I am hoping to find axial tilts for asteroids and also their spring and fall equinox. Some of the asteroids I'm interested in are: 4 Vesta, 1 Ceres, 24 Themis, 65 Cybele, 153 Hilda, 624 Hektor
What causes an asteroid to loose control over it's orbit and enter in to another objects atmosphere?
I was watching the TED lecture How to defend Earth from asteroids , and the speaker Phil Plait spoke of the possibility of this asteroid hitting Earth. Is this really a concern?