2001 February 19
Why would the shadow of a
space shuttle
launch plume point toward the Moon?
Two weeks ago during the launch of
Atlantis, the
Sun,
Earth,
Moon,
and rocket were all properly aligned for
this photogenic coincidence.
First, for the
space shuttle's plume to cast a long shadow,
the time of day must be either near
sunrise or
sunset.
Next, just at sunset, the
shadow
is the longest and extends all the way to the
horizon.
Finally, during a
Full Moon, the
Sun and
Moon are on
opposite sides of the sky.
Just after
sunset, for example,
the Sun is slightly below the
horizon, and,
in the other direction,
the Moon is slightly above the
horizon.
Therefore, as
Atlantis blasted off, just after
sunset,
its shadow projected away from the Sun
toward the opposite horizon, where the
Full Moon just happened to be.