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A NASA satellite has just observed an asteroid that is on a collision course with the Earth. The asteroid has an estimated mass, based on its size, of 4.85×10^9 kg. It is approaching the Earth on a head-on course with a velocity of 593 m/s relative to the Earth and is now 4.85×10^6 km away. With what speed will it hit the Earth's surface, neglecting friction with the atmosphere?

I found g using (mass of earth)(mass of sat)/(r^2)

of course since x = 4.85×10^6 km = 4.85×10^9 m

so g=

(5.98e24)/(4.85e9) <--since one of the r's cancels out with the mass of sat

then i used v^2 = vo^2 + 2ax

using g as a and everything else is pretty explanitory.

Where'd I go wrong?

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# Can someone check my work?

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