By Tyler DeWacht
Good day to you, and welcome back to Space News! In the last edition, we focused on the outer edges of our Solar System. This time, the focus shall lay upon the gas giants. There isn’t much going on with Uranus and Neptune at the moment nor will there be in the foreseeable future, so my focus here will be on Jupiter and Saturn. Let’s blast through it, shall we?
Jupiter has many moons, but just how many are there? More and more moons keep getting discovered, and the current count now sits at 79 moons. Why does Jupiter have so many moons? One of the newest moons discovered, Valetudo, may answer this question. Most of the moons are orbiting in sync with Jupiter’s clockwise rotation. Not Valutedo though, Valutedo is moving counterclockwise, akin to driving down the wrong side of a highway. If moons moving in opposite directions were to collide like this, some would shatter into more moons, explaining why these multitudes of mini-moons exist.
We haven’t found life on Mars just yet, but what about the larger moons of Jupiter? Can they support life? That’s what the Jupiter Icy Moons Explorer (aka JUICE) mission intends to find out in 2029. Ganymede, Callisto, and Europa are all thought to have enough water to potentially support life, and the European Space Agency is set to launch a mission to further explore these frigid moons in 2022. Io isn’t habitable and as such is not a viable candidate, but it is a hotspot for volcanic activity with at least 150 volcanoes confirmed and as many as 250 more thought to exist. If we ever find a way to efficiently harness volcanic energy, Io would be a great potential source of power.
The moons are an interesting topic in and of themselves, but what about Jupiter itself? The Juno probe has given us a look at many of the features and atmospheric components on the turbulent topside of this great gas giant. For instance, we’ve learned that deep within the Great Red Spot is a cloud layer likely composed of frozen water. Good luck trying to harvest it though, you’d be better off just sticking to the moons. It’s also given us our first look at the poles of Jupiter. Jupiter’s North Pole, oddly enough, looks like pepperoni pizza. The South Pole, meanwhile, is oddly blue and has a lot of mini storms, bearing little resemblance to the Jupiter we know.
I say South Pole, but should I really say South Poles? The more we learn about Jupiter, the stranger it becomes. Jupiter’s magnetic field doesn’t seem to act the way we’re familiar with; it appears to have two South Poles, and we’re not really sure why. Perhaps it has something to do with the planet’s core, but we need more data before any further conclusions can be drawn on the matter. Luckily, the Juno spacecraft’s mission has been extended until July 2021, so it will have more time to explore this conundrum.
You’ve probably heard of the Great Red Spot, but what about the brown barges? Approaching roughly the size of 140,000 barges, Hurricane Gaston is nothing compared to these superstorms. They often don’t last too long and are difficult to spot, but they’re nothing to be scoffed at either. If they pick up enough momentum, one could become the next Great Red Spot in the future. The spot we know has been around since the 1600s, but it’s been losing so much speed lately that Jupiter will likely lose this iconic mark in less than 20 years. No storm lasts forever, after all.
Moving over to the ringed beauty Saturn, did you know it gets an aurora borealis? You probably won’t be able to see it; it’s mainly made from ultraviolet light due to the high concentration of hydrogen in the atmosphere. Hubble managed to capture the elusive aurora before, but the space telescope captured the clearest images yet as Saturn recently went through its summer solstice. Fun fact, Saturn also has a strange jet stream at the North Pole in the shape of a hexagon. Crazy how nature does that, isn’t it?
We know all this because of the Cassini space probe, which took a death plunge into Saturn’s atmosphere on September 15. It did that intentionally so as not to accidentally post-mortem contaminate any of the other moons with Earth bacteria. Enceladus in particular is a prime moon candidate for alien life, as is evidenced by the global subglacial ocean and the complex organic molecules recently discovered erupting from a jet.
The largest Saturnian moon, Titan, is also a curious case. The largest known methane lake, Kraken Mare, rivals the Caspian Sea; many other dot the surface as well, as the Cassini probe was able to capture in one final image before it took the plunge. In addition to having a nitrogen-based atmosphere like Earth, Titan also appears to have dust storms. At surface temperatures of -180°C, it couldn’t support advanced life, but the planet is still fascinating to research nonetheless.
As previously mentioned, there isn’t much news for the farthest gas giants. However, if you’re into stargazing, the planet Uranus will reach its opposition point with Earth on October 24. Neptune also recently passed the opposition point on September 7. It’s a good time if you want to get a good look at either planet through a telescope. In the case of Uranus, you may even be able to see it with just binoculars.
That’s all the current news in space for the gas giants. In the next edition, we set our sights much closer to home. Until then, keep gazing at the stars and planets!