In STARSTRUCK, at one point Rigel impresses Marsha with a telescope that can easily see Leda, a very small moon of Jupiter. Rigel is in turn impressed that Marsha knows so much about this obscure celestial body, to include that it wasn’t discovered until 1974. Rigel’s little telescope in his house somehow provides a view of Leda far beyond the capacity of any telescope on Earth.Leda really does exist and it really is a Moon of Jupiter that was discovered in 1974. Jupiter has a whopping 67 confirmed Moons! Some are quite large. Ganymede, for example, is larger than the planet Mercury! However, many others are very small, to include tiny Leda.
According to Wikipedia, STARSTRUCK provides the first cultural reference to Leda by name. You can find more about Leda here.