This week the news from SciShow Space is gonna be all about moons. 

First a major update from one of our favorite moons in the entire solar system; Europa. Sometime in the 2020s, NASA wants to send an orbiter, called Clipper, to Jupiter's 4th largest moon. And last week, the space agency announced what scientific instruments will be along for the ride.

Out of 33 proposals, 9 different detectors made the final cut and they'll be working together toward answering the same question: What the frick is going on out there?

As you probably know, all signs point to a huge ocean sitting below Europa's icy surface. And the Hubble Space Telescope has even detected hints that the ocean might be spurting up plumes of water vapor. An ocean is a healthy environment for evolving organisms, naturally, and the plumes suggest that there's an active exchange of chemical compounds going on between the ocean and the atmosphere. So these 9 instruments are designed to explore that whole dynamic in at least 3 different ways. 

One of the more basic ways to investigate another world is just to figure out what it looks like and why? So the Europa imaging system will take photos of the moon's surface, getting resolutions so high that in some areas as little as half a meter will be represented by a pixel.

To learn more about the moon's composition, NASA also selected two types of spectrometers for the mission. The MISE instrument will identify substances found on the surface of the moon while the MASPEX will look at those in the atmosphere. Together these instruments should give us a clear picture of what Europa's subsurface, surface, and thin atmosphere are made of.

Then there will be 3 more tools that will focus mostly on the ocean. An instrument called REASON will use radar to map the structure of the icy crust plus the ocean below. Meanwhile, PIMS and ICEMAG will use Europa's magnetic field to study the properties of the ocean like how far below the surface it is and how much salt there is in it.

The final group of tools will analyze the vapor plumes if they exist, which we're not even sure about yet. 

So the Europa Thermal Emission Imaging System will search for those plumes using heat because those jets of vapor would be warmer than their surroundings. The Ultraviolet Spectrograph, on the other hand, will be combing Europa's atmosphere for the wavelength of ultraviolet light that corresponds with the presence of water molecules. Finally the Surface Dust Mass Analyzer will identify particle within the plumes.

With the data from these 9 instruments, the hope is that we'll gain a better understanding of the conditions that we think are the prerequisites for life and whether they exist on Europa. Plus the European Space Agency is sending its own orbiter to Jupiter's moons including Europa around the same time so expect to hear a lot about that icy moon in the near future.

Shifting over to a moon of Saturn, this week the Cassini Probe made its very last fly-by of the moon Hyperion. With a diameter of 270 km, Hyperion is Saturn's 7th largest moon. And it happens to looks weirdly spongy. Its density is so low, that impacts from meteorites actually compress the moon in places, giving it that spongy-looking texture.

And for the first time, we got to see the other side of Hyperion up close. At 34,000 km out, this wasn't the closest we've ever come to Hyperion. Back in 2005, Cassini swept past the moon from only 505 km away. But the thing about Hyperion is that its orbit is really irregular thanks to the gravitational influence of Titan so in all of our fly-bys, we've only had a chance to see one side of it. But on Sunday we finally buzzed the moon in just the right way to get the pictures of the other half.

Even though, this was Cassini's last visit to Hyperion, it still has a few more scheduled encounters with other moons. On June 16, the probe will do a fly-by of Dione, a dense moon with a diameter of over a 1000 km, which it will pass by again in August.  And we'll also get 3 more fly-bys of both Enceladus and Titan this year, so there are many more portraits of these world headed our way in the months to come.

If you wanna keep up with what's going on in the universe, then continue watching SciShow Space News, which was brought to you by our patrons on Patreon. If you wanna help make this show possible, you can go on patreon.com/scishow and see the cool stuff you can get. And don't forget to go to youtube.com/scishowspace and subscribe.