Scientists believe Jupiter's moon Europa has an ocean underneath its icy shell. Today, we'll get a closer look at one of the instruments on NASA's Europa Clipper that could tell us more about this hidden ocean. This is Hi-V2 at NASA's Jet Propulsion Laboratory, where work is being done on Europa Clippers magnetometer. A magnetometer is a device that measures the strength of the magnetic field. A magnetic field is created by flowing electrical currents in objects or in fixed magnets. In the case of Europa, it's an electrical current that's flowing in Europa that generates a magnetic field that we can detect with these sensors. The magnetometer will confirm the existence of the oceans, but it also provides more detailed information than that. It'll also tell us about how much salt there is in the ocean, and also may provide information about how deep the ocean is under the ice. The size of the magnetometer, it's about a foot and a half diameter canister, and it is about 28 feet long. The sensors themselves are very small, and they're located at the three different plates halfway down the boom, three quarters of the way down, and right at the tip of the boom. We put the sensors far enough away that the spacecraft doesn't interfere with the readings. The reason we're doing this test is to make sure that when we let go of it in space, it's going to pop back to the shape it's supposed to be in. The importance of doing that today is to make sure that all the systems are operating as expected as a last check before we actually mount the Meg Boom to the spacecraft and launch the spacecraft on the rocket. The reason that we do this test in a different high bay than the spacecraft is that as you can see, this 28 foot long beam is very large. So once we complete all of our testing in this room, we're going to transport it to the room next door, and over there we're going to do some electrical testing with all the spacecraft electronics and harnessing before it gets bolted to the spacecraft. So what we're looking at here is called a hempholks coil system. We're going to be using this to cancel out Earth's magnetic field, and that gives us a good opportunity to really see the capability of our sensors. Every single component that comes close to our sensor has to be screened, belt buckles, clothes, glasses, all of these things carry a magnetic charge. If they've reached a certain distance from our sensor, they can damage it. So we're really excited to build this magnetometer to be able to really verify that an ocean might exist. Stay tuned as we keep you updated on all the developments happening in the next few months as the mission prepares for the scheduled launch of Europa Clipper in 2024.