# Why does Titan have an atmosphere while similar moons such as the Galilean moons don't?

The Galilean moons of Jupiter are similar in size to Titan and are also protected by their parent planet's magnetic field. How come only Titan is able to maintain an atmosphere?

• temporary -1 for zero supporting links. Where does this information come from? How do you know? How can readers know that it is correct? Without supporting links or references it's impossible to judge the quality of the answer or the validity of the statements. Please add a few supporting links, thanks! – uhoh Aug 20 at 13:06