Navsphere after exploding active spacecraft

1. Launch spacecraft
2. in space select a part of the spacecraft
3. from the popup menu explode the selected item

Assuming the craft is entirely destroyed then you should be left with just a navsphere. Although in Map mode you should still be near Earth, the navsphere will continue to travel in the direction of the spacecraft you just exploded, but with no gravitational effect it will continue through space in a straight line.