Being a fan of the Navy's Precision Flight Team - the Blue
Angels - I have always marveled at their wing tip to wing tip
flying. In reading NASA's recent news release about Ebb and Flow
(GRAIL A & B) flying formation around the Moon at 3,600 mph, I
was amazed - I mean AMAZED (!) at the tolerances that the two
spacecraft are capable of. Here is what NASA says as to the
twins' flying ability: "How slight a distance change can be
measured by the science instrument beaming invisible microwaves
back and forth between Ebb and Flow? How about one-tenth of one
micron? Another way to put it is that the GRAIL twins can detect
a change in their position down to one half of a human hair
(0.000004 inches, or 0.00001 centimeters). For those of you who
are hematologists or vampires (we are not judging here), any
change in separation between the two twins greater than one half
of a red corpuscle will be duly noted aboard the spacecraft's
memory chips for later downlinking to Earth. Working together,
Ebb and Flow will make th