Thanks for your great question! In fact, it’s such a good question that scientists are asking the exact same thing. As you may know, Jupiter is a giant planet that is mostly made up of helium and hydrogen gases. Scientists are not completely sure if Jupiter has a solid core. Most scientists think that the center of Jupiter is made of something called liquid metallic hydrogen. Hydrogen is normally a colorless gas, but because the pressure is so high in Jupiter’s center the hydrogen changes and becomes a fluid, like water. It also has some properties similar to metal and reflects light like a mirror. Although scientists are fairly sure that there is liquid metallic hydrogen in the center of Jupiter, they are not sure if there are heavier elements that form a solid core right in the middle. Some scientists think there is solid rock in the very center, while others think that the center is more like a very thick soup of liquid metal.

I’m sorry I can’t give you a more definite answer, but that’s because scientists are still trying to figure out the answer! Right now, there is a spacecraft called Juno that is on its way to Jupiter! It left Earth four years ago and is expected to get to Jupiter on July 4th next year (2016). The spacecraft will circle around Jupiter and collect information from the atmosphere and the magnetic field around the planet. Perhaps what we learn from Juno will help us answer your question? Be sure to check out the NASA website next summer and maybe scientists will have a better idea of what Jupiter’s core is like.