You are piloting a spaceship through outer space and see an asteroid with a smooth enough surface to allow a landing. You decide to do some calculations before landing the spaceship on this asteroid. What would be the best angle of descent for the spaceship to ensure it suffers minimal or no damage? Please assume that the velocity of the spaceship when orbiting the asteroid is $1000$ m$/$s and the gravitational acceleration at a height less than $100$ km from the surface of the asteroid is $0\mathrm{.}5$ m$/$s$2($and assume it is $0$ at the height of more than $100$ km$)$