@S1-A.ARPA,@MIT-MC.ARPA:jennings@AEROSPACE.ARPA (09/18/85)
From: Richard K. Jennings <jennings@aerospace.arpa> Re Steve Benz's proposal to lock onto color to determine relative velocity, Two problems: Radial velocity is only one component of relative velocity -- it is not clear how angular velocity can be measure via colors; As the radial velocity approached the speed of light, the measurement instrument would have to become (in the limit) infinitely precise. -- Rich.