Turns out, there’s a lot more floating around the planet Saturn than those famous rings. Space scientists announced last week they’ve discovered Saturn has 128 more moons, for a total of 274, far more than its larger neighbor Jupiter, with just 95 moons.

University of Iowa physics and astronomy professor Allison Jaynes says she’s betting Saturn has still more moons that we haven’t spotted yet.

“I think there are more. This is one of the cases of — the closer you look, the more you see, which is often the case in science,” Jaynes says. “We just didn’t notice these smaller moons, because they’re very hard to track, and they’re very hard to prove that they’re orbiting Saturn, which is one of the conditions upon which we’ll designate an object a moon.” 

The closest the Earth ever comes to Saturn is about 746-million miles, so it’s giant leap to even pick out a few of its moons from this distance, let alone tracking 274 separate moons in orbit.

“It’s a huge logistical problem, which is why we haven’t noted them before,” Jaynes says. “The way that this was done was using a telescope to take very precise measurements of extremely faint objects, these tiny fragments that are now considered moons around Saturn, and track them over time to prove that they have an orbital period that is centered around the planet Saturn.”

Why does Earth only have one moon and Saturn has nearly 300? First of all, Saturn is nine times wider than Earth, meaning, if Earth were the size of a nickel, Saturn would be about as big as a volleyball, so it’s gravitational pull is much stronger.

“We are very small, and we’re also farther in towards the Sun, where there isn’t a lot of debris, and hasn’t been a lot of debris,” Jaynes says. “If you think about the asteroid belt, that’s out closer to Jupiter, and so there is a question about why doesn’t Jupiter actually attract more moons than it has?”

So where did all of these moons around Saturn come from? One popular theory, Jaynes says, it that they were created by the collisions of objects that were already captured by Saturn’s gravity well.

“So, unstable objects that smashed into each other became clouds of debris and then continued to orbit Saturn,” Jaynes says. “But again, we need more information, and we don’t really know for sure. We’ve only had a few spacecraft actually fly to Saturn to discover and look at things up close.”

Much of what we know about Saturn came from a NASA probe called Cassini, which spent 20 years in deep space. Some of Cassini’s instruments were built at the University of Iowa, including one that measured radioactive emissions and waves in the ionized gas, called plasma, which surrounds the ringed planet. Its fuel nearly spent, Cassini was intentionally sent to burn up in Saturn’s atmosphere in 2017.