{HEAD ~ The method} 13, wherein {TAIL ~ the first system} is a first spacecraft and the second system is a second spacecraft 
wherein
{ HEAD ~ The method } 13 , wherein { TAIL ~ the first system } is a first spacecraft and the second system is a second spacecraft
HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH