Orbit of the International Space Station

G = Quantity[1, "GravitationalConstant"];

rE = UnitConvert[PlanetData["Earth", "Radius"], "SI"]

mE = UnitConvert[PlanetData["Earth", "Mass"], "SI"]

h = Quantity[400, "Kilometers"]  (* Average height of orbit above surface *);

r = rE + h

v = UnitConvert[Sqrt[G  mE / r], "SIBase"]

{period = 2 π r / v, UnitConvert[period, "Minutes"]}

The acceleration due to gravity is not very different from that on Earth’s surface.

g = UnitConvert[G mE / (r^2), "SIBase"]

Energy

mISS = Quantity[4.196 * (10^5), "Kilograms"];

KE = UnitConvert[(1/2) mISS v^2, "Joules"]

PE = UnitConvert[- G mE mISS / r, "Joules"]

KE/PE