Astrum Space - You've Never Seen the Gas Giants Like This

Episode Date: October 12, 2026

In this Astrum compilation, we’re exploring the gas giants of our Solar System. From swirling storms and breathtaking aurorae, to surprising discoveries in their cores - we’ll dig into the discoveries and stunning high resolution images that reveal what’s going on deep inside these behemoth planets. ▀▀▀▀▀▀A huge thanks to our Patreons who help make these videos possible. Sign-up here: ⁠https://bit.ly/4aiJZNFThe Astrum book is still available in the US! Get your hands on one here: ⁠https://astrumspace.co/⁠

I don't know where the time has gone, but it's now been three years since Juno arrived at Jupiter. During this time, it has been collecting valuable and insightful data about the largest of our neighbour planets. It has recently completed Peridjov-21, or its 21st polar orbit, out of a total of 35 planned orbits, which means we are now well past the halfway point of this mission. Some of you veterans to this channel will remember the video I made about Juno at its one year mark. But what has it discovered since then?

And has it disproved some of the assumptions we had about Jupiter from before it arrived? I'm Alex McColgan and you're watching Astrum. And together we will go through everything Juno has discovered and seen around Jupiter so far. There was some skepticism about whether Juno would last this long due to the intense radiation around the planet. But Juno is currently in good health. This polar orbit takes it very close to the planet, only 4,000 kilometers above its atmosphere,

meaning it avoids most, but not all, of Jupiter's plasma torus, or this region of extremely energized particles, particles which have been trapped in place by Jupiter's powerful magnetic field. But thankfully, Juno quickly discovered that the radiation where it orbits was a lot weaker than initially expected. This means that even the camera is still operational, which was one of the first instruments expected to go. Juno completely surprised scientists, though, by discovering another small and less powerful

radiation belt right above the equator, which hugs the planet tightly. So far, the mechanisms behind this radiation belt are unknown. However, although the radiation exposure hasn't been as bad as scientists expected, due to With the nature of Juno's orbit, every passing Peridjov takes it more and more into the main radiation belt, meaning Juno certainly can't last forever. And Peridove 35 is currently when mission controllers believe the mission will be forced to end, whereupon they will crash Juno into Jupiter to avoid any future collisions with Europa. The charged particles in the Plasma Taurus come particularly from the volcanic activity

of Jupiter's largest moon, Io, which blasts particles in the plasma, into orbit around Jupiter. Just to give you an idea of how volcanically active Io is, this was New Horizons view of Io as it passed by Jupiter on its way to Pluto, the Tavashhtar volcano in full eruption. Juno has also had a look at I.O. in the infrared, the hot spots indicating where volcanic activity is occurring. I.O. ejects one ton of particles into orbit around Jupiter per second. As Iyo travels through the plasma torus and interacts with Jupiter's magnetosphere, this causes

a flux tube to exist between the planet and the moon. A flux tube being an electric current that travels along a cylindrical tube of magnetic field lines. It is very powerful. It can develop 400,000 volts and 1 million to 5 million amps of current. Juno was able to get very accurate readings of the flux tube during its 12th orbit, as it passed directly through it. No, this didn't fry the spacecraft, as the flux tube has a large diameter and so it isn't concentrated enough to do damage to the craft. Also, Juno was in

and out in a matter of seconds. Now, Juno is a massive spacecraft, 20 meters in diameter. And it really has to be, as it is a solar-powered spacecraft and only gets 4% of the sun it would do around Earth. This means even though these panels are huge, it can only generate just above 400 watts. But you'll also notice that this design, paired with the fact that Juno rotates, makes it look a little like a fidget spinner. This isn't just to make a pretty spinning spacecraft. Juno was specifically designed to detect various fields and particles around Jupiter, and having

a spacecraft with a large spinning radius helps with that. This is particularly evident with this instrument here. The magnetometer found at the end of one of the solar panels, tasked with mapping out Jupiter's magnetic field. Through Juno's data, we now have a highly detailed map of Jupiter's magnetic field, which is only getting more accurate with every passing orbit. As expected, Juno confirmed that Jupiter has a dipole-like magnetic field, although it is not very aligned with the rotational axis. What was very interesting, though, is that scientists discovered something called the Great

Blue Spot, a region on Jupiter where the magnetic field is very concentrated. Comparing Juno's magnetic field data with previous Jupiter missions, like Pioneer, Voyager, and Galileo, has also revealed a first for the solar system. Jupiter's magnetic field structure has been found to change very gradually over time, which is called secular variation. Interestingly, this was most apparent around Jupiter's great blue spot. This variation is thought to be driven by a region right at the base of Jupiter's atmosphere, which we'll get to in a bit. A combination of the powerful magnetic field and the charged particles in the plasma torus means that Jupiter has the brightest aurora in the solar

system, with a radiant power of 100 terawatts. Like Earth, aurora appear as a light. as bands around the North and South Poles, but unlike Earth, these aurora are mainly visible in the ultraviolet, and are mainly produced from alternating currents, not direct currents. When Juno measured the power generated from the direct currents in Jupiter's magnetosphere, it was nowhere near enough to account for the brightness of the aurora, leading scientists to speculate that the remainder of the power is coming from alternating currents. At this time, it is believed that these alternating currents are produced because of the turbulence in the magnetic field.

Especially at the North Pole, the magnetic field lines are much more complex, which interferes with a direct flow of currents. This is evident when comparing the North and South Pole Aurora. At the north, the Aurora is much more dispersed, looking more like filaments and flares. Whereas at the South Pole, where the magnetic field lines are smoother, the aurora seems to be more structured and round. What you will also notice is this bright spot and tail in the aurora. This is visibly where the I.O. flux tube meets the planet.

What is less apparent though are these other spots. These are from the other large moons in the Jovian system, Europa and Ganymede. So while not as powerful as IOS flux tube, these other moons have their own flux tubes connecting them to the planet too. The magnetic field of Jupiter brings us nicely to one of the main science goals of Juno. To figure out the interior of Jupiter. Since Juno arrived, previous theories have had to be completely thrown out the window by the data it is collected.

Previously, it was thought that there was a solid core, and then a sharp cutoff line between the core and the next layer, the metallic hydrogen layer. The cloud layer was then only thought to be a few hundred kilometers deep at most, but But based on the Juno data, the atmosphere of Jupiter extends to 3,000 kilometers down, and beneath this is an ocean of metallic hydrogen going all the way down to the center, and even if there is a core, it is very fuzzy, potentially mixing up with the metallic hydrogen layer. So actually, to call Jupiter a gas giant is a bit disingenuous, as 80 to 90% of its radius is believed to be a liquid now, or technically an electrically conducting plastic.

perhaps similar in appearance to liquid mercury. Here the pressure is so great that the hydrogen doesn't retain its molecular structure with two combined protons and electrons, and instead they separate, meaning positive and negative charges can move about becoming an electrically conducting substance. We say believe, as we haven't been able to recreate metallic hydrogen in lab conditions yet, the pressure needed is millions of times greater than the atmospheric pressure of the pressure of Earth. Although, we assume this must be the case due to Jupiter's powerful magnetic field. To create a magnetic field of this strength, the dynamo must originate in an electrically conducting

substance. It can't be a denser metal-like iron in Earth's core, because Jupiter doesn't have the density for that. In fact, based on its density, we know that it must be made primarily of hydrogen and smaller amounts of helium, very similar in composition to the Sun. Another factor for the strength of the magnetic field is due to the rapid rotation of Jupiter. One day on Jupiter only lasts about 10 hours. Various forces from this stir the liquid up, which generates the dynamo. It is the rotation of the magnetic field from which we can measure a day on Jupiter, as simply viewing Jupiter's visible bands couldn't give you a definitive result.

And this is why. You'll notice these bands look very peculiar, moving in opposite direction. directions from each other at different speeds. But this isn't so unusual if you consider the invisible jet streams on Earth. What is striking though is the colors and turbulence found in these bands. So let's try and understand what's going on from examining these Juno images. The cloud layer you are seeing here is the ammonia cloud layer. Some are white.

These represent fresh clouds, likely only recently pulled up for the cloud layer. from the deeper parts of the atmosphere. On the other hand, while the red colours you see are also ammonia clouds, these clouds have interacted with UV light from the sun. Think of it like a photochemical smog, the reddish smog you see in summer over large cities. The colouring substance isn't exactly known, but simply put, the longer it is exposed to the sun, the redder it gets. Interestingly, though, comparing these bands to what you see at the poles, you'll notice it

is a lot bluer here. This could be because UV light doesn't reach here as easily compared to the equator. Looking closely, you'll also notice what is known as pop-up clouds. Initially these were thought to be maybe water ice clouds, but they could be ammonia clouds too. They are potentially the precursors for thunderstorms on Jupiter. The radio wave instrument on board Juno does detect lightning on Jupiter, however, these storms are interestingly more localized towards the poles than at the equator, and more towards the North Pole than the South Pole.

The cause for this is unknown. Looking closely at Jupiter, you'd be hard-pressed not to notice the stunning vortexes and storms across the planet. Juno has had the opportunity to orbit directly over the Great Red Spot, where it discovered something very interesting. It was known that the Great Red Spot rises high above the cloud deck, but what scientists didn't expect is how deeply it penetrates Jupiter's atmosphere. The instrument on board Juno designed to peer into the atmosphere has a range of 350 kilometers, and it seems the Great Red Spot extends down even further than that. Also interesting

is that the spot is cooler than the surrounding area, up until the depth of 80 kilometers, and beyond that, it actually gets warmer than the surrounding area, this heat perhaps driving the storm. It has been theorized that the Great Red Spot is a permanent feature on Jupiter, but we've only had about 400 years to observe it so far, a mere blink in astronomical timescales. Looking over the poles, other possible permanent features have been observed. In contrast to Saturn, which has a hexagon on one pole, and a single vortex on the other, Jupiter has five vortexes around the South Pole and eight around the north. It's hard to say exactly how permanent these storms are, as Juno has only been there for three

years, and Juno was the first time we have really been able to have a good look at Jupiter's poles, but they have been reasonably constant throughout that time. Under the ammonia cloud layer, it's thought to be a water ice cloud layer, although this has not been confirmed, as this layer hasn't actually been seen yet. This is one of the science goals of Juno, though, and it has several microwave detectors to try and find this elusive substance. Jupiter generates heat from within, which can be seen through an infrared camera, the densest parts of the cloud layer blocking some of the heat from being visible.

Similarly, Jupiter also emits microwaves, which hypothesized water clouds would absorb, so in theory, Juno should be able to detect where the water is present in Jupiter's atmosphere by searching for where Jupiter's microwaves aren't visible, although this data has either not been released or nothing has been found yet. All that being said, Juno still has a while to go with this mission, and no doubt the data it collects will be examined for years to come. Our understanding of Jupiter is gradually increasing, and with this knowledge comes a better understanding of how our solar system formed, and also that of other solar systems with Jupiter-sized worlds.

And who knows, maybe Jupiter will surprise us a few times more yet. As promised, here's another look at this image I mentioned in the Saturn video. Find that video here if you haven't seen it already. As I said, I was going to go into a lot more detail, as there's so much to talk about in just this one image. So firstly, to give you a sense of scale, this image is about 400,000 kilometers across from edge to edge. I think you'll agree that this is one of the most beautiful images that NASA has ever released.

In truth though, this image has also been enhanced to make fainter objects brighter in comparison to the very bright objects around them. NASA says this image, as you see it, is now a balance between reality and beauty. But know that nothing has been added at all, only brightened. Now normally this outer bright blue ring is not visible on most pictures of Saturn. The reason we see it now is because the sun is directly behind Saturn, and being in the planet's shadow means fainter objects become more apparent. The blue color of the ring is due to diffraction in much the same process which makes

the sky blue. The particles in this ring are fueled by this little 500 km wide moon here, Enceladus. This moon has a lot of geysers shooting particles into space. Captured by Saturn's gravity, these particles remain in orbit and form the E-ring. In fact, you can see these geys as blast in jets of particles, even in this picture. A close-up of Enceladus looks something like this. Seen in ultraviolet, visible and infrared lights, it's an incredibly pretty moon, with relatively few surface craters, which means it must be active with water volcanism to renew the surface.

In fact, it's covered in a very thick layer of ice, which makes it one of the most reflective objects in the solar system. These water or cryovolcanoes blast about 200 kilograms a second into space at speeds of over 1,600 kilometers per hour. It's thought that the liquid water ocean is under the ice, particularly near the South Pole, and it's under enormous pressure, hence why these cracks are formed and water is escaping. Also in the vicinity of the E-ring are the moon's Tethys and Mimus. Tethys is the biggest moon of Saturn in this picture, being over-werex.

1,000 kilometers across. It's not too colourful as you can see and has huge impact craters in rift valleys. The biggest crater in particular makes it look like a giant eyeball, and the biggest fault line is a massive 2,000 kilometers across. Like Enceladus, it's also covered in ice, and this ice makes it the second brightest moon of Saturn. Mimus on the other side of the picture, here can be seen creating a long shadow through Saturn's E-ring. This is the moon that has been nicknamed the Death Star due to its similar appearance. It's about 400 kilometers across and is as well thought to be made up mostly of water ice. All right, let's zoom out again so we can see the rings of Saturn.

The next closest ring to Saturn after the E-ring is the Plenny Ring. It is very faint, but if I zoom in, it's this band through the center of the screen. screen here. It's named after the tiny Pelleni moon, which the Cassini probe actually discovered. Plenny itself can't be seen in this image as it's less than 3 kilometers across, but it's thought this ring is the residual remains of meteorite impacts with the moon. The next ring is easier to see, the G ring. And the next is the Janus or the Epimetheus ring. Like the Pelani ring, it is made up of the particles which have been knocked off the two co-orbital moons, Janus and Epimetheus. While still very tiny moons, they are big enough to be

seen in this image. Janus is here and epimetheus is here. Janus is about 200 kilometres across, and epimetheus only 130 kilometres across. And when I say they are co-orbital moons, I really mean that. Janice's mean orbital radius is roughly 50 kilometres less than epimetheus. But this could change every time the moons catch up with each other, which happens about once every four years. They last switch positions in 2006. The next ring we see is the bright F-ring, which houses the two shepherd moons, Prometheus and Pandora. I spent some time already discussing Prometheus in the Saturn video, so I won't do it here. But here you can see it tucked away just inside the F-ring.

Pandora is right on the other side. Pandora is slightly smaller than Prometheus at 81 kilometres across, but is found on the outside of the F-ring instead of the inside. Prometheus and Pandora can also get close to each other, and whenever that happens, they perturb each other's orbit. They are called Shepard moons because they keep the F-ring narrowly confined, sometimes even stealing some of the material themselves when they get too close. To finish talking about the rings, we have the A, B, C and D-ring. If you do want to find out more information about that, again have a look at the other Saturn video. Finally, let's look at some of the other planets we can see here.

Yes, even though they are millions of kilometers away, we can still see some of the inner solar systems planets. Mars is just above the E-ring here. Next is Venus situated between the Pelleni and G-ring. And finally, here we are on Earth, these bluish few pixels. That pixel jutting off the side of Earth is actually our neighbor the moon. Uranus, the second farthest planet from the sun, and the long-suffering butt of the joke. Yes, let's get that out the way.

This oft-forgotten orb, rarely lauded like its larger cousins, Saturn and Jupiter, rolls around the solar system on its side. It has only been visited once, and even that was fleeting. The Voyager 2 spacecraft sped past on the 24th of January, 1986, with just a few hours of up-close observations. For the last 40 years, this has been the foundation of what we know. No other spacecraft have even been close. But that doesn't mean new discoveries have stopped.

Technological advances in telescopy and fresh takes on old Voyager 2 data have revealed a raft of remarkable new insights, some of which might rewrite the textbooks. And just in time, there's a perfectly aligned launch window opening in as little as five years. Whether or not we'll make a trip back to the planet is yet to be seen, but as we approach such a critical decade for revisiting Uranus, it's time to get back up to speed with this forgotten world and unveil the latest findings. I'm Alex McColgan and you're watching Astrum. Join me as we reconnect with our old friend Uranus

to explore its mysteries, old and new. We'll delve into Voyager's back catalogue and show that sometimes new discoveries don't need new data. Uranus is the seventh planet from the sun, and since its discovery from William Herschel's backgarden in 1781, only 2.9 Iranian years have passed Each lasting 84 Earth years, the next new year is approaching in 233. This strange world is perhaps best known for its near horizontal tilt.

Its spin axis is angled at 97.77 degrees to its orbital plane, so it essentially rolls its way around the sun. To put that in context, Neptune's axis, at 28 degrees, is the next highest. This gives Uranus the most extreme seasons in the solar system. Each pole faces the sun continuously for 42 years of polar day, followed by 42 years of polar night. This was pretty much all we knew about Uranus as 1985 came to a close. We guessed it might be an ice giant and were aware of five moons and a ring system, but

essentially this planet was a mystery. In 1986, Voyager 2 arrived, flying past on its way out of the solar system. Almost instantly, numerous discoveries were made. This enigmatic planet was revealed to be even colder than expected, challenging our fundamental ideas of how planets form and evolve. At minus 224 degrees Celsius, Uranus's atmosphere holds the record for the coldest temperature on any planet in the solar system. Voyager 2 also found a magnetic field tilted in a way we had never seen before.

Eleven new moons and two new rings. Its iconic imagery showed a calm and eerie blue-green world. But recent observations and research have built on this picture, refining and in some cases redefining our understanding of this sideways planet. What's more, returning to Uranus has been marked as the highest priority in NASA's planetary science program for the next decade. With this renewed interest, let's dive into some of the most remarkable findings of recent years.

Uranus is four times wider than Earth, with a diameter of 51,118 kilometers, and a mass that's 14.5 times greater than our planets. These parameters can be used to calculate its gravity, which for Uranus is a comfortable 8.7 meters per second squared, about 89% of the gravity we experience on Earth. Grouped with Neptune as an ice giant, Uranus is believed to have a rocky silicate core, likely much smaller than Earth's, surrounded by a deep mantle of water, ammonia and methane ices. A misleading term, since its inner temperatures can soar to nearly 5.

5,000 degrees Celsius, it's much more like a fluid ocean than ice as we might think of it. This extreme heat and the immense pressure at the base of the mantle, up to 600 gigapascals, can break down the abundant methane molecules and compress the resulting carbon atoms to form diamonds. A captivating picture. But is it right? Voyager 2Data initially said so, but new modelling, public, but new modelling, public, but it's a captivating picture. in the journal Astronomy and Astrophysics in 2025 suggest that it's perhaps not quite

the whole story. The researchers, Lukomorff and Ravit Hellerd of the University of Zurich took an agnostic approach, generating random models of the interior contents of Uranus and its ice giant neighbour Neptune. These were then compared to observational data and narrowed down accordingly, with one major surprise, The results show that the possible composition of Uranus is much more varied and complex than previously assumed. For example, the rock to water ratio could be as low as 0.04, making the planet almost entirely water, or as high as 3.92, making it the complete opposite, namely predominantly rock.

This means that Uranus and Neptune have the potential to be rock. Rock giants instead of ice giants. What's more, if the rock dominated option holds up, it challenges our fundamental models of solar system formation. But as the authors attest, this work is theoretical. We'll only know for sure by visiting the planet again. More on that later. Continuing out from the rocky core, the outermost layer of Uranus is comprised mostly of helium,

and 2% methane, with a cloud layer on top. Methane absorbs red light, leaving behind the distinctive blue-green hues Uranus is known for. Voyager 2, during its 1986 flyby, found Uranus cold and tranquil, with only faint clouds and a dark spot. But this veil of tranquility has been lifted, thanks to telescopes, including Keck, Hubble, and the James Webb Space Telescope, revealing a hidden dynamism. In 2014, the W.M. Kek Observatory in Hawaii detected eight huge storms on Uranus's northern hemisphere. Such was their intensity that, for the first time ever, amateur astronomers were able to see details in the planet's atmosphere. The largest white spot in this near-infrared

image from the WM. Kek telescope is the brightest storm ever seen. on the planet at this wavelength of 2.2 microns. It's around twice as bright as anything seen before. It accounted for 30% of all the light reflected by the planet in this observation. The cloud rotating interview in the lower right also grew into a storm, spotted by amateur astronomers at visible wavelengths. Observations by Hubble over a 20-year period found that the polar regions become noticeably more meteorologically active as the planet moves through its uniquely long seasons.

Despite the study lasting two decades, Uranus was in northern spring for the entirety of this time, with the sun starting at equinox over the equator and moving towards the North Pole as it near summer. The Hubble team's results, published in 2025, found bright cloud activity when the sun was closest to the equator, with peak activity observed near the 2007 equinox. The haze and cloud structure changed dramatically over the four observation windows, with aerosols in the atmosphere thickening at the North Pole as the planet approaches the summer solstice, which it will reach in 2030. You can see this accumulation of aerosols in these images.

The North Pole changes from dark in 2002 to highly reflective in 2020, 2022, with complementary darkening of the South Pole as it moves into winter's shadow. Together this shows that sunlight is directly altering the formation of haze and clouds in the uranium atmosphere. The Hubble observations also identified circulation patterns that drive seasonal shifts, uncovering evidence of atmospheric gases sinking at the poles and upwelling elsewhere. The persistence of this downwelling and the changes in climate are driven. by Uranus's extreme axle tilt. It's the only planet that receives more energy from the

sun at its poles than the equator, and it experiences the most radical seasonal changes in the solar system, but it's not just the sun's light that drives this. A team at Imperial College London found that the Uranian thermosphere is also heated by the solar wind. Again, this is the only place in the solar system where this seems to happen. But as the solar wind's pressure has been dropping since 1990, Uranus has been cooling alongside it. Despite these remarkable findings, Uranus is still significantly less volatile than its cousins, Jupiter, Saturn, and Neptune. They are famous for their vast storms and swirling atmospheres, and that's because these

are driven by internal heat left over from the formation of these gas giants. It's the slow release of this energy that creates the turbulence they are driven by internal heat left over from the formation of these gas giants. they are so well known for. Which brings us to one of Uranus' great mysteries. Why is it the coldest planet in the solar system? What happened to the heat left over from its formation? Two recent studies, both published in 2025, revealed that Uranus does have its own heat, but only releases a tiny fraction of it, emitting about 15% more energy than it receives from

the sun. By comparison, its neighbour Neptune emits more than twice as much energy as it receives. This extremely low heat flux is more than just another oddity for the hotball planet. It hints at a violent past, with consequences not just for its climate and weather, but its fundamental characteristics and even its moons. Uranus' near horizontal 97.77 degree tilt has long been thought to be a consequence of a violent historical collision, but we've only recently started to uncover the full picture. High-resolution computer simulations, published in the Astrophysical Journal in 2018 by

Jacob Kegaris at Durham University and his colleagues, have provided a more detailed picture of how this could have happened and the far-reaching influence it had for the planet. Their study ran more than 50 different impact scenarios in an attempt to recreate the Uranus we recognized today. The result confirmed that three to four billion years ago, a young Uranus was most likely dealt a glancing blow by an object two to three times the size of Earth, probably a proto-planet made of rock and ice. The impact would have occurred over a remarkably short period. In just a matter of hours, enough force would have been delivered to reorient Uranus's axis, knocking it to its side, and it set in motion a series of events that created the planet we

see today. The simulations show that most of the protoplanet was deposited in Uranus, creating a hot, high entropy shell in the icy interior. Highly disordered, high entropy materials don't conduct heat well, so this layer acts like an insulation, trapping heat deep inside the planet and helping to explain the low heat flux and extreme coldness we see on your air. Uranus today. This unique interior structure may also help explain Uranus' profoundly weird magnetosphere. Usually, these invisible magnetic shields originate from the geometric center of a planet, its core, but that's not the case here.

Voyager 2's original flyby discovered that its magnetic field is tilted by almost 59 degrees from its rotational axis, and offset from the planet's center by a thick, third of the planet's radius. This magnetic misalignment creates an asymmetric magnetosphere, with a magneto tail that corkscrews into space for millions of kilometers. When Voyator 2 flew past, the magnetosphere actually appeared to be much smaller than thought, and this has baffled scientists for decades. Recent reanalysis of the original data, led by Jamie Jasinski at NASA JPML and published in

nature astronomy in 2024 finally provided an answer. When Voyager arrived, it was in the midst of some violent space weather that compressed the planet's magnetic field, something NASA couldn't have planned even if they tried. The new study instead suggests that the planet's magnetosphere is actually even larger, and more active and variable than initially thought. The reason for such a strange magnetosphere isn't fully understood, but it could be that fields don't originate from the planet's core at all. Rather, they come from the convecting mantle, influenced by the deposits left by that ancient collision billions of years ago.

For us at least, this has had one serious upside. The off-kilter magnetosphere leads to stunning, sprawling auroras that do not align with the poles like on Earth, Jupiter or Saturn. These phenomena have been imaged by Hubble in both the visible and ultraviolet parts of the spectrum, and by studying a decade of these images, scientists recently calculated Uranus's rate of rotation with 1,000 times greater accuracy than before. Their technique revealed the planet completes a full rotation in 17 hours, 14 minutes and 52 seconds, 28 seconds longer than the estimate obtained by Voyager 2. And I simply couldn't miss out. including this stunning representation. It shows infrared auroras, which, after 30 years of study,

were finally detected on Uranus in 2023 using the Keck 2 telescope. But the consequences of Uranus' violent past haven't ended yet. At the time of impact, its largest moons hand-formed. Instead, the planet sat amid a disk of stuff, for lack of a better word, with the impact jettisoning further rock and ice into orbit around the planet. As this started to clump together to form the five largest moons, Uranus' new axle plane acted like a gravitational tidal wave, pushing them to the same tilt. As of now, Uranus has 29 confirmed moons, two more than when I last made a video about the planet. Moon 28 is currently called by the rather catchy title S-2020 U-1 and was discovered

in 2023 by Scott Shepard using the Las Campanus Observatory in Chile. The most recent edition, its 29th moon, was made in February 2025 by using the James Webb Space Telescope's Neacam. Designated S-2020-U1, it is yet to be officially named. Let me know if you have any great suggestions for names in the comments. This startling array of moons is divided into three categories. 14 inner moons, 5 major moons, and 10 irregular satellites. Romantically, they are named after characters from English literature. The major moons, Miranda, Ariel, Umbriol, Titania, and Oberon feature diverse compositions

dominated by water ice and rocky material. published in 2025, it was a very busy year for Uranus scientists, hint at possible differentiated interiors, with liquid ocean sandwich between rocky cores and icy mantles, which of course raises the tantalizing question of whether they are habitable for life. But again, only an actual visit could tell us that. Like its immediate neighbours, Saturn, Jupiter and Neptune, Uranus has a ring system them. They are aligned with its tilted spin axis, so during Voyager 2's approach 40 years ago, they appeared almost like a bullseye. The rings are very young by solar system standards, thought to be a mere 600 million years old, and they're believed to have been formed by the

breakup of a small moon colliding with a meteorite or a comet. Their most remarkable feature is how dark they are. With an albedo of less than 2%, they are made. made of the darkest material in the solar system. What exactly that is? Is of yet unknown? But scientists think it could be particles of water ice mixed with organics or methane ice singed black. Against Uranus' bright exterior, the rings are really difficult to discern, so much so that

they were discovered by accident in 1977 thanks to a star occultation, an event in which Uranus moved in front of a star. and the subsequent dimming confirmed the presence of the rings. Thirteen rings have now been imaged thanks to Voyager 2, as well as the advanced teloscopy of Hubble, Kek2 and the James Webb. They range from a few kilometers wide to roughly 100 kilometers wide, and it's unclear why some of the rings are kept so narrow. Shepard moons may help maintain the structure of some of them,

but for most the mechanics remain obscure. Excitingly, a rare stellar occultation happened again in April 2025, with Uranus passing in front of a star about 400 light years from Earth. This led to a coordinated effort to observe Uranus like nothing done before. Led by planetary scientists at NASA Langley, an international team of over 30 astronomers using 18 observatories, simultaneously trained their attention on Uranus for about an hour. It was the largest campaign ever organized and the largest simultaneous observation of Uranus since Voyager 2's 1986 flyby.

The nature of an occultation is perfect for studying Uranus's atmosphere and rings. Atmospheric findings are yet to be released, but the precision of the ring data, specifically the timings of each occultation, have allowed scientists to determine where Uranus is in its orbit, its position by around 400 kilometers. This is critical information for sending a physical mission, but I'll talk more on that later. This unprecedented coordination is just the beginning. Over the next decade, Uranus is set to pass between Earth and the galactic center of the Milky Way, prime opportunity to carry out further occultation studies, with the best ever conditions lined up for 2031.

The last few years have been a flurry of publications and activity. Looking at you, 2025, focused on the strange seventh blue-green, sideways planet, revealing it to be a dynamic world with a storied past and enigmatic features. So much has been learned since William Herschel stood in his back garden, looking through a homemade telescope, and that's despite Uranus and its neighbor Neptune being the least visited planets in the solar system, even more discovery lies ahead still. The 2023 Planetary Science Decadal Survey has made a Uranus orbiter and probe mission NASA's top planetary priority, and the Chinese National Space Administration have also proposed

a mission to the planet with Tianwen 4, with the possibility of another visit visit on the horizon, scientists will need to look sharp as we're approaching a critical window. 2031 and 2032 are optimal launch opportunities. Thanks to planetary alignments, a future spacecraft could get a gravity assist from Jupiter, shortening the journey by several years. Mission objectives are set to include mapping the planet's gravity in magnetic fields over time, studying the weather systems, and atmospheric composition. characterising rings and investigating the potential habitability of its moons.

So stay tuned. The next chapter of Uranus exploration is being written as we speak. If you were to look up into a clear night sky with your naked eye, what planets would you see? Technically, if conditions were right and you had very good eyesight, 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 icy giants and also the furthest away.

It's a wonder we found it at all. And it is a place of wonders. Gigamous storms that rise and fall, super fast winds that are almost super sonic, icy rings, and enigmatic moons hinting at a violent past. Of all the planets, it's the one we know the least about.

But what exactly do we know about Neptune? I'm Alex McCulligan and you're watching Astrum. Today in this Supercut, we're going to delve into everything you could want to know about Neptune. Let's start right at the beginning with how we found Neptune in the first place. Because, unlike every other planet in the solar system, Neptune was not discovered by merely being spotted with a telescope. Its story is far more intriguing. Neptune is the only planet found through mathematical prediction. It happened in 1846, thanks to Oban Jean-Joseph Leferrier, a French astronomer and mathematician. The Ferrier had been examining the rotation of the

then-7 planets when he noticed that something was off about Uranus. It didn't seem to be moving in line with the theories of gravity proposed by Newtonian physics. Leverier reasoned that the only explanation for this was that there must be a planet out beyond the orbit of Uranus that was perturbing its motion to account for this discrepancy. He did some maths, and then declared that his eighth planet must exist at an exact point in the night sky. The incredible thing was, after hearing his prediction, Leverier's friend, Johann Godfrey-Gale, got out a telescope, searched in that location, and sure enough, discovered the planet Neptune

in a single hour. It was almost exactly where Laverrier had predicted that it would be. Triton, Neptune's biggest moon, was discovered a few days later. But since then, Neptune has been a place of mystery. It orbits at the very edge of deep space. At certain points of its year, it can even be further away from the sun than Pluto, and the only thing found further out the Neptune are icy rocks. The sun is only a 30th of the size in Neptune's sky, and Neptune receives roughly 1,000th of the sunlight Earth does. This dim lighting and vast distance from us means that Neptune couldn't be studied from ground-based telescopes very easily. Neptune is the eighth and furthest planet from the Sun. It orbits at about 30 astronomical units, which in other words

is 4.5 billion kilometers, and means it's 30 times further from the Sun than we are. You can see why it would take a space probe using current technology 13 years to reach Neptune. 4.5 billion kilometers is a considerable distance. Because of this long orbit, it takes a huge, 100,000 165 years to orbit the Sun once, which means we've only seen one Neptune's year since its discovery. All in all, our icy neighbor is certainly difficult to study. It is hard to spot, and the alternative, traveling to it with a spacecraft is not exactly easy either. In fact, only one spacecraft has ever visited Neptune, and that craft was only able to do so by taking advantage of a rare alignment of the planets that It only happens once every 175 years.

That craft was Voyager 2. It wasn't until 1989 when Voyager 2 arrived, the huge amounts of information about the planet became available. On the 25th of January, 1986, Voyager 2 departed Uranus and snapped this wonderful goodbye shot from 1 million kilometers as it set off to its final planetary target, Neptune, the last destination. on Voyager 2's grand tour of the solar system, and after three years of travel at the speed of 54,000 kilometers per hour, Neptune finally came into view.

Here are the first close-up images we ever received of the giant blue planet, passing only 5,000 kilometers above its north pole, the closest of any flybys. Suddenly, we could see what the planet looked like, confirmed it had planetary rings and discovered a lot of previously unknown moons. Neptune's 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 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 is strange, as you would have thought that because the Sun is 900 times dimmer on Neptune than on Earth, from that distance,

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 its increased brightness, whereas elsewhere on the planet it remains frozen and stays deeper in the troposphere. common element in Neptune's atmosphere, making up 80% of it, although the high abundance of methane sitting at 19% is what gives the planet its blue appearance. Voyager 2 measured extraordinary wind speeds in Neptune's atmosphere, with the equatorial winds

blowing at speeds reaching a staggering 2,160 kilometers per hour, nearly a supersonic flow. And interestingly, most wind travels retrograde to the rotation of the planet. These remarkable speeds were yet another surprise and highlighted just how dynamic and ferocious Neptune's weather systems are. This planet is home to colossal storms. When Voyager 2 passed by in 1989, it saw the great dark spot, a storm about the size of Earth passing through its atmosphere. This turbulent storm seemed to be rotating counterclockwise, just like the great red spot on Jupiter, and exhibited winds reaching up to 2,400 kilometers per hour, the strongest recorded in the solar system.

One NASA analyst, Ken Bollinger, commented on the findings in 1989, saying, every day what you see is brand new. Nobody's ever seen it. It's just an incredible feeling. This changes going on constantly on Neptune that has to be. happen very, very fast. 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.

While our knowledge of Neptune's weather systems is limited, it would be more limited still, were it not for Hubble observing them from time to time. 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 other storms have come and gone ever since. The latest one was seen in 2015. It has lasted a few years, but it too is disappearing.

While there is not enough data to speculate how these vortices develop, it could be that Neptune is like Jupiter with bands in the atmosphere. While they won't be as defined or as many as there are on Jupiter, the bands on Neptune would travel at different speeds. This could cause vortices to appear where the bands meet. Once the storm has got going, it can drift around the planet, even between the bands. But once it leaves its power source, it begins to slow. slowly diminish, which is what we have seen.

Interestingly, Hubble is the only program that can monitor these weather changes, as in most light wavelengths they are very hard to spot. Hubble though can probe Neptune and Uranus in the ultraviolet, making these observations possible. 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 a 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 excess 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. 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. The two ice giants magnetospheres also 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 either not generated in the core, but rather by an electrically conducting liquid mantle, or that the mantle

It also 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. Aurora 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 sar arcs of Neptune is that they are not only found around the poles, but rather are around the mid-lust of the planet. However, although they are faint, we recently were able to capture images of them thanks to the powerful near-infrared detection of the James Webb Space Telescope. In March of 2025, Webb released these shimmering images of Neptune's mid-latitude aurorae, shining out across the planet. Interestingly, at the same time, Webb was able to notice a massive temperature drop in Neptune's upper atmosphere.

Its temperature had dropped by hundreds of degrees since Voyager's reading in 1989, almost halving during those intervening few decades. What this means for the turbulent processes taking place within Neptune remains open for investigation. But as Aurora are harder to detect in colder temperatures, this may help explain why Neptune's Aurora remain so elusive. Zooming out from Neptune a bit, we come to its ring system. Up until 1986, scientists suspected the planet might have rings, but couldn't be certain. It turns out that, like all other gas giants, Neptune does have a ring system, although it is very 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. Intriguingly, Voyager 2 identified several partial ring structures or ring arcs within Neptune's ring system. These arcs raised questions about the mechanisms responsible for their formation and stability, since they mainly consisted of incomplete and dusty rings. There are five known rings in all, and they're all named after people involved in the discovery and research of Neptune. The innermost is the Gale ring, which is very much. 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 km wide, but is one of the brightest rings. It is particularly interesting as it is slightly inclined and has bright 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. Firstly, a visit to Neptune wouldn't be complete without talking about its moons. Neptune has 14 known moons, which are named after water deities in Greek mythology. Seven of these moons are regular moons, or in other words, moons that orbit along Neptune's ecliptic with very circular orbits, or orbits with very low eccentricity. After these inner regular moons, we get to the irregular moons, the first of which is

Triton. I personally think it is one of the prettiest moons in our solar system, as it has amazing patterns and this burnt orange colour. An irregular moon is a moon that follows an inclined, eccentric and often retrograde orbit. This by itself is already where Triton is set apart from any other spherical moon in the solar system. It has an irregular orbit. Triton orbits clockwise around Neptune, as Neptune rotates counterclockwise, and Triton orbits at a 130 degree angle to the ecliptic of the planet, although it should be noted that its orbital eccentricity is close to zero. Its orbit is almost perfectly circular. All other large moons in the solar system are regular moons, orbiting the same direction as the

rotation of their parent planet. What this heavily implies is that Triton did not form alongside Neptune, but it is in fact a captured object, specifically a captured dwarf planet. No wonder then that it is by far the biggest of Neptune's 14 moons, comprise in 99.5% of the mass found in Neptune's orbit. But how big is that in scales we can relate to? Well, it is the second largest moon in relation to its parent planet, second only to Earth and its moon. While it is smaller than our moon, it orbits closer to Neptune than our moon orbits Earth, which means it appears about the same size in the sky. It is the seventh largest moon in the entire solar system, and most interestingly, it is bigger than Pluto. Pluto is often considered the king of the

Kuiper belt, the biggest object that we know of that formed there, until we consider that Triton once ruled that area before Neptune captured it. So, although Triton is a moon of Neptune, it could be said that it is the biggest and most massive Kuiper Belt object. Further evidence for this was found as New Horizons passed Pluto in 2015, suggesting Triton and Pluto share a near identical composition, which supports the theory that they share a common origin. Beyond Triton are six other irregular moons. found much further out. They are almost certainly captured objects too, with unusually eccentric orbits that take years to complete. They were probably perturbed into these weird orbits by the gravity

of Triton. So, if Triton was a captured object, how did that happen? Objects need to lose momentum to be captured, otherwise they would have enough momentum to escape. Well, we can't know for sure, but the leading theory right now is that Triton was once part of a binary system, perhaps like Pluto and Keron. As Neptune approached Triton and its moon, the gravity from the encounter would have caused the binary system to fall apart, with Triton's moon being slingshot away, and Triton losing enough momentum to be captured in orbit around Neptune. I mentioned that Triton shares similar characteristics with Pluto. What exactly does that entail? Well, they both have a predominantly nitrogen ice surface with other ice mixed

in, like water and carbon dioxide. It has quite a flat terrain, its topography never varies by more than a kilometre, although Voyager 2 did see ridges and troughs, plateaus and ice plains. What you may find unusual though is that it has very little in the way of craters. This implies its surface is very young and is constantly being renewed. Like Pluto, it also has some reddish patches, which is thought to be methane having reacted to UV light from the sun, producing what is known as tholins, an organic compound that has a supposedly tar-like consistency. While organic compounds do not mean life is present there, organic compounds are the basic chemicals from which life forms. Life likely couldn't exist on the surface of trite,

anyway, as it's far too cold and the sun far too dim to support any life form that we can imagine. But what's interesting is what could be found under Triton's crust. Under Triton's surface is thought to be a rocky and metallic interior, which gives Triton a reasonably high density for a moon at 2 grams per centimeter cubed. Because of this, and also due to the big step-up in size from the next biggest moon in the solar system, Titania, it has more mass than all the moons smaller than it in the whole solar system combined. The radioactive decay from the rocky core could be enough to heat and power convection in a subsurface ocean of water, much like what is thought to be under the surfaces of Europa, Enceladus,

and some other large moons in the solar system. And just like Europa and Enceladus, cryovolcanism is an active process today on Triton. Liquid water in the mantle erupts onto the surface like lava on earth. This is the main reason why the surface is so young. It has been actively renewed by liquid water erupting and then freezing on Triton surface. Some very young lava planes have been identified, sparse and flat regions, yet interestingly with a wall that surrounds the plane. This is called a planitia, or in other words, a solidified lava lake. We also can see Caldra, which is the collapse. found at the centre of a cryovolcano where lava planes formed from.

It is thought that the water from these eruptions would have also brought minerals from the underground oceans onto the surface, perhaps even being the source of the tholins and organic matter I mentioned earlier. If this is the case, and organic compounds are found in the subsurface ocean, it means that there's a possibility that conditions are right for life to have been able to form there. We also see long lines permeating over the surface. These are likely faults caused either by tectonic activity or freeze-thor weathering processes. If we look at some more of the Voyager 2 images of Triton, we can see the results of some recent eruptions.

You'll notice what looks to be dark deposits on the surface, in cone or funnel-like shapes up to 150 kilometers long. However, these smaller eruptions may not originate from the mantle itself. Voyager 2 spotted some plumes reaching 8 km high, but these are thought to be because of a solid greenhouse effect within the moon's icy crust. Imagine the surface of Triton, consisting of a clear ice, which is settled on dark deposits like tholins. The sun shines through the ice, warming the darker, more absorbent tholins beneath,

sublimates a pocket of ice under the surface. As the ice is sublimate, the pressure builds in the air pocket until the surface above the pocket gives way, causing an eruption. This eruption also takes the dark deposits with it, spreading them out over the surface again. If this is the case, a very similar process has been seen on Mars's poles, with carbon dioxide ices and darker deposits under the ice layer. This process can only exist because of one thing, Triton has an atmosphere, although not as thick as scientists were initially expecting. Triton's atmosphere is thin, only 0.014 millibars, about the equivalent of 80 kilometers up on Earth, although like Pluto, this density varies through seasonal changes.

Since Voyager 2's observations, Triton's atmosphere has become denser, as the surface has warmed, evaporating a little of the nitrogen ices on the surface. However, when Voyager 2 passed, Triton's atmosphere was still dense enough to support weather up to 8 kilometers above its surface. In this image, you can actually see clouds on Triton. And going back to the image of the plumes, you can see the deposits from the eruptions all end up facing the same direction, due to a prevailing wind in that region of the moon. Like Pluto, Triton's atmosphere is hazy, the cause of which is thought to be hydrocarbons in the atmosphere, not yet broken down into tholins by UV light from the sun.

The constant depositing of organic compounds through cryovulcanism, ice is evaporating and freezing again through seasonal variations, and a weather-rich, active atmosphere makes Triton a very dynamic world. All of these factors combined make it one exceptionally unusual moon. It is more a dwarf planet than a moon. But what about the others? 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 Samatha 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. One of the major discoveries Hubble made about Neptune was the discovery of a new moon in 2013, which has now been named Hippocamp.

Now, Hubble has discovered many moons in its time, especially around Jupiter and Saturn, but what makes Hippocamp special is that it could well be a fragment from the much larger moon of Neptune, Proteus. The 400km wide moon does indeed look like it had a tumultuous past, with giant impact craters 50 to 100 kilometers in diameter. One of these collisions likely fragmented parts of Proteus, which then fell into orbit around Neptune. Hippocamp is probably the biggest fragment, as it's an irregular 35 kilometres long object and orbits fairly closely to the larger proteus.

Finally, there is one last object that shares a strange relationship with Neptune, not quite a moon, but certainly something that it captured and influenced by its gravity. 2020 VN40 is a trans-Nptunean object that orbits the Sun exactly once for every 10 orbits Neptune completes. For point of reference, that means it has an orbital time around the Sun of 1,650 years, while Neptune orbits every 165 years. 2020 VN40's orbital plane is highly inclined, but its precise 10 to 1 ratio showcases that it is in, something known as an orbital resonance with Neptune, captured in a delicate gravitational dance with the larger planet.

This finding helps showcase the far-reaching influence Neptune has on the wider solar system. So there you have it. Neptune is a fascinating world that plays an important role in the gravitational tug of war at the extreme edges of our solar system. Along with Uranus, it's the planet we know that. least about, as we have only visited it once and glimpsed it with telescopes infrequently. There's still so much for us to learn about its weather, its internal structure, and its moons. Sadly, there are no confirmed missions planned to return to this Azure world, and given NASA's

looming financial difficulties, none are on the horizon. On the other hand, China is considering a proposal for a Neptunean probe that could be launched could be launched as soon as 2033. If it goes ahead, who knows what discoveries will be uncovered. I hope we do see a new mission go ahead. Neptune has so much more story to tell, and although it is extremely difficult to access, sometimes the best things in life are the ones that seem just out of reach. And for us, there is no planet in our solar system harder to explore than this, the final

planet, Neptune. If you've ever watched an astrum video and wish that you could dive deeper into some of the wonders of the universe, or simply wish you could stare at some of the images for longer, then you need a copy of our book. With stunning imagery and thoughtful explanations that are accessible to all, this first book takes you on a trip through the solar system that you really don't want to miss. And who wouldn't want to have their mind filled with the spectacular wonders of space? Join your fellow space lovers.

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