When talking about the age of the universe we’re talking about the age of everything in it. But how can we possibly talk about the age of the universe if everything in it has its own personal time? If you have some stars swirling about in a galaxy, then you can be pretty sure that they’re moving well below the escape velocity. The escape velocity from the surface of the Earth is 11km/s, which yields a gamma of . The escape velocity from the core of a large galaxy (such as ours) is on the order of a thousand km/s.