven ceramic sunshield, but did not have a satellite dish. It would depend on a phased array that could be electronically targeted after a year in space.

The messenger was back on Earth using its gravitation to modify its orbit even though it wasn't. a large spaceship had a powerfulengine for course corrections and orbit insertion continued to pass Venus twice to lose speed as it approached the Sun three and a half years after the launch of the messenger it approached Mercury but this was not the end of its journey the The probe made two more passes over Mercury before finally entering orbit after nearly seven years in space. Mission engineers had the additional problem of always requiring the probe's sunshade to point toward the Sun because it was in orbit that the messenger was able to complete the mapping it had begun. by Mariner 10.

The planet's dominant feature is the Caloris Basin, an ancient crater more than 1,500 kilometers wide. Mariner 10 saw part of the area, but the rest had been in darkness. This map of the south polar region uses colors 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 underway. a Mercury depi Colombo is named after the designer of the Mariner 10 trajectory.

It is a joint effort between the Japanese space agency and the European Space Agency. It will take seven years to reach Mercury. The Voyager 2 spacecraft is the only probe that has come close. much to both The outer ice giants Uranus and Neptune were launched in 1977 with its twin Voyager 1. It was able to take advantage of a rare alignment of the four outer planets that allowed it to make close observations of each in 1986. Voyager approached Uranus in the distant past. have been hit by another massive body that shifted its axis to one side Uranus has an East pole and a West pole and during half of its orbit one side sees the sun continuously while the other remains in darkness it has rings that follow its northern equator -south Voyager 2 discovered 11 Voyager's images of new moons and a misaligned magnetic field showed Uranus as a featureless, nondescript planet, but this was due to 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 of Uranus. The largest moon, Miranda, was observed in detail for the first time. Its surface is so chaotic that researchers thought it must have been destroyed by some cosmic impact and the fragments reformed. Tectonic forces initiated by Uranus's gravitation are now believed to be responsible for the confusing appearance of the moon Zoyager 2 left Uranus' backlighting from the Sun revealing two new rings surrounding the planet. The spacecraft was now heading towards Neptune. The last planet in the Solar System in the three years it would take to get there.

Engineers began preparing for unique challenges. Neptune is 30 times larger. Further from the Sun than the Earth and the light intensity is one-thousandth of what is here for photography, long exposures would need to be taken, but Voyager 2 was traveling so fast that the images would shoot out without special preparation. Engineers calculated how much the ship would have to turn. While exposures were being made to compensate for the probe's movement in June 1989, Voyager 2 began sending distant images of Neptune around the world, people had realized that the data sent to Earth by this spacecraft were transforming our understanding of the solar system abroad, this was before the Internet age researchers are in the jet propulsion laboratory clustered around televisions to watch as data and images appear line by line and it is a planet more conventional than Uranus.

Excel's tilt is 30 degrees and it rotates in the same direction as Earth, while Neptune is a little heavier. that its fellow ice giant Uranus has a slightly smaller diameter and is farther 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 on Neptune In excess At 2,000 kilometers per hour, the fastest in the solar system, there were cirrus clouds in the atmosphere and the probe recorded images of a Great Dark Spot similar to Jupiter's Great Red Spot. It was an anticyclone in the southern hemisphere as large as the Earth.

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 position. orbit indicating that it was not formed at the same time as the planet but that it had been captured when Voyager 2 moved past the planets its cameras were turned off to save energy both travelers continue far from the solar system measuring the influence of the solar wind This remains the only mission to the ice giants.

An Atlas V was launched on January 19, 2006. It was a very powerful rocket with an unusually small payload. New Horizons left Earth's orbit faster than any other probe. It was headed to the Kuiper Belt outside. edge of the solar system, in particular Pluto, in just over a year, New Horizons reached Jupiter, where it received a gravitational assist that shaved three years off its flight time to Pluto. After passing by Jupiter, the spacecraft went into hibernation by simply sending a general transmission once. In one week, it took New Horizons more than nine years to reach Pluto since its departure.

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 clarify its orbit the characteristics of Pluto surprised everyone here it was a living planet formed 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 the icy surface of the moon largest on Pluto today. deep canyons and some evidence suggests it has ice volcanoes Karen is about half the size of Pluto and the two orbit each other since Pluto Karen would appear motionless in the sky as the New Horizons probe moved away from Pluto into deep space the slow In the process of transmitting the recorded data to Earth at these distances, the signals take four and a half hours to reach Earth and the data arrives at one kilobit per second.

It took 469 days for all the information from Pluto to be received on Earth in early 2019. New Horizons surpassed the Neptunian object Trends Ultima Tooley and with a mission extension continues to explore the far reaches of the solar system Earth is our home our environment natural results from complex relationships between the Sun, the oceans and the atmosphere, polar ice and 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 have observed. Earth's environment has allowed life to arise and life has changed the planet as far as we know Earth is the only planet in the universe that has given rise to life The Orion Nebula is a vast cloud of gas and dust in The Orion constellation is a place where new stars are created as part of the nebula condenses it separates into groups as each group contracts under its own gravitation it begins to spin and flattens into a disk they are called Protoplanetary disks or proplets at the center of a proclide, as the molecules squeeze together, a fusion reaction begins and a star ignites some proclides that occur near a set stellar brightness. brightly under the influence of their neighbor, while this makes them easier to observe.

Bright gas and dust are being stripped by stellar winds from adjacent stars. The dark thrusters are only observable as silhouettes that maintain their surrounding ring of gas and dust as the system matures. Stellar debris will form a planetary system. The Hubble Space Telescope has recorded numerous examples of this process, enough for astronomers to understand that planet formation is common. This is how our Sun began its life 4.6 billion years ago, but the planets would take longer to form. Small grains emerged within the disk and began to accumulate, forming planetesimals. The larger a group became, the stronger its gravitational pull, which in turn led to faster growth.

An early version of Jupiter would have been the first to completely merge by clearing its orbit around a core of heavy metal and rock. Jupiter's atmosphere, composed primarily 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 that young Jupiter would have begun a path toward the sun, dragging asteroids and comets with it, but Jupiter's internal trajectory was reversed when it was pushed into an orbital resonance with the emerging Saturn, not all objects that formed in the system.

Due to the stronger gravitation or even captured by becoming a moon, it is believed that there were up to 20 smaller planets orbiting in the inner solar system at from which the four remaining terrestrial planets were formed. At the time, collisions in the developing planetary system were common and evidence from the Apollo moon rocks suggests that an impact between the early Earth and an ancestor of our moon was important in the evolution of our planet, Earth has a larger iron core than expected and gravitational analysis of the Moon suggests that its core is lighter than expected. A collision between the bodies would explain the loss of much of its heavy material by the Moon to the more massive Earth. , was an indirect hit that caused the Earth to spin rapidly with a five-hour day the Moon we know coalesced from 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 on the Earth's rotation is significant over long periods the Earth's axis will vary. up to a degree without the influence of the moon this variation could be up to 85 degrees with drastic implications for climate stability the planets cleared the debris of the early solar system in one period required intense bombardments the emerging Earth was dotted with asteroids and comets that They carried the water needed for life as tectonic forces erased the Earth's bombing scars.

The moon that endured the same tribulations is still covered in craters as chaos in the developing solar system settled the young. Earth was in a unique position, the Earth's distance from the Sun was perfect for an abundance of water to exist on the planet in liquid form. As the Moon had moved away, the planet's rapid rotation had slowed and the Sun's heat was shared evenly across the entire surface. The Earth's large metallic core combined with the planet's rotation meant that a magnetic field extended around the planet deflecting the charged solar wind and protecting the surface from the extremes of solar radiation in a hostile Universe Earth was an exceptionally benign environment.

The geological record shows that around 2.7 billion years ago oxygen began to appear in the atmosphere. Western Australia's vast iron ore regions were formed when iron in the oceans reacted with the new abundance of oxygen to form iron oxide. Simple plant life used sunlight and carbon dioxide to live and produced highly reactive oxygen as a waste product, this allowed more complex life to emerge, built an intricate network of interrelated plants and animals, completely transformed the planet, changing in the atmosphere had other dramatic consequences, oxygen drastically eliminated much of the highly insulating gases from the air. Cooling the Earth began a sequence of ice ages, although there is abundant evidence showing planetary glaciation interrupted by warm periods.

The factors that trigger these cycles are complex fold lines. Clues to the movement of continents that lead to rerouting of ocean currents. The effect of volcanic activity. on the atmosphere and changes in the direction of the Earth's axis with respect to our planet's elliptical orbit around the Sun, all factors that contribute to long-term fluctuations in the Earth's climate. The analysis of ice cores deposited in Antarctica or Greenland is aaccurate way to see how the composition of the atmosphere has changed over the previous 800,000 years air bubbles trapped between snowflakes before becoming rigidly trapped as the snow turns to ice can be accurately sampled one thing It is clear that carbon dioxide peaks at about 270 parts per million during warm periods and falls to about 170 parts per million when glaciation is at its maximum, but from this data it is difficult to know whether the additional CO2 causes the warming or whether warming leads to additional CO2 In 1958 Dave Keeling, working for the Scripps Institute, began recording precise levels of atmospheric CO2 at the Maunaloa Observatory in Hawaii was the beginning of a unique record known as Keeling curves.

The Keeling plot revealed a seasonal variation corresponding to spring and summer in the northern hemisphere, where land mass and vegetation cover are greatest during the northern spring and even During the summer, CO2 levels fell due to the increase in photosynthesis in the 1970s, a disturbing trend had emerged. CO2 levels were on a steady rise at first, there was uncertainty over the implications that additional CO2 could trap more heat, leading to a warming effect known as the greenhouse effect. But some scientists worried that aerosol pollution could dim the levels of sunlight reaching the planet, causing the environment to cool as the decades passed.

Different pieces of evidence were collected. Drilling cores from the ocean floor revealed that ice ages had been triggered by Milankovic cycles. The variations between the Earth's tilt and its elliptical orbit, although these effects were minor, the correlation was obvious. If such a small nudge could alter the climate, perhaps changes in CO2 could too. Scientists were realizing how poorly they understood planet Earth. At the beginning of the space age, American scientists were interested in making weather observations from orbit, launched in 1960. Tyros 1 was the first weather satellite. It was equipped with two television cameras that periodically transmitted images of global cloud patterns.

It provided meteorologists with a unique view. Improved versions followed because these early satellites were in low, highly inclined Earth orbits. The data collected covered the entire planet and was shared around the world. 1873 Nations had been cooperating in weather prediction through the international meteorological organization which in 1951 became the World Meteorological Organization. organization an arm of the United Nations based in Geneva with a UN resolution calling for international cooperation in the peaceful uses of outer space the weather satellites of different nations were soon coordinated for the benefit of all humanity in 1964 the program began A series of seven satellites including a more sophisticated set of sensors Nimbus was a testbed for new technologies and collected data over different areas along with cloud patterns, information about the atmosphere and sea ice.

This was the pre-digital era and all electronic image data was recorded and stored. on 70 millimeter film little thought was given to establishing an archive for future reference the program was an early example of Earth observation rather than simply a group of weather satellites a meteorologist began to view the planet as a complex, interconnected system today Today there is a fleet of satellites operating that monitors the atmosphere, oceans, ice, land and biosphere. It is now understood that ice, particularly sea ice, plays an important role in the Earth's climate system. Polar ice slowly flows towards the coasts where it melts providing a source of cold water that drives the ocean currents.

Ocean currents are 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 through clouds, keeping the land moist and able to support vegetation and plant life in both oceans. and the atmosphere removes CO2 from the air and replenishes atmospheric oxygen both the ice known as the cryosphere and the clouds reflect a proportion of the sun's energy into space the extent of the ice and the cloud cover are important factors in the energy budget of the Earth As ice melts, it exposes ocean or rock, which absorbs more solar energy.

Similarly, cloud cover or its absence will have an effect on the land or sea beneath the vegetation. It is also an important climate factor, since land plants pump enormous amounts of water vapor into the atmosphere. but things are changing Humanity simply through the weight of numbers is influencing key elements of the planet's climate system In 50 years the human population of Earth has increased from just over 3.5 billion to 7.7 thousand millions today or people need more resources and although there have been revolutions in agriculture and technology, the Earth's reserves are not unlimited. In 1979 Europe began to launch spacecraft and while the new Earth observation satellites were revealing changes scientists were reluctant to draw conclusions about long-term trends they understood that there was some variability in the planet's climate cycle and although climate science was aware of the constant increase in atmospheric CO2 revealed by the Keeling curve, researchers were looking for additional solid evidence that change caused by human activity had been occurring since 1913.

Spectroscopy had revealed that an ozone layer in the stratosphere blocked harmful ultraviolet sunlight. reaching Earth 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 evidence of the polar vortex above. The southern continent concentrates CFCs in the stratosphere. Pearly clouds in polar skies contain ice crystals that, in combination with ultraviolet radiation, separate chlorine from the CFC molecule. Each chlorine atom can break down more than one hundred thousand ozone molecules.

A large area centered over Antarctica showed almost no ozone known as the ozone hole. The United Nations began talks aimed at limiting the production of CFCs and in 1989 an international treaty known as the Montreal Protocol limited the production of CFCs. CFC and ultimately resulted in a 10-year phase-out. of CFC production all countries signed the agreement and the Montreal protocol is considered a model of international cooperation in the 1980s an upward trend in global temperature averages became evident and a scientific consensus emerged that fuel burning fossils was altering the balance of gases in the atmosphere most of our planet's fresh water is locked in the polar 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 sea surface.

The ice grows and shrinks with the seasons. Seasonal sea ice also borders Greenland and Antarctica. Ice shelves are a third manifestation of polar ice. They are thick sheets of ice that extend into the ocean from the mouths of glaciers. Icebergs periodically break off from these regions. These areas. They 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 through the Grace satellites which were recently replaced by a similar pair of Grace Follow On satellites. . They both follow the same orbit. and minimal changes in the Earth's gravitational field will cause them to change speed with a variation in the distance between them.

This data is measured precisely, allowing researchers to record changes due to variations in groundwater or ice thickness over the life of the first Grace Mission in Greenland. lost an average of 285 gigatons of ice per year Antarctica lost 137 gigatons per year between 2005 and 2016 sea level rose 3.7 centimeters due to the melting of ice sheets and the expansion of sea water sea level rose continues since 1992 from space. Initially with the Poseidon satellite and more recently with the Json Jason 3 series of satellites used a precision radar altimeter to measure regional and global variation in sea levels in the 20 years to 2014, the average increase was six centimeters , but the increase is not uniform, the red areas show the greatest, white represents no change and blue means a decrease.

The irregularity 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 of these factors must be taken into account to arrive at a baseline against which to measure changes, these blue areas in the Atlantic show a change in the Gulf Stream. The Kamag region in southern France is a low-lying area in the Rhône River delta. In the 1980s a dam was built to prevent the invasion of the Mediterranean. In the last 30 years the coastline here has receded several hundred meters. Scientists are convinced that global warming is responsible and that our alliance to burn fossil fuels has led to excess carbon dioxide in the atmosphere, which traps 93 percent of heat.

Of this heat has been absorbed by the oceans, data from ocean boys' Argo network shows an average warming of 0.9 degrees Celsius since the 1950s, although this may not seem like meteorologists have much understanding of how ocean temperatures sea ​​surface drives hurricanes and cyclones and early predictions of larger magnitude storms are being made. Long-standing climate records are being broken and broken again in 2017. NASA NOAA and the UK Met Office agreed that 2016 had been the hottest year on record globally. There have been 16 of the 17 warmest years. since 2000. Both NASA and Esa have been monitoring the distribution and concentrations of CO2 in the atmosphere since 1992.

This visualization of data collected in 2006 shows the annual fluctuations of carbon dioxide and carbon monoxide. While most of the 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 the increase in atmospheric CO2 levels that are currently occurring. 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 is committed to making information on climate change freely available to policymakers, businesses and research institutions.

Joseph Ashbacher is the director of ISA's Earth observation programs. What you see here in this graph are the CO2 concentrations of the atmosphere over the last 800,000 years and you see these values ​​go up and down in different phases. The blue lines here indicate ice ages and the orange lines here indicate periods between ice ages or periods when it is much warmer. but it is also seen that during the last 800,000 years the value was always below 300 parts per million and suddenly since the last century it rises very sharply to 400 parts per million or even beyond what the delegates distinguished at the recent COP 25 Climate Summit held in Madrid.

It made little progress toward an international agreement to reduce greenhouse gas emissions, while some companies and economies will have to adjust, that task only becomes more difficult as time goes on and much larger adjustments will be imposed on all. Earth is the only place we know that harbors life, but the stability that has enabled this web of life. Plants and animals are fragile and interact for mutual benefit. Our benign environment is the result of the complex and varied creatures with which we share the planet. It is important that we take care of our home.