Okay kiddo, so you know how everything is made of tiny particles called atoms? Well, there are some atoms that are really special because they have a lot of energy and they're all squished together really tightly. When you squish them together like that, they start to act like they're one big atom instead of a bunch of little ones.
Scientists call this big atom a fermi ball. It's like a tiny, super-dense ball of energy. It's so dense that even light can't escape from it! These fermi balls can be found in things like neutron stars, which are really, really, REALLY heavy stars that have collapsed in on themselves.
Fermi balls are really fascinating to scientists because they behave in ways that we don't fully understand yet. They might even help us learn more about the mysteries of the universe! Pretty cool, huh?