Foreign Planets: A Tale of Fate and Mystery
In our vast universe, the fate of planets is closely intertwined with the stars they orbit. This is especially true for our own solar system, where the sun dictates the destiny of its neighboring planets. Over time, the changing conditions of our sun have had a significant impact on the potential for life on these planets.
Out of all the planets in our solar system, Earth stands out as a unique and special place. It is the only planet that has managed to retain its water and habitability throughout its history. The stability of Earth's conditions, particularly its oceanic environment, has allowed for the rich biological evolution that has resulted in the presence of life.
For life to exist on a planet, it is not enough for liquid water to simply appear. It must also remain on the planet's surface. Earth's size and geology have played a crucial role in maintaining a stable atmosphere, protecting the precious water that has enabled complex life to thrive. In fact, life itself plays a role in maintaining the very atmosphere that safeguards our fragile ecosystems.
However, as the sun continues to grow hotter, Earth's temperatures rise, leading to disruptions in weather patterns, extreme storms, and devastating droughts. Oxygen levels plummet as plant life declines, eventually leading to the end of complex life on Earth in about a billion years. At this point, Earth will resemble Venus and Mars, with a mostly carbon dioxide atmosphere, turning into a hot oven-like planet. Eventually, as the sun exhausts its hydrogen fuel and enters a red giant phase, it will expand, engulfing the Earth entirely and causing the loss of our planet's atmosphere.
Uranus: A Bizarre and Mysterious Ice Giant
Uranus, one of the gas giants in our solar system, presents a unique and puzzling picture. Its rings, moons, and orientation make it unlike any other planet. Temperatures on Uranus are the coldest of any world in our solar system, and there is not enough heat to drive the storms seen on Jupiter and Saturn. Uranus is an ice giant, and its rings orbit up and over the top of the planet, giving it a bizarre appearance.
The unusual orientation of Uranus hints at an extraordinary past. While most planets in our solar system orbit the sun and spin on their axes in a counterclockwise direction, Uranus spins on its side. Scientists believe that this could be the result of a massive collision with a roughly Earth-sized object during Uranus' formation, causing it to tilt on its side.
The Mysteries of Saturn's Weather and Heat Source
Saturn, another gas giant, presents a different set of challenges when it comes to understanding its weather patterns and heat source. Unlike Earth, where the sun is the primary driver of weather, Saturn receives sunlight that is 100 times weaker due to its distance from the sun. Therefore, some other heat source must be responsible for Saturn's incredible weather phenomena.
Scientists have discovered that the atmospheric systems on Saturn are powered by an internal heat source rather than sunlight. Deep inside the planet, extreme pressure and immense clouds of water give rise to lightning and massive storms. The pressure is so intense that the atmosphere behaves like a liquid metal, able to conduct electricity. This heat source drives Saturn's weather patterns and creates supersonic winds that outpace those seen on Jupiter or Saturn.
Mars: A World of Ancient Seas and Potential for Life
Mars, often called the Red Planet, has long fascinated scientists as a potential place where life could have existed. NASA's Mars Reconnaissance Orbiter has provided invaluable data about Mars, revealing its weather patterns, surface features, and potential habitats for life.
The orbiter has discovered evidence of ancient seas on Mars, such as the Eridania Basin, which held more water than the Great Lakes on Earth. This basin also contains deposits formed in deep-sea hydrothermal environments, similar to those that could have supported life on Earth. These conditions, coupled with Mars' similarities to Earth in terms of initial conditions and history, make it a promising candidate for the existence of life.
Neptune: A Giant Storm and Diamond Rain
Neptune, an ice giant located farthest from the sun, is chemically similar to Uranus but exhibits distinct characteristics. Voyager missions have revealed swirling clouds and incredibly fast winds on Neptune, reaching speeds of up to 1,500 miles per hour. One of the most fascinating discoveries on Neptune is an immense dark vortex within its atmosphere, resembling a giant storm.
Neptune's heat source is another mystery. Some scientists speculate that the buildup of pressure beneath its thick cloud layers turns carbon in methane into rain made of diamonds. As these diamonds melt and fall into the planet's interior, they release extra heat that churns the atmosphere and creates supersonic winds.
Mercury: A Planet of Surprises
Mercury, the closest planet to the sun, has been relatively unexplored due to the challenges of reaching and orbiting a planet in such proximity to the sun. However, NASA's MESSENGER mission provided valuable insights into Mercury's composition and formation.
One of the most intriguing mysteries about Mercury is its disproportionately large core and lack of surface metal. MESSENGER's chemical data revealed the presence of volatile elements on Mercury's surface, which contradicted previous theories about its formation. It is now believed that Mercury may have formed much farther from the sun and migrated closer over time.
Conclusion
Foreign planets within our solar system continue to fascinate and surprise us with their unique features and mysteries. From Earth's stability and ability to sustain life, to the bizarre orientations of Uranus and Neptune, and the potential for ancient seas and life on Mars, each planet offers its own story and challenges for scientific exploration. As we continue to study and observe these planets, we hope to uncover more secrets about the origins and evolution of our solar system.
Foreign music mercury brushes against another planetary embryo this glancing blow removing much of its crust and mental now little more than a metallic planetary core mercury continues toward the sun ending up in the peculiar elliptical orbit we see today before we sent the messenger mission to mercury i think we had a very simplistic idea of what it was going to be like and mercury turns out to be a more complex place with a more interesting and complex history than we had previously imagined but of course all things have to come to an end and once we were out of fuel we could no longer burn our engines to keep from crashing into mercury and sequencers after four years of observations messengers fuel finally runs out and the spacecraft adds yet another crater to this tiny world where any prospects for life were scorched away when it was thrown too close to the sun thank you
The sun's outer corona burns at a scorching one million degrees releasing a barrage of charged particles that traveled at around 400 kilometers per second solar wind
This onslaught would strip away our atmosphere but for the powerful force that protects us the earth's magnetic field solarwind is this stream of charged particles that come streaming out from the sun and at earth which has a powerful magnetic field when those charged particles begin to get close to earth they get diverted around earth by interactions with that magnetic field that protection keeps solar wind and other ionizing radiation off of the surface so on earth where we have this really great magnetic field we are nice safe and sound inside the shell of that protected from all that radiation the magnetic field of earth effectively forms a protective bubble around the earth's atmosphere and when the sun dips below the horizon there are times when earth's protective force field is visible
The aurora is a stunning display of earth's magnetic field in action
It's best seen at the poles but across earth it's protecting our atmosphere and all life on our planet it's vital protective shield is generated deep within the way a magnetic field is generated inside a planet is when you have convective motion in a fluid that is capable of conducting electricity and in the earth that electrically conducting fluid is liquid iron and the molten portion of the earth's core is a place where these motions take place and it can set up a magnetic field
Just like earth mars once had a molten metallic core generating a magnetic field around the planet
Auroras danced above mars's poles protecting its atmosphere and seas below but the field didn't last
In the oldest rocks on mars you see evidence of a once powerful magnetic field you get to the younger rocks the rocks that are three billion 2 billion one billion years old no evidence of a magnetic field whatsoever and there is no intrinsic magnetic field on mars today half a billion years after it formed mars's magnetic field dies out the bright auroras above its poles slowly fade away as the shield that protects the planet shuts down for good once it's stopped stop then what happens is all the atmospheric components things like hydrogen and oxygen that make up water they get stripped away because you don't have the shield the magnetic shield anymore so the high energy particles that come in from the sun and from outer space they begin to strip away the components that make up water without its magnetic field to protect it mars's atmosphere and then water slip away into space so why did mars lose its protective shield what happened deep beneath its surface that stopped mars from developing like earth the answer lies at the beginning of mars's story at its very creation 4. 6 billion years ago when the planets were forming from the dust clouds circling the sun early differences between mars and earth set the young planets on very different paths
Mars forms further from the sun where crucially there is less rocky material to build a planet mars is different because it's not just further out it's actually much smaller if a planet gets to be too small it just freezes all the way through mars is just half the diameter of earth meaning its core cooled more quickly and so it lost the heat that powered the dynamo that generated its protective shield mars's small size condemning the planet to die millions of years ago saturn has an extra moon perhaps 400 kilometers across and formed almost entirely of ice but this moon is doomed it's orbiting just too close to resist the immense forces of saturn's gravity
The rings probably formed from an object that got too close to saturn this is invisible boundary around saturn called the roche limit and that's the limit depending on what you're made of where saturn's gravity is strong enough will actually pull you apart that the gravity on the side closer to saturn is strong enough that compared to the gravity on the other side that will literally rip you apart you don't have enough gravity of your own to stay together a leading theory suggests that just beyond saturn's atmosphere an ice moon approaches close to or even just inside its roche limit as saturn's immense gravitational force pulls it apart the moon begins to rupture catastrophically a world ripped apart by its proximity to enjoy it foreign trillion tons of ice breaks apart in orbit around saturn and thanks to the speeds this material is traveling it's likely that in just a few days it spreads out to encircle the great giant
Saturn's iconic ring is now in place
But as cassini turns its instruments towards it it sees a single ring transformed the images we returned they were phenomenal they were resolution factor of maybe 20 times better than anything we had had before
Cassini reveals how saturn's giant rings have evolved this debris now forms a disc wider than jupiter yet on average just 10 meters thick within moonsized chunks of ice orbit the structure clearing great voids turning one ring into many
But it's as cassini captures images with the sun directly above the equator that the most surprising feature of the rings emerges we knew this was going to be a time for us to investigate the third dimension something that you don't get to see when you just look at picture of saturn's rings and what we found was staggering foreign just right out of the gate we saw vertical structures i just can't tell you how surprised we were to see this it's just the spectacle of it was just unanticipated
I have just imagined flying along in a shuttle craft across the ring right close to the ring so to my perspective it would be almost like it was an infinite sheet of gleaming debris and i'm flying along and flying along and flying along and suddenly i come upon a wall of rubble and that's two miles high
I mean is that cool or what really i've said over and over again they should put that in a movie this once tiny world of rock and ice that has seen the most dramatic transformations is today the solar system's greatest jewel
For more than a decade in orbit cassini has forever deepened our understanding of saturn but its mission is far from over as the young jupiter circles the sun it clears a path through the gas cloud that envelops the early solar system but that process causes it to do something alarming begins to spiral inwards plowing straight through the region of space that would become the asteroid belt when the young jupiter moves through the primordial asteroid belt things get scattered around things get gravitationally deflected and as a consequence of all of this gravitational interaction more than 99 of the original mass that was there is basically now gone by the movement of the giant planets and this has acted to throw material from the asteroid belt out of the asteroid belt into the outer solar system these protoplanetary cores like ceres were never able to graduate to fullfledged planets because there was just not enough material in the orbital neighborhood
When jupiter passed through the primordial asteroid belt its starved series of material halting its growth and the dwarf planet was condemned to live out its life as a cold barren rock but series isn't the only world in our solar system whose development was cut short mars would suffer a similar fate at the hands of jupiter after marauding through what would become the asteroid belt jupiter enters the region of space where mars is forming continuing its journey spiraling towards the sun as jupiter bulldozes inwards its immense gravity scatters material in all directions some is sent careering into the sun and some is thrown out into interstellar space it is because of the gravitational clearing of this neighborhood by jupiter that mars was unable to grow to more than 10 percent of that of the earth this is why mars is small and by clearing material out of the inner solar system the giant planet may also have prevented the formation of the super earths we see in other systems and if it had continued moving inward our planet too might never have formed but then just as it looks like jupiter will sweep everything away the giant planet stops in its tracks because in the shadows of the outer solar system another planet is forming the solar system's second gas giant saturn and its arrival changes everything as jupiter moved inwards saturn moved inwards and caught up to jupiter's orbit when this happened the two locked into a special configuration known as immunotion resonance this is where the planets begin to interact gravitationally in a very coherent manner and now locked as a unit the two reversed their migration course and moved back out saturn caused jupiter to retreat
Leaving behind just enough material from which the inner planets could form mercury venus and our home
Earth isn't exactly the right location to provide the environment for life to develop so if jupiter had moved around even more who knows maybe life never would have developed in the solar system as we know it and as its voyage across the solar system draws to a close jupiter helps to provide our living world with its most precious ingredient
Today twothirds of our planet's surface is covered by ocean more than 1. 3 billion cubic kilometers of water
