Most Active Stories Sun September 25, 2011 Launch Logistics:
Speedy Rocket, Slow Electronics Weird things jump out at me in
press releases. Take the press kit NASA prepared for the GRAIL
mission. GRAIL consists of two nearly identical spacecraft that
are on their way to the moon. Once there, they will make a
precise map of the moon's gravitational field. Such a map will
help scientists refine their theories about how the moon formed
and what the interior is made of. So I'm reading through the
GRAIL press kit, learning about the size of the spacecraft
(washing machine-sized), how long it will take to make the map
(approximately three months), and where the mission control room
is (at a Lockheed Martin facility just outside of Denver). I
also learn that GRAIL can launch any day between Sept. 9 and
Oct. 19. And then I get to this sentence: "On each day, there
are two separate, instantaneous launch opportunities separated
in time by approximately 39 minutes." That's weird. Now, I
wasn't surprised that this missio