By extension, any object in this kind of orbit has also become known as a Trojan, so Mars, Uranus and Neptune all have Trojans of their own. Earth's first Trojan, the asteroid 2010 TK, was identified in 2011. Saturn's moons Tethys and Dione, meanwhile, share their own orbits with Trojan satellites.
Let me understand the last sentence(Saturn's moons Tethys...).
In this context, what the Trojan satellites is?