The galilean moons orbit the planet

If you have ever played an Elder Scrolls game and observed the night sky, you'd notice that there are two moons (most notable in Oblivion and Skyrim). They both orbit Nirn, the planet the game is based in. At a closer inspection, it is revealed that the smaller moon revolves around the large moon. Which brings me to my question: Would it be possible for there to be one large moon with two small moons in close proximity to each other orbiting said large moon that orbits the planet? Or, would there be catastrophic outcomes like erupting volcanoes or tsunamis? Let's say the planet is Earth but is a 1/3 the size, and the largest moon is a 1/3 the size of Earth's moon and then smaller still (because I've read Earth's moon is abnormally large). The simple answer is yes, it is possible for a planet to have three moons. Many planets in the Sol system have more than three moons. Jupiter has 69 known moons, for example. Neptune has 14. Of the rocky planets, Mars has two moons, and depending on your specific definition of moon, Pluto has as many as I can't speak to whether or not two smaller moons could be orbiting a larger moon. A system like that is theoretically possible, but probably highly unlikely to occur naturally. With multiple moons, consider setting up some kind of orbital resonance. A good example of this are three of Jupiter's Galilean moons: As long as your moons aren't too large compared to your planet, their tidal forces aren't going to cause catastrophe. $\begingroup...

NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute 67 moons orbit the great gas giant Jupiter; of these, the four largest are known as the Galilean moons, having been discovered by Galileo Galilei using his telescope in 1610. The four moons are Io, Europa, Ganymede, and Callisto, in order of distance from Jupiter. (Their names derive from lovers of Zeus.) These moons provided evidence that not all celestial bodies orbit the Earth, a powerful revelation as, up until that time, astronomers considered Earth the center of the universe. [See Space.com is the premier source of space exploration, innovation and astronomy news, chronicling (and celebrating) humanity's ongoing expansion across the final frontier. Originally founded in 1999, Space.com is, and always has been, the passion of writers and editors who are space fans and also trained journalists. Our current news team consists of Editor-in-Chief Tariq Malik; Editor Hanneke Weitering, Senior Space Writer Mike Wall; Senior Writer Meghan Bartels; Senior Writer Chelsea Gohd, Senior Writer Tereza Pultarova and Staff Writer Alexander Cox, focusing on e-commerce. Senior Producer Steve Spaleta oversees our space videos, with Diana Whitcroft as our Social Media Editor.

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