Stasis
Stasis happens when a player ship's shields are reduced to below 0. In order to prevent the destruction of the ship, the ship goes into stasis right before hull breach. Stasis fields are deadly to life forms, though, so you are ejected from your ship in an escape pod if you have one right before the stasis field activates. If you don't have an equipped escape pod, then you die and enter spirit form and are ejected as a spirit.
The ship first goes into heavy stasis, which appears blue and stays there for as long as it takes for the Shields to recharge or 5 minutes (whichever is shorter). The ship then enters light-stasis, which appears yellow, where the owner of the ship can re-enter it by flying his or her Pod or Spirit over the ship.
If you fail to reclaim your ship once it goes into light stasis after a certain amount of time, then it leaves stasis and you can no longer reclaim it normally and any player or AI that wants to can easily blow it up. Because of this, it is advised to never leave your ships in light stasis for too long. The amount of time a ship stays in light stasis before leaving is equal to 24 hours plus 12 hours per tech level of the hull.
Slave ships which have a Stasis Generator equipped also enter into stasis when they run out of shields. Once they reach light-stasis, they may be reactivated by selecting them, hitting 'x', and choosing Leave Stasis from the menu.