[OT] physics help

I'm trying to figure the escape velocity for Alarish.  Diameter = 5103km
(.4
Earth), mass is 2.08E+23kg (.034795 Earth), density = 3g/cm^3  . 
Applying
the formula in Gillett's Worldbuilding, p12 (the simplified form,
k*r*sqrt
rho), I get .208 km/sec  ... however, comparing it to Ganymede, Io, etc,
I
suspect it ought to be more like .3km/sec.  Help?

--Chris  DeBoe laserlight@cwix.com
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