An asteroid with a diameter of 500km has an impact strength of 4000J/kg. What is the largest sized crater diameter which can be formed without melting the asteroid? The asteroid has a density of 3.5 g/cm^3 and the impact velocity is 5km/sec I have a few formulas: The asteroid will not melt if: kinetic energy < mass* impact strength and, crater diameter is proportional to W^(1/3) I have no information about the body being impacted so I don't know if I can use the formula for crater diameter as it requires information about the material strength of the body being impacted for an accurate answer. I approximated the asteroid as a sphere (as I was given a diameter) and calculated the mass and the kinetic energy which I got to be : 2.875*10^27 Joules. However, the mass* impact strength is four orders of magnitude less. I guess I'm not entirely sure how to approach this problem. Any suggestions?