The asteroid Pallas.

Pallas, minor-planet designation 2 Pallas, is the second asteroid to have been discovered (after Ceres), and one of the largest in the Solar System. It is estimated to comprise 7% of the mass of the asteroid belt and its diameter of 544 kilometres (338 mi) is slightly larger than that of 4 Vesta. It is however 10–30% less massive than Vesta, placing it third among the asteroids. It is possibly the largest irregularly shaped body in the Solar System (that is, the largest body not rounded under its own gravity), and a remnant protoplanet.


With 1.84% of Earth's Gravity, it would not be very useful/healthy for us to live on, even if given radiation shielding, a dome-enclosed atmosphere, water cycles, etc. So we might actually end up hollowing it out, spinning it on its axis fast enought to produce 1 G of centrifugal force, and inhabitants would live on the inner walls of the asteroid. The rock layers would provide protection from micrometeorites and cosmic radiation, while sunlight on the inside can be reflected into the inside through the two entrances at each pole. Basically, Pallas could be an alternate form of the O' Neil Cylinder known as an "asteroid terrarium ".