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