Astrum Space - What They Didn't Teach You in School About the Gas Giant Planets

Episode Date: January 6, 2026

A compilation of videos of everything you might not know about our solar system's Gas Giants. From the bizarre characteristics of Uranus, to everything we know so far about Jupiter and Neptune. Take a look at some of Cassini's breathtaking final images. ▀▀▀▀▀▀Astrum's newsletter has launched! Want to know what's happening in space? Sign up here: ⁠https://astrumspace.kit.com⁠A huge thanks to our Patreons who help make these videos possible. Sign-up here: ⁠https://bit.ly/4aiJZNF

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at Yamava.com must be 21-20. Please gamble responsibly. Monopoly is a trademark of Hasbro. Hasbro is not a sponsor of this promotion. When it comes to Saturn, it's hard to summarize just how lucky we were to have the Cassini-Huygens mission. Four robotic probes have visited Saturn,

but of those, Cassini-Huygens has hands down been the most impactful, and I mean that both literally and scientifically. Its data has provided the bedrock for over 4,000 research papers. It discovered six new moons and helped us better understand their composition. It survived 20 years, travelling 7 billion kilometres, and spent 13 of those years around Saturn itself, gathering data on Saturn's gravity, magnetosphere, its rings, and the Earth. and its structure. And Cassini kept gathering data right up until the last moments of its life,

as it plunged into the muster clouds of Saturn's atmosphere and ultimately broke into thousands of pieces. Couple that with the fact that it provided some of the most jaw-dropping, awe-inspiring images of Saturn and the solar system to date, and you have one hell of a mission. I'm Alex McCulligan and you're watching Astrum. Join with me today for this Cassini Supercut as we explore its grand finale, the period of time before the dive, what it discovered before and during its plunge, and the incredible discoveries continuing to be made to this day from the clues that Cassini Hoygens provided us. If you want to see Saturn's beauty, there is no better way to do it than through the eyes

of Cassini in its grand. finale. The first probe to reach Saturn was the Pioneer 11 probe in 1979. It was at this time that scientists confirmed that Saturn's largest moon, Titan, had an atmosphere. They knew they had to go back and visit the moon, but this time with a lander. Now Voyager 1 and 2 were already en route to Saturn at that point, so naturally it was too late to include a lander with those missions. Thus, Cassini Hoygens was born, and in October 1997, it was launched into space.

Getting a spacecraft to Saturn is no mean feat, as the whole trip was combating the gravity of the Sun trying to pull Cassini back to the inner solar system. So to help achieve the speed needed to reach Saturn, Cassini used planets as gravitational assists. It flew by Venus twice, before returning back to Earth. gravity then slingshotted it towards Jupiter, which gave it the final push needed to reach Saturn. This alignment of planets, which allowed these gravity assists, only occurs once every 600 years,

so timing in this case was crucial. And Cassini really scraped past Earth on the second time around too. It was only 1,100 kilometers above Earth's surface at its closest approach. This is made even more interesting when you realize what actually powered Cassini. It was by 3 RTGs, or radioisotope thermoelectric generators. Basically, the power source came from about 33 kilograms of radioactive plutonium. It's this radioactive decay which gave Cassini power, and even until the end of its life, it still produced about 700 watts.

The issue with the spacecraft carrying this radioactive substance was that if scientists had gotten their calculations wrong and a crash landed on Earth, everybody on the planet would have been exposed to the radiation. Now, 33 kilograms spread out over the whole Earth is a very small amount, but in the worst case scenario, NASA estimated it would have caused about 5,000 deaths from cancer. They put this down as an acceptable risk though, as the chances of this happening were only one in a million. Kisini used RTGs because solar panel technology wasn't good enough at the time for the sun

to power something so distant. With RTGs, Kisini would have a very long operational life, and it might still be able to carry on even now if it wasn't for the fact it eventually ran out of propellant fuel. Kisini had numerous objectives. To understand the structure and dynamic behavior of Saturn's rings, explore Saturn's moons more fully, measure the magnetosphere of Saturn, study Saturn's atmosphere, and study Titan more extensively. This last part is where the Hoygens part of Cassini Hoygens comes into play.

You see, Hoygens was a lander attached to the Cassini spacecraft, designed to see what was going on under the hazy clouds of Titan. Ouygens is the part of the mission built and operated by ESA, the European Space Agency. The probe was only about 1.3 meters wide and weighed 300 kilograms. When it detached from the orbiter, it spent 22 days in space before entering Titan's atmosphere. The only system aboard that was active at this point was a wake-up timer, due to wake up the probe only 15 minutes before it entered the atmosphere. And when it woke up, what it saw was amazing.

This video is an actual spared up version of the two and a half hour descent. The main mission of Huygens was actually about this descent, taking readings from the atmospheric pressure, its composition, wind speed and so on. And because the mission was only to measure atmospheric readings, the battery life wasn't expected to last long beyond the landing. The scientists thought they could be landing on an ocean or lake, and so had designed Hewgens accordingly. From what you see though, it actually landed on what could be the bed of a dried up lake.

The mission for Cassini itself has been remarkably successful. As well as scientific data it has picked up over the course of those last 13 years, it has been able to provide some of the most stunning pictures found of space. I just want to showcase some of my favorites of Saturn. And of course, Saturn's moons are beautiful in their own right too. And some very dedicated souls have even taken 1 million photos Cassini has taken to show us what it would be like to be sitting on the Cassini spacecraft. These are real images.

They've only been color corrected and enhanced and put in order to show movement. There's no CGI. It's simply amazing. As Cassini's fuel began to run low, scientists began to consider how best to get the most data they could out of the time they had left. To achieve this, they sent commands to Cassini, telling it to perform some very close flybys of the planet and some of its moons, getting closer to Saturn and its rings than it ever had before. Beginning on November 30, 2016, Cassini repeatedly climbed high above Saturn's North Pole, then plunged

to a point just outside the narrow F-ring, which is the edge of the main rings, completing 20 orbits in total. Then on the 22nd of April 2017, Cassini would leap over the rings to begin its final series of daring dives between the planet and the inner edge of the rings. This was the Cassini grand finale, a series of loops and dives that brought the probe closer and closer to its object of study, facing greater and greater. greater danger as it flew until finally, as its data became purest, as Cassini would fly into the embrace of Saturn itself, Cassini's chance for annihilation would become certain. NASA's website

states the reason for this final mission. As it plunges past Saturn during the grand finale, Cassini will collect some incredibly rich and valuable information that the mission's original planners might never have imagined. The spacecraft will make detailed maps of Saturn's gravity and magnetic fields, revealing how the planet is arranged on the inside, and possibly helping to solve the irksome mystery of how fast the interior is rotating. It will vastly improve our knowledge of how much material is in the rings, bringing us closer to understanding their origins.

Cassini's particle detectors will sample icy ring particles being funneled into the atmosphere by Saturn's magnetic field, and its cameras will take amazing, ultra-close images of Saturn's rings and clouds. No other mission has explored this unique region so close to the planet. What we will learn from these activities will help improve our understanding of how giant planets and families of planets everywhere form and evolve. At the end of its final orbit, as it would fall into Saturn's atmosphere, Cassini would complete its 20-year mission by ensuring the biologically interesting worlds Enceladus and Titan would never be contaminated by hardy microbes that may have stowed away and survived the journey

intact. It's inspiring, adventurous and romantic, and a fitting end to this thrilling story of discovery. But let's take a closer look at some of these final moments. During Cassini's grand finale, NASA became willing to trade Cassini's prospects. for longevity, for a chance at unprecedented levels of closeness to Saturn. This was an easy trade to make. After all, Cassini was running out of fuel, so its survival was already off the table. Making this decision meant Cassini was given the go-ahead to approach the planet closer than ever before, darting in between the rings.

But what did it see? Did this unique perspective show anything we've never seen before? Let's take a look at some of the awesome sights Cassini saw during its grand finale. Well, starting with the moons of Saturn, it has seen some of the shepherd moons in unprecedented detail. This is a close approach of Atlas, a 40km wide moon near the outskirts of the A-ring. What looks remarkable about this moon is the lack of impact craters on its apparently smooth surface, making it look absolutely bizarre. Dust from the rings is collecting over the surface, particularly around the equator of the moon, smoothing it over and giving it this disc shape.

A similar thing happens with the second innermost moon of Saturn, Pan. At 30 kilometres wide and found in the Enka gap, any particles from the rings that stray into the 350 the kilometer-wide path gets swept up by Pan. This keeps the ENCA gap steady and constant. Daphnis is another shepherd moon, sadly not seen in quite so much detail. But due to the gap it is located in, its effects can be seen for hundreds of kilometers. It is only 8 km in diameter and is found in a very narrow gap in the A-ring called the keeler gap.

Its gravity is very weak, but it is just enough to whisk this. nearby dust particles as it brushes by. This creates these waves, or a ripple effect in the nearby rings, sometimes even ripping material directly out of the ring, visible in this little trail here. Not only do these ripples move side to side, but up and down too, as can be seen by the shadows they create. I can only imagine what it would be like to sit on Daphnis and watch as waves follow its orbital path, with glorious Saturn and his many moons in the background, it would be quite the sight to behold.

Talking of the rings though, Cassini has been able to capture some spectacular images. One of my favorites from the grand finale is this one, showcasing the Janus 2-1 spiral density wave. Amazingly, what you're looking at here is the result of the same process that creates spiral galaxies, just much more tightly wound. What appears to be many separate rings is actually only two spiral arms looping around the planet many times, so every second line you see in the image belongs to the same spiral arm. This image is part of the B-ring, at a position where the ring orbits twice for every one orbit of Saturn's moon, Janus, causing an orbital resonance. This photo gives the illusion that the image is tilted away at the top left, but this isn't the case.

The illusion is created by the way density waves propagate from the planet, the wavelength decreasing with the distance from the resonance, and this is where the resonance gets even more mind-blowing. Janus, the moon that contributes to the resonance, switches positions every four years with its close neighbor moon, Epimetheus. Every time this switch takes place, the rings respond, creating a new crest in the waves. NASA says, the distance between any pair of crests corresponds to four years' worth of the wave propagating downstream from the resonance,

which means the wave seen here encodes many decades' worth of the orbital history of Janus and Epimetheus. According to this interpretation, the part of the wave at the very upper left of this image corresponds to the positions of Janus and Epimetheus around the time of the Voyager flybys in 1980 and 1981, which is the time at which Janus and Epimetheus were first proven to be two distinct objects. This encoding reminds me a bit of a tree trunk encoding how many years it's been alive by the amount of rings it has. Simply amazing. Apart from other beautiful and detailed images of the rings, other interesting sightings have been these little propeller features dotted

around the rings in a number of locations. This image shows both sides of the rings. The top image shows the illuminated side and the bottom the unlit side. Scientists do this to compare and try to figure out details. Even though the scale of the image is only about 500 meters per pixel, the moonlit might not even be able to be resolved. You might just be able to see some trace of it in this top image, But what can be seen is that the moonlet is physically connected to the rings by this band of materials.

As I mentioned, this wasn't the only moonlet trying to create a gap in the rings. Here is another, found right next to the anchor gap, and here is another, and probably the biggest out of all three. None of these moonlets are thought to be bigger than two kilometres, and probably have the density of a snowball. The last interesting thing Cassini was able to image within the rings is extremely small but solid objects which are formed around the F-ring, potentially caused by the perturbations of some of the shepherd moons around there.

They seem to be solid as they have survived crashing into the F-ring a number of times, kicking out dust and particles which sometimes then even follow their orbit, as can be seen by the haze around them. The objects themselves are not actually visible due to the dust obscuring the view. Lastly, let's look at the planet itself. As Saturn's northern hemisphere was in full summer at the time Cassini flew by, its remarkable hexagon around the pole was in full view. In the center of the hexagon is found a permanent polar vortex with the eye wall of a massive

hurricane. Interestingly, the pole seems to be changing color with the season, as you can see quite clearly, in comparison to 2012, where the pole appeared quite dark in colour. With the assistance of other wavelengths of light, other storms are visible and could be seen dotted all over the planet, as well as bands reminiscent of Jupiter, just not quite so vivid in natural light. Also, because of the proximity of Cassini to the planet, it was able to get a good look at the planet's horizon.

On the left of the image can be seen a haze in the stratosphere of the atmosphere that disappears towards the right of the image. When Cassini did enter the atmosphere on its final approach, it was thought it would not survive to even reach this haze. However, scientists weren't too worried about that. What was of particular interest to scientists is what the atmosphere consists of. Cassini would dive into that atmosphere to find that information and would burn up in the process, making it the last readings that Cassini would ever send.

But one week before it entered the atmosphere, Cassini was still taking images. Some of these final images are fantastic, although be aware that Cassini is not capable of real-time video capture. The videos I'm about to show you are time lapses, the splicing together of countless individual images into glorious visualizations of what it would be like to fly with Cassini on its ultimate journey into Saturn. Not all of these images are of Saturn itself. The first time lapse we will look at is from the 8th of September 2017, only one week before

the end of Cassini's mission. One of the main focuses of Cassini during its mission was the Moon Enceladus, one of the prime candidates in the solar system to contain life in a subsurface ocean. discovered over 100 water plumes erupting through the moon's crust from this ocean, water which freezes in the space environment and has now formed the beautiful E-ring around Saturn. This ring is very tenuous, only visible when backlit by the sun, and is potentially the bluest naturally occurring object in the solar system. Here is a great view of Enceladus's effect on the densest part of the E-ring.

You can see the plumes disturbing and replenishing the ring. Cassini's final look at Enceladus' plumes were captured in this remarkable time lapse taken over a 14-hour period. You can't reason with the sun. Trust us. We've tried. This summer, it's time to put that angry ball of fire on mute. Columbia's Omnishade technology is engineered to protect you from the sun's harsh rays

that can burn and damage your skin. The sun is relentless, but so is our gear. up your summer at Columbia.com to spend more time outside and less time slathering on allotion. You're welcome, Columbia, engineered for whatever. On the 11th of September, Cassini was near the furthest point of its final orbit and captured this beautiful mosaic in natural light. Visible are the thickest of Saturn's rings, D, C, B, A, and F, with Saturn's short shadow being cast over them.

Saturn's northern hemisphere was experiencing summer during this time, which means that Saturn's most famous hexagon storm is visible in all its glory. You can also just about notice Saturn's subtle bands in natural light. What's really interesting about this image, however, is that the night side of Saturn is dimly illuminated. This is due to light reflecting off the rings, meaning Saturn's nights in the hemisphere facing the sun don't get that dark. Below the glow of the rings, Saturn is pitch black.

As Cassini began to approach Saturn again on the 12th of September, it took images of Saturn's atmosphere near the planet's Terminator line. Incredibly, because the sun is so low in the sky here, huge cloud structures can be seen casting shadows that stretch for many kilometres. You may think this is a close-up of Saturn, but actually we are looking at the scene about 5,500 kilometres across. Saturn's moon Titan could easily fit in this shot. Cassini was getting closer and closer to Saturn.

On the 13th of September, it peered one last time at Daphnis. And some of you keen observers will notice ripples in front of the moon as well as behind. This is due to orbital speeds of the rings and the moon. The inner ring orbits faster than Daphnis, meaning the ripples overtake the moon, exposing more ring material to the moon's gravity. On the other hand, the outer ring travels slower than Daphnis, meaning the ripples lag behind the moon. By the time the ring material reaches Daphnis on either side again, the ripples have already smoothed out.

On the same day, Cassini had one last look around the Saturn system. It captured a view of Titan, a moon it focused on heavily during its mission, a remarkable world with a thick nitrogen atmosphere. It also appeared at Saturn's rings, with the uneven F-ring just about visible at the bottom of the image. And as Saturn got bigger, it took one last look at Enceladus over a 40-minute period before it disappeared from view behind the limb of Saturn. The final image Cassini ever took was looking over the region where it would plunge into

the atmosphere. It was night time here, and so Saturn is lit up by light reflected off the rings. On the final day, photos were not on the science agenda. As beautiful as they are, they use up a lot of valuable bandwidth, and scientists wanted to get every bit of data real time before the spacecraft was destroyed. This was a unique opportunity. We had never probed Saturn before this. When Cassini first hit the tenuous parts of Saturn's atmosphere, it was traveling 123,000

kilometers per hour. The remnants of Cassini's fuel were deployed by its thrusters to keep Cassini's antenna aimed at Earth. At this point, Cassini was 1,900 kilometers above Saturn's clouds. A minute later, these thrusters were firing at maximum capacity to keep Cassini from spinning out of control. Cassini was directly sampling Saturn's atmosphere, but this atmosphere was also heating Cassini up.

10 seconds later, the thrusters were overcome, and Kisini began to tumble, cutting off communication with Earth. Kisini's onboard computers at this point would have been trying to figure out what was going wrong. Gyroscopes and star trackers would tell the computer that it is spinning, and it would likely have gone into a safe mode to divert power in an attempt to write itself. A minute or so later, the spacecraft would have disintegrated altogether and burned up in Saturn's atmosphere.

As data started arriving one and a half hours later on Earth, this final part of the mission was deemed to be a great success. Kassini recorded data from direct analysis of Saturn's atmosphere, its ionosphere, dust particles in the atmosphere, and from magnetic field measurements, and perhaps more that has yet to be uncovered from the data. And that's the amazing thing about the Cassini mission. It just keeps on giving. Science papers and discoveries are still being made as the data it collects.

is analyzed and re-examined. What have we discovered from Cassini's data in the years since its groundbreaking mission? You're about to find out. But be aware, some of the things Cassini has learned about Saturn has only served to make the planet even stranger. You may think you know Saturn. Its iconic rings are the largest in the solar system, and its hazy, yellow surface is both enigmatic and instantly recognized. It is the second largest planet, the least dense, and the six from the sun. And yet, Saturn is an enigma. There is a vast mystery lurking beneath its obscuring atmosphere, uncovered by the Cassini

probe, one that the scientific community still does not have consensus about. Saturn behaves in ways that our conventional models claim is impossible. its temperature, to its magnetosphere, to even the very length of its days. What is going on with Saturn, and what are our best attempts at explaining these baffling phenomena? The Cassini probe arrived at the gas giant on the 1st of July 2004. It was not the first probe to arrive at Saturn, three others had already done flybys. However, it was the most thorough. As we have already mentioned, it spent 13 years circling the planet, collecting reams of

data using its various spectrometers, magnetometers, and other equipment. The knowledge it gave us has been a huge benefit, but sometimes only serves to deepen Saturn's mysteries. Take for example that hexagon storm on Saturn's North Pole. The edges of this 29,000-kilometer-wide storm could each fit the Earth comfortably inside, and as best as we are able to tell, does not shift its longitude, remaining fixed at its location, travelling with the rotation of the planet, unlike the rest of Saturn's swirling clouds, pushed along by its up to 1,800 km per hour winds.

The storm is undeniably a strange one. Scientists do not yet have a full explanation for it, Although there are some lab experiments that have created close approximations to hexagons on much smaller scales, but it is not alone. As the mountains of Cassini data started getting analyzed in the years since the end of its mission, more mysteries have started coming in. It started with a fairly innocuous question. How long is a day on Saturn? Although we've watched Saturn in our sky for thousands of years, scientists did not yet

have a definitive answer. After all, it wasn't as simple as looking up at the planet and seeing how long it took for its rocky core to rotate. Saturn's thick cloud cover obscures any landmarks that might exist on any hard surface below, and those clouds move at different speeds to the core due to the powerful wind. The rings themselves orbit Saturn at different speeds, so they don't settle this question. You can't look at how fast they orbit and hope it's the same. After all, most moons don't do this, so rings are no different.

Rather cleverly, scientists do have techniques for figuring out the rotation of a gas giant by looking at its magnetic field, and it was hoped that this method might be used on Saturn. With magnetic fields produce them via a dynamo effect. As the planet rotates, liquid metal in the core spins and shifts, and this colossal motion of molecules creates massive currents of energy, which in turn produce magnetic fields. One feature of this is that, thanks to this rotation, the pole of this magnetic field is always off from the axis of rotation for the planet itself. If the two lined up, the magnetic field wouldn't survive for long.

So all you have to do is detect the magnetic fields around a planet, which Cassini could do, and watch as the magnetic pole shifts in a circle around the true axis of the planet. Once the magnetic pole has completed one rotation, you have your day. Only Saturn apparently does not play by the rules, and its magnetic pole is almost perfectly aligned with its axis of rotation. to an order of accuracy of less than 0.1 degree. And, in spite of Dynamo theory claiming that this should be impossible, Saturn's magnetic field is alive and well.

Its magnetic moment is 580 times more powerful than Earth's, and is extremely influential on the Saturn system as a whole. Scientists do not know how this magnetic field occurs, as it is impossible under Dynamo theory, no other method for producing such a field is proven. Either a planetary dynamo is at play in Saturn's core, but some other effect is occurring in the atmosphere to warp the magnetic field lines to be perfectly aligned with the axis of rotation, or we are observing a completely new method of producing a magnetic field on Saturn. So it was back to the drawing board for solving a Saturn day. Fortunately, But, radiation proved to be of more help.

Saturn is an electrically live system. Charged ions move between the layers in its atmosphere, even between its rings and its ionosphere. Scientists noticed that Saturn emitted radio waves as a result of all the magnetic fields at play, and these radio waves rose and fell in intensity. In fact, it seemed to mirror what you might expect to see as a result of the planet rotating. Their levels of radiation would appear every 11 hours or so. As a result, scientists concluded with some certainty that this was Saturn's day length. Their initial estimate based on Voyager data was 10 hours 39 minutes and 23 seconds.

It was hoped that Cassini would be able to improve the accuracy of this figure. Initially, Cassini was able to do so. But then it got really weird, because over the course of the 13 years, the years of the 13 years years of Cassini's study of Saturn, this number started to shift. It drifted about 1% over the course of a year, sometimes rising, sometimes falling. This almost seemed to imply that the planet itself was altering the speed of its rotation, sometimes speeding up and sometimes slowing down. To be clear, a planet as massive as Saturn should not be doing that.

As such, scientists concluded that this wasn't happening. and some effect must be once again muddying the waters around Saturn. Some aspect of the atmosphere was causing shifts in the fields, making the radiation fluctuate over time, hiding the true rotation of the planet beneath a cloaking shimmer. Another key consequence of the planet's magnetic field is the auroras that shine at Saturn's poles. But while on Earth, our auroras are the result of solar wind interacting with our atmosphere, is thought that this does not account for the auroras on Saturn.

Kisini detected that at least some of them occurred regardless of what the solar wind was doing at the time, meaning that Saturn's auroras are non-solar originating. Something strange must be going on inside Saturn. It was hotter than it ought to be too. It radiates out into space about twice as much as it receives from the sun, and while some Some of this may just be gravitational compression of the planet, the rest needed some other way to account for it. Ultimately, all of this needed some unifying explanation.

And fascinatingly, thanks to Cassini's data, we discovered the key to all of it may lie within Saturn's gaseous atmosphere. Saturn is a gas giant. It is almost entirely made of hydrogen and helium. Not all of this is gas, as the great mass of Saturn means that the deeper into its atmosphere you go, the more intense the heat and pressure that you are subjected to. It is thought that this pressure forces gaseous hydrogen to become liquid metal. Some scientists theorized that this liquid hydrogen, or perhaps even hydrogen compressed so

densely that it becomes diamond, rains down into the depths of Saturn, and the friction this generates, explains some of Saturn's unusual heat. But the rest comes from the auroras. Although these are not fully understood, it is thought that they are the product of electrically charged particles coming into Saturn from its rings and moons. Whatever their source, these auroras may be creating enough heat to warm the upper atmosphere of the planet. Temperatures so hot create other effects.

Where warm fronts meet cold, powerful winds are formed. It is theorized that these winds carry charged ions around Saturn's upper atmosphere, and these electrically charged winds are what is skewing the data from Saturn's radiation, causing its variance. Perhaps such motion of electrical currents might also explain why Saturn's magnetic fields are not where they are supposed to be. This could be caused by a conductive layer within Saturn's clouds, moving at a different speed to the others, creating fields of their own. At least, so goes the explanation.

In all this, it should be clear that many of these answers lack final proof. Scientists are trawling through the data given by Cassini, hoping for further insights. If these are not forthcoming, then ultimately it will take another mission to Saturn to find the answers to these puzzling questions. But what about the length of Saturn's day? Thankfully, this one mystery does have an answer, and it turned out the clue lay in the rings after all. Rather than investigate the electrical and magnetic effect of Saturn on its rings, scientists realized that Saturn would also target them through its gravity. This is fairly obvious, but what was more insightful was that Saturn would not target them

uniformly. Saturn is not a perfectly round ball. Any variance in its shape, result? involved invariance in its gravitational field. Saturn's rings were a perfect canvas to look out for such variance. As Saturn pulled at its rings with a rising and falling force at certain locations in the rings, it would be able to detect ripples. Scientists started looking for these ripples and located them. By measuring the distance between them, it was finally possible to calculate the length of Saturn's day.

They weren't far off. It was 10 hours, 33 minutes, and 38 seconds. And this time, scientists are fairly certain that they've got it right. So at least this mystery was solved. And yet Saturn's other mysteries still persist. The next mission to Saturn will launch in 2027 with NASA's Dragonfly, although this will focus more on exploring Titan, Saturn's largest moon. is the most earth-like object in the solar system, as it is the only place thought to have

atmosphere filled with nitrogen, similar to ours, albeit with no oxygen, and rain cycles, and liquid lakes on its surface, although these are methane rather than water. So it's understandable why scientists want to give it a look. Still, it means that it may be some time before Saturn's deepest mysteries find themselves answered. Saturn breathes. The winds that might prove to be the lifeblood of the system thrum and flow across its atmosphere. Its delicate balance of magnetic fields and gravity coax at its rings, keeping them perfectly aligned.

Saturn's rings are thought to be surprisingly young. Saturn may be over 4 billion years old, but there is evidence that the rings may have only formed in the last 100 million years, and they are slowly draining back down into Saturn's atmosphere. So in another 100 million years, they may be gone. This is sad to me, but I also feel strangely fortunate. If humanity hadn't arrived when we did, we might have missed this beautiful cosmic sight. It may be unscientific to say that, as the planet has no real choice in whether it gives us a gift or not, but I'm nonetheless grateful to have been witness to the enigmatic and wondrous

world that is Saturn. And seeing those enigmas and wonders, all the beauty, all the scientific data, just would not have been possible if it had not been for the incredible Cassini-Huygens. This truly was one of the greatest space missions of our time. Jupiter. A place of colossal storms, deadly radiation and captivating beauty. A powerhouse whose mass is so great, it influences even the world. the Sun itself. Jupiter is fast becoming one of the most studied objects in our solar system,

with seven flybys, two orbitors, with one still in operation today, and two additional planned missions. There is so much to know about the fifth planet from the Sun. What causes its distinctive red coloration? What is it made of? What lies beneath its obscuring clouds? What do we know about its great red spot. Jupiter holds a vital role in protecting our solar system, and it's time to delve into its mysteries. I'm Alex McCulligan, and welcome to Astrum. Join me today as we explain everything you could want to know about Jupiter. Marvel Television's Wonder Man, an eight-episode series, now streaming on Disney Plus. A superhero remake, not exactly what we'd expect from an Oscar-winning director.

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Only on Disney Plus The Fifth Planet from the Sun Jupiter is found on the outskirts of the asteroid belt And sits between the orbits of Mars and Saturn It is 778 million kilometers away from the Sun on average, or 5.2 astronomical units, and completes an orbit every 12 Earth years. The axle tilt of the planet is small, only 3 degrees.

This means it doesn't experience much change in seasons, unlike Earth and Mars, and very much like Saturn, its radius at the equator is greater than at the poles. It is a massive planet, the largest in our solar system. It is so massive, its mass is a thousandth that of our sun. That might not seem like a lot, but once you realize the sun contains 99.86% of all the mass in the solar system, you'll realize that Jupiter equals almost the remainder. Its mass is two and a half times that of all the other planets in the solar system combined. And this brings about an interesting phenomenon.

The barricentor between Jupiter and the Sun is actually above the surface of the Sun at 1.068 solar radii from the Sun's center. Let's talk about barricenters. When we think of an object orbiting another object, we don't necessarily think that the smaller object has a gravitational influence on the bigger object. That's because most of the time the effect is negligible, like the ISS orbiting Earth, even Mercury orbiting the Sun. But it does still happen.

A barricentor is the center of mass between these two orbiting objects, or the location in space they both orbit around. With Jupiter being the mass and distance from the Sun it is, unlike Mercury, its effect is far from negligible. As Jupiter swings around the Sun, both of them do a little dance around this center of mass, which is actually above the surface of the Sun. Let me show you this principle with an example. If I get a heavy object and a less heavy object and attach them to the ends of a long stick,

in order for the stick to balance, we need to find the center of mass. As you can see, the center of mass is closer to the heavier object. Imagine this is the Sun and Jupiter, with the stick being gravity, and you'll understand how a barricenter works. While Jupiter has the greatest mass of any planet in the solar system, it's not the densest. It is the most massive because it is the largest. If Neptune was the same size as Jupiter, it would be the most massive. And if Jupiter was the same size as Earth, Earth would be over four times more massive.

As it is though, the diameter of Jupiter is 11 times that of Earth, and its total mass is the Total mass is 318 times more than Earth's. As we know, mass affects gravity. This means that Jupiter has a huge gravity, over twice that of Earth at 2.528G at its surface. The gravity of Jupiter is so influential in the solar system that it affects every planet to one degree or another. Its gravity is strong enough to tear asteroids apart and capture 60s 6,000. 7 moons at least.

Some scientists think that Jupiter destroyed many celestial objects in the ancient past, as well as preventing other planets from forming. One example of this, in particular, is 4 Vesta. Scientists even predict the gravity of Jupiter is so significant around the solar system that it is perturbing Mercury's already eccentric orbit enough that in a few billion years, tiny planets may either crash into the Sun or be ejected from the Solar System altogether. At the moment though, it could be the hero of the four inner planets. Without Jupiter acting as a cosmic vacuum cleaner, it wouldn't be sucking up dangerous objects

like long-period comets, or perturbing their orbits enough to give them a little kick of energy so that they leave the solar system altogether. Jupiter is the fifth planet from the Sun, and it's five times further away from the Sun than Earth. Even so, it can be the third brightest object in the night sky after the moon and Venus. I just want to show you how bright that is. Just using a handy cam, we can see Jupiter quite easily in the night sky. With a maximum magnitude of minus 2.94, it can actually cast shadows. As a result of it being so obvious in the sky, it makes It's a very nice target for amateur astronomers.

As consumer telescopes have improved in recent years, it's amazing what details you can see from your back garden. And what makes these famous patterns? The cloud layer is only about 50 kilometers thick and contains ammonia crystals, much like on Saturn, but the coloration comes from compounds heating up from deep within Jupiter and then rising. These compounds are known as chromophores. And when they reach the clouds, they interact with the UV light of the sun to create these

spectacular, multicolored bands. This is quite the cycle, though, and the face of Jupiter can change dramatically over time. Even if their colors do change, the actual latitude of these bands remains consistent enough to be given identifying designations, but they can vary in width over the course of time. of storms and turbulence occur where these bands meet, and it is the reason and engine behind Jupiter's very famous Great Red Spot. This storm is huge. It can easily fit the diameter of Earth within it.

It has existed for as long as we've known, since it was first discovered in the 17th century. It might very well be a permanent feature of the planet, but interestingly, it has decreased in size since observable. the reason for its reddish color is unknown, and the color of the spot can vary greatly, from brick red to almost white. The most recent theory for its color is chemical compounds being broken up by the UV light from the sun, much in the same way as the process that happens on the rest of the planet. The storm is actually much higher up in the atmosphere than the surrounding clouds,

and as a result can interact with the sunlight a lot more. This would explain why its color can be much stronger than anything else around it. But Jupiter doesn't just have one scientifically interesting storm. Another storm, known as Red Spot Jr., formed when three storms merged into one between the years of 1998 and 2000. And it has so far passed unscathed by its bigger neighbor and is now quite a prominent feature of the planet. It could last for another couple of hundred years.

if it avoids the same fate of a similar storm which passed right through the heart of the great red spot. So what do we think Jupiter is made of? Well, much like Saturn, under the atmosphere are gaseous, then liquid and in metallic forms of hydrogen. The further into the planet you go, the greater the pressure becomes. Under immense pressure, hydrogen acts as a metal. And beneath that is an ice or... a rocky core. Because we can't recreate on Earth the immense pressures Jupiter experiences, we don't really

know what properties these materials have at the core. Roughly 90% of Jupiter is thought to be hydrogen, 10% helium, and then trace amounts of methane, ammonia and others. Jupiter rotates very fast, faster than any other planet, completing a rotation in only 10 hours. But due to it not being solid, it doesn't rotate the same speed all over, a rotation at the poles taking five minutes longer than at the equator. As a child, I was very curious why Jupiter wasn't a star. Considering Jupiter is so massive, plus it is predominantly made of flammable hydrogen, surely someone

just needs to throw a match in to set it alight. Well, the sad news for my inner child is that stars don't really work that. way, plus there's barely any oxygen on Jupiter to allow for combustion. Stars produce their heat from nuclear fusion caused by the extreme pressures found at the star's core. Current thinking is that Jupiter would need to be roughly 75 times more massive than it is now to be massive enough to be a star. Although, interestingly, its volume isn't too far off from the smallest known red dwarf.

And yes, you may have noticed in this picture, Jupiter is a large. Jupiter does indeed have rings. Nothing on the scale of Saturn, but there are four planetary rings. The main ring is very thin, but very bright. The rest quite wide, but exceptionally faint. The main ring is about 6,000 kilometers wide, and the only distinctive feature you will see is what is known as the Metis notch. Something else to note about Jupiter is its remarkably strong magnetosphere.

It is 14 times stronger than Earth's due to the planet's liquid metallic hydrogen center. This makes it the strongest magnetosphere of any planet in the solar system, and is only beaten by the sun's sunspots. There are a couple of reasons why this is really interesting. The first is that magnetosphere channels solar wind to the planet's pole, which produces magnificent to Aurora. The second is that the four biggest moons of Jupiter are protected from this solar wind, because they orbit within the magnetosphere.

This implies they don't need their own strong magnetospheres, because Jupiter is doing that for them. However, this doesn't mean they are safe from radiation. Jupiter has a powerful radiation band around it, the same radiation band that has crippled any probe that went through it. The closest large moon to Jupiter, I.O. passes right through the heart of this radiation band, receiving 3,600 RAM per day on the surface. For a point of comparison, anyone exposed to this much radiation would be dead within four hours.

Not the best home away from home, then. When it comes to the Jovian moons, I'll only very quickly talk about them because I have made a separate video about them here. Jupiter has 67 known natural satellites. 51 are under 10 kilometers in diameter, but the largest, the Galilean moons, are some of the biggest in the solar system. They are Io, Europa, Ganymede, and Callisto, and they are all interesting in their own right. Ganymede is actually the biggest moon in the solar system and has a greater diameter than that of Mercury.

And with this final thought, take a look at Jupiter through the infrared. Demonstrating the immense size and power of this planet, this dot at the bottom of the planet is the impact of an object from space, which, if it had hit Earth, could have spelled the end of our planet as we know it. We can be glad Jupiter is there, not only for its beauty, but because in so many ways it is an asset to our solar system. so much for watching this far. Did you learn something today about Jupiter you never knew before? And what planet remaster would you like to see next on this channel for this series?

Let me know in the comments below and I'll see you next time. Uranus, the ice giant. This cold, bluish-gray marble seems like a desolate waste in the far reaches of the solar system. But in actuality, there are some fascinating facts about this planet which make it unlike anything else in the solar system. I'm Alex McColgan and you're watching Astrum. Stick with me on this journey and we will explore almost everything you could want to know about Uranus. The first unique aspect of Uranus is its name.

All the planets are named after Roman gods except Uranus. It's named after the Greek god of the sky, Oranos. The Latinized version of this word is what we use today. Had they just kept the Greek version, it might have saved a bit of embarrassment as people stumble over-saying Uranus in a polite way. It even has two ways to pronounce it, as no one has been able to definitively agree on the matter, Uranus and Uranus. Uranus is also very special in the way it rotates and orbits.

It is the seventh planet from the Sun, the second from last planet. It orbits on average around 19.2 astronomical units from the Sun, which means it is over 19 times further away from the Sun than our Earth. This varies throughout its year by 1.8 astronomical units, the biggest difference of any planet. Being this far away from the Sun means it is freezing cold, minus 220 degrees Celsius cold, which makes it the coldest planet in the solar system. Its year lasts 84 Earth years. When it was first discovered, astronomers attempted to predict its orbit.

After some time though, they realized it hadn't followed their predictions, and concluded that the reason was because there was another planet that had a gravitational influence on it. They mathematically predicted where this planet should be, and as a result, Neptune was discovered. Interestingly, the same theory surrounds this as-yet-undiscovered planet X or planet 9. Some far-out objects in our solar system are not where they should be, and theory suggests This is because of another planet that has a gravitational influence on them. The hunt is now on to actually find this planet. You said this place was steps from the water.

We just haven't found the steps yet. How much did we save? Enough. Enough to get lost. Or you could book a stay with Hilton. Welcome to your ocean front room. Just steps from the water. The Hilton sale is on now.

Book on Hilton.com or the Hilton app and save up to 20% to get the stay you expected. When you want savings, not surprises. It matters where you stay. Hilton, for the stay. When you need to build up your team to handle the growing chaos at work, use Indeed-sponsored jobs. It gives your job post the boost it needs to be seen

and helps reach people with the right skills, certifications, and more. Spend less time searching and more time actually interviewing candidates who check all your boxes. Listeners of this shell will get a $75-sponsored job credit at Indeed.com slash podcast. That's Indeed.com slash podcast. Terms and conditions apply. Need a hiring hero? This is a job for Indeed sponsored jobs. What's really interesting about Uranus is its rotation. Most planets rotate like a spinning top on the table of the solar system plane. Not Uranus. No, Uranus has fallen over and is rolling

instead for large portions of its year. You see, its axle tilt is 97 degrees. This means its seasons are crazy in comparison to the rest of the planets. During its solstice, or the time of year when the sun is highest or lowest in the sky, one hemisphere of the planet always faces the sun, while the other is in complete darkness. It kind of looks like the planet is rolling along its orbit. Only a very narrow strip near the center of the equator of the planet experiences day and night during this time, but the sun does only just rise above the horizon. The poles on the other hand get 42 years of continuous darkness, followed by 42 years

of daylight. During its equinox, which is the opposite of a solstice, the planet has a more normal day-night cycle. Uranus is currently leaving its equinox, having passed it in 2007, and is now heading back towards a solstice. Uranus rotates once every 17 hours and 14 minutes. Because its surface is not solid, however, some parts of the atmosphere rotate faster than others, and due to high winds, some sections can make a full rotation of the planet in only 14 hours.

This strange rotation and axle tilt means it is the only planet in the solar system that gets more energy from the Sun at its poles than at its equator on average. For some reason, though, the equator is hotter than at the poles, and no one really knows why. Speculation also exists as to why Uranus rotates the way it does in the first place, although it is generally accepted with a large Earth-sized planet crashed into Uranus, knocking its rotation on its side. How big actually is Uranus? Well, it is the least massive of the gas giants at 14.5 Earths compared to Neptune's 17 Earth

masses. Its diameter, though, is just bigger than Neptune's at 50,700 kilometers, about four times more than Earth's. Because this mass is spread out over a large area, the gravity on Uranus is only slightly less than on Earth, at 7.8 meters per second squared, or 0.89 . That would feel quite comfortable. And what is it made of? Well, it is believed to have a core just smaller than Earth of.

rocky silicate material, which is surrounded by a mantle of water, ammonia, and methane ices. Although it's referred to as ices, this mantle is in fact very hot, reaching almost 5,000 degrees Celsius, and is more like a liquid ocean surrounding the core. So, to call Uranus a gas giant is a bit disingenuous, it is certainly not gaseous all the way through. The atmosphere is in fact very insubstantial in comparison, only consisting of a total of 0.5 Earth masses, with most of the mass of Uranus being in this core and mantle.

The atmosphere is comprised of mostly helium, hydrogen, and 2.3% methane, and then a cloud layer on top. It's this methane that gives Uranus its aquamarine or cyan color. Interestingly, some models suggest that pressure at the base of the mantle on Uranus is enough to break the methane molecules apart, which then compresses the carbon atoms from the methane into diamonds. These diamonds rain through the mantle like hailstones. The very base of the mantle could be a layer of liquid diamond or carbon, with solid diamond

berks floating in it. We'll fly away from the planet just a little bit now to have a look at its planetary ring system. Uranus, much like the other larger planets in our solar system, has rings. It has 13 very dark and young rings. Most are not bigger than a few kilometres wide, and they are thought to only be 600 million years old, much younger than Uranus. They are comprised of extremely small particles, the biggest being only a few kilometres across, made of water ice and dark radiation processed organics.

Albedo doesn't exceed 2% or in other words, they are darker than wet soil. As we'll see shortly, Uranus has a lot of moons, and the rings are thought to be the result of high-impact collisions with some moons in the past. It is unclear why some of the rings are kept so narrow. The usual explanation being that the rings are kept in line by Shepard moons, but this is only the case for one of the rings here. was discovered to have rings in 1977, when an occultation of a star occurred. The star dimmed a few times on either side of Uranus as Uranus moved in front of it, confirming

the presence of rings. Uranus has only been visited by spacecraft once, and that was in 1986 by Voyager 2. Voyager discovered a lot of the rings and moons of Uranus, giving us close-up shots of the faint ring system. When Voyager flew by, though, this only brought. the total of known rings to 11. When Hubble was launched, it also had a look at Uranus, discovering two additional rings that had never been seen before.

The outermost ring is twice as far away from Uranus as the previously thought outermost ring. And as promised, here is a look at the many moons. Unusually, the moons are named after figures in English literature. Overall, Uranus has 27 known moons divided into three categories. The 13 inner moons, 5 major moons, and 9 irregular moons. The inner moons are connected with the rings of Uranus, some of which may have provided the ring's materials.

The largest of these moons is called Puck, at only 162 kilometers in diameter. It is the only inner moon to be captured in detail by Voyager 2. Interestingly, these inner moons constantly perturb each other, and the system is very unstable. There's a good chance that some of them may collide again in the future. The five biggest moons, in order of distance from Uranus, starting on the left, are Miranda, Arial, Umbriel, Titania, and Oberon. Titania is the largest moon of Uranus and the eighth largest moon in the solar system at 1,600 kilometers.

Again, as can be seen, these are very dark objects, umbriol being the darkest. With the exception of Miranda, which is comprised mainly of water ice, the rest are thought to be a mix of water and rocky materials. These moons may have differentiated interiors, meaning a core of rocky material with a mantle of ice. Between the core and the mantle could well be an ocean layer of liquid water. Interestingly, the axle tilt of the large moons is the same as Uranus, meaning that during solstice, if you were to look at the sun, it would only ever move in a circle in the sky, never setting.

During solstice, only one side of the moon faces the sun, meaning a constant daytime. The final nine known moons are irregular moons. They are likely to be captured objects, and are much further out than the last of the big moon Oberon. They vary in size from 20 kilometers to the biggest, Psycho-Rax, which is about 200 kilometers in diameter. Finally, let's explore Uranus' climate and magnetosphere. Uranus' seasons are quite unique in the solar system due to its exceptional axle tilt. Telescope technology has only allowed us to resolve details on the surface of Uranus for the last few decades, which means it's difficult to be able to say with certainty if there are

changes between Uranian years. What has been observed, though, is that as the planet approaches solstice, the pole brightens and a collar forms. Moving away from solstice, the pole and collar dim. This brightness is thought to be due to the thickening of methane clouds, although the cause is not clear. Seasons also affects storms in the upper atmosphere. Storms are relatively rare on Uranus compared to other gas giants, but are thought to be caused

by changes in the seasons. With the improvements in telescope technology, we've also been able to observe bands stretching around the planet, much like the other gas planets. However, these bands are mainly visible in the infrared, which is why Voyager was only able to show us this invisible light. In these infrared images, you can also see small storms dotted all over. And another unique feature of Uranus is its unusual magnetosphere. Usually magnetospheres originate from the geometric center of the planet, but that's not the case

with Uranus. Also, it's not in line with the rotational axis, but it's 59 degrees off. This unusual placement means the magnetosphere is much stronger at the North Pole than at the south. One theory for this is the liquid diamond ocean could deflect the magnetosphere. or even that it is not the core of the planet that produces the magnetosphere at all, but rather the liquid mantle. The magnetosphere is about as strong as Earth's, and because of its unusual rotation,

the magnetotail corkscrews off for millions of kilometers into space. Look up into a clear night sky with your naked eye, and what planets would you see? Technically, you would be able to see all of them at one time or another, All of them apart from Neptune. It is the smallest of the gas giants and also the furthest away, and it is a perplexing place. You would think a planet so far from the Sun wouldn't have a dynamic atmosphere that exhibits ginormous storms and super-fast winds, and yet it does. So why is this planet as interesting as it is?

I'm Alex McColgan and you're watching Astrum. And today we're going to delve into everything you could want to know about Neptune. Let's start right at the beginning. Neptune is the only planet found through mathematical prediction. You see, when Uranus was discovered and astronomers were plotting its orbit, they noticed that Uranus wasn't following their models. From the perturbed orbit of Uranus, Ebon Leferrier in 1846

concluded that there must be another undiscovered planet, and he predicted where it should be, and remarkably, Johann Gale was able to find it only a degree away from the predicted point. Triton, Neptune's biggest moon, was discovered a few days later. But since then, Neptune has been poorly understood as its distance from Earth and very much,

very small apparent size meant it couldn't be studied from ground-based telescopes very easily. It wasn't until 1989, when Voyager 2 arrived, that huge amounts of information about the planet became available. Suddenly, we could see what the planet looked like, confirmed that it had planetary rings, and discovered a lot of previously unknown moons. But let's get to today. What do we know about this planet now? Since Pluto's demotion to not a planet status, Neptune is the eighth and furthest planet from the sun.

It orbits at 30 astronomical units from the sun on average, which means it's 30 times further than the Earth's orbit from the sun. 30 astronomical units, in other words, is 4.5 billion kilometers. And from that, you can see why it would take a space probe, using current technology, 13 years to reach Neptune. 4.5 billion kilometres is a considerable distance. Because of this long orbit, it takes a huge 165 years to orbit the sun once, which means we've only seen one Neptune's year since its discovery. This distance from the sun means the average temperature in Neptune's atmosphere is very cold, minus 201 degrees Celsius.

Its axle tilt is 28 degrees, meaning it's axle tilt is 28 degrees, meaning it's. it's similar to Earth and Mars, which have 23 degrees and 25 degrees respectively. This means it has seasons similar to Earth and Mars too. The big difference being, these four seasons last 40 Earth years each. At this moment in time, the Southern Hemisphere is experiencing spring. During this spring, the Southern Hemisphere receives more sunlight and appears brighter. This increase in brightness is actually quite noticeable, which strange, as you would have thought that because the sun is 900 times dimmer on Neptune than on Earth, from that distance, it wouldn't make much of an impact.

But even if it is only a small impact, it makes an impact nonetheless, and the increased sunlight levels in the southern hemisphere warm it up by about 10 degrees Celsius compared to the rest of the planet. This comparably higher temperature releases frozen methane into the stratosphere, causing is increased brightness, whereas elsewhere on the planet, it remains frozen and stays deeper in the troposphere. Just a quick recap of the spheres of a planet, the troposphere is the lowest atmospheric level, followed by the stratosphere. Above those layers are the mesosphere, the thermosphere, and then the

exosphere. But that's a very interesting topic in itself, and we'll save it for another video. If you look at the weather on Neptune, it actually has the fastest wind speed of any planet. With wind speeds blowing westward on the equator, reaching a staggering 2,160 kilometers per hour, nearly a supersonic flow. And interestingly, most winds travel retrograde to the rotation of the planet. Bands are also formed on the planet, as well as colossal storms. When Voyager 2 passed by the planet in 1989, it saw the great dark spot, storm about the size of Earth passing through its atmosphere. Voyager also saw the smaller storm known

as the small dark spot south of its big sibling. As Voyager 2 approached Neptune, this smaller storm changed in shade from dark to light. When Hubble was launched, astronomers were curious to see the fate of these storms, to see if they were a permanent feature like Jupiter's great red spot. But when Hubble was pointed at Neptune in 1999, these storms had completely disappeared. and storms have come and gone ever since. Giant, bright, high altitude clouds also come and go. But why then doesn't Uranus, which is very similar in composition and size to Neptune, also have such a blustery atmosphere?

Don't get me wrong, wind speeds on Uranus are fast too, but it doesn't compete with Neptune at only 900 kilometres per hour. Can all this only be due to interactions with the sun and its seasons? Something else must be at play here to explain the extremes in weather. The answer may lie deep beneath Neptune's surface. I mentioned that Neptune is the furthest planet from the Sun, so you would have thought it's also the coldest. But actually, Uranus is the coldest planet in our solar system.

Neptune radiates heat from within, whereas Uranus radiates hardly any excesses. heat at all. This could be because a large Earth-sized body crashed into Uranus billions of years ago, which depleted all of its primordial heat. Astronomers now theorized that the more active weather on Neptune might be due, in part, to this higher internal heat. What is Neptune actually made of then? Its internal structure and atmosphere is thought to be very similar to Uranus.

This atmosphere is composed of mainly 80% hydrogen and then 19% helium, with very small amounts of methane. It's this methane though that gives Neptune its blue color, although it's a darker shade of blue compared to Uranus's cyan. Again, like Uranus, there is a liquid mantle of water, ammonia, and methane isis surrounding the core. And where the core and the mantle meet, the pressure is so great that the methane may break apart and diamonds are formed under the pressure.

Likely not diamonds as you or I know, but there could be a liquid carbon ocean with solid diamond bergs floating in it, and diamonds raining down through the mantle like hailstones. This is just a theory though, as technology has only recently started to recreate such pressures. Around the core of Neptune, it's thought to be 7 million bar, or 700 gigapascals, which is about 7 million times the pressure of Earth's atmosphere at the surface. Even the two ice giants magnetosphere share similarities. Neptune's magnetic field is offset 47 degrees relative to its rotational axis. When Voyager 2 discovered this about Uranus, the first theory was that it had something

to do with its unusual axle tilt, but then it found the same thing out about Neptune, which has a more normal axle tilt. So the current theory is that the magnetic field is that the magnetic field is a very unusual axle tilt. either not generated in the core, but rather by an electrically conducting liquid mantle, or that the mantle deflects the magnetic field from the core, which gives it this weird offset in relation to its rotational axis. Every planet in the solar system hasn't actually got a perfectly aligned magnetic field, even Earth's magnetic north, is different from where the North Pole actually is, but it's only Uranus and Neptune that have such a tilted magnetosphere.

do exist on Neptune too, but they are different from what you might expect, as they are extremely faint due to particles not getting as charged from the sun, and because of the direction of the magnetosphere, they are mainly type B aurora, or saar arcs. Earth gets these too, but they are not visible and you need scientific instruments to know that they are there. They could be stretching across the whole sky without you actually knowing about it. Another difference with the The Tsar-Arks of Neptune is that they are not only found around the poles, but rather are around the mid-latitudes of the planet. Zooming out from Neptune a bit, we come to its ring system.

Like all other gas giants, Neptune does have a ring system, although it is extremely faint, as it is not as dense and is extremely dark in colour. If you have these rings against the black backdrop of space and also have them be this far away from the sun, then they are very hard to see. But there are five known rings in all, and they are named after people involved in the discovery and research of Neptune. The innermost is the Galle ring, which is very faint and very wide at 2,000 kilometers. Next is the first bright ring, Leferrier. Although it's bright, it's only 113 kilometers wide. Next, and connected is the Lasso ring, a very faint band 4,000 kilometers across.

On the edge of this ring is the Arago ring. It is slightly brighter than the Lasso ring and less than 100 kilometers wide. Lastly is the outmost and the most research ring, the Adams ring. It is only 35 kilometers wide, but is one of the brightest rings. It is particularly interesting as it is slightly inclined and has bright up. arcs in it. These arcs have been quite stable since they were discovered in 1980, but usually planetary rings are uniform throughout.

These arcs must be material clumping and clustering up within the ring, but the reason for this is currently unknown. Lastly, I want to talk about the moons. Neptune has 14 known moons which are named after water deities in Greek mythology. The most famous and the largest by far is the moon triton. which actually contains most of the mass of all of Neptune's moons put together. I personally think it is one of the prettiest moons in our solar system, as it has amazing patterns and is burned orange colour.

What is most interesting about Triton is the fact it orbits in retrograde, and also at an inclination to Neptune's rotation, which implies it is probably a captured object and not something that was formed alongside the planet. might be the cause of the rings of Neptune, as it would have disrupted the orbits of moons, possibly causing them to collide and break up into what is now the rubble of the rings. Triton is even bigger than Pluto, and also has a tenuous atmosphere. Voyager 2 even saw faint clouds on its flyby of the moon. The next biggest moon is Proteus, which is a little irregular in its shape.

Normally, we only see this on smaller objects like asteroids, but Proteus is actually bigger at 400 kilometers across than the spherical moon of Saturn, Mimus. Why it is not a sphere is explained by past collisions of things hitting the moon, leaving these massive craters which you see. The inner regular moons orbit around the rings, some acting as shepherd moons. The outer, irregular moons are all likely captured moons. Some of the irregular moons orbit prograde, and others retrograde. The outermost moons of Neptune are Samath and Netto, and are the furthest out satellite

of any planet that we know of to date. They take a massive 25 years to orbit Neptune only once. This is because Neptune has a very large hill sphere, the hill sphere being the sphere in which the planet's gravity overcomes the gravity of the Sun. It has such a large hill sphere because it's already so far from the sun. The sun's gravity has less of an influence around Neptune than at the biggest planet, Jupiter. Well, thank you for watching.

Did you learn something interesting about Neptune today? What mysteries would you like to see solved? We're still working our way through remastering the planets in our Solar System series. What planet would you like to see us do next? Let us know in the comments below, and I'll see you next time. watching. And thanks to our crew of astromnaughts over at Patreon, who help us make science knowledge freely available to everyone. Chasing the algorithm can be hit and miss sometimes, so your contributions help us keep making the content we love. And if you want to join the

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