Apollo Expeditions to the Moon
THE LM ON ITS OWN
The fifth day of the Apollo 9 mission was the crucial test
for the LM. Schweickart and McDivitt entered the LM, powered it
up, and prepared to separate from the command module. They
released the craft, and the astronauts were flying free in the
LM. They backed away and rotated the module so that Scott, in the
command module, could see that all the legs were down and
extended, and that there were no physical failures in the craft
itself. Then they fired the descent engine just enough to move
the LM into a parallel orbit about three miles away from the
command module. The mechanics of the orbit were such that the LM
was on its own, but twice during each swing around the Earth? the
two spacecraft were close enough so that Scott could initiate
rescue operations should anything have happened to the EM.
For nearly six hours the two astronauts in the LM rehearsed
the possible phases of the lunar approach and departure. They
exercised the reaction control systems, fired the descent engine
again, then jettisoned the descent stage, and then fired the
ascent engine for the first time in space. From their adjusted
position about 10 miles below and 80 miles behind the command
module, they began their approach to a rendezvous and docking,
much the same as the actual event to take place later on Apollo
11. The first phase of their rendezvous terminated temporarily
with about a 100 foot separation, so that both spacecraft could be
photographed. Then they docked, a solid and clean joining that
verified the crews' training and the performance of the docking
and locking mechanisms. They jettisoned the ascent stage, and
remotely fired its engine to insert it into a highly elliptical
orbit around the Earth.
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The rendezvous radar antenna on the LM, untried in space,
was photographed through a CM window by one of the
Apollo 9 crew, perhaps in anticipation of the fact that it
would soon be unstowed, powered up, and put to the all-important test.
A critical and sophisticated part of the rendezvous system,
it worked beautifully when tried two days roter.
The curved metal strap at the extreme left, not part of the
antenna, is a handrail to be grasped by an Astronaut floating
outside the spacecraft.
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From here on, the rest of the mission was almost an
anticlimax, because the performance of the spacecraft left no
doubt as to its ability to make the lunar trip, complete with
landing and departure. But there was still work to be done, and
so for the remaining five days in orbit, the crew again and again
exercised the service propulsion system, once to lower the
perigee of their Earth orbit, once to test the propellant staging
system, and once to head home to Earth. On the last four days,
they also did a series of landmark tracking experiments, using
visual sightings of Earth features which were observed and
photographed. They also made a number of photographs with a
multiple-camera assembly using different film emulsions to obtain
pictures in different portions of the photographic spectrum.
These were further augmented by pictures taken almost
simultaneously with hand-held cameras, using conventional films.
Once out of orbit, following the eighth successive firing of
the service propulsion system, the reentry was normal. They
landed right on their target in the Atlantic, 241 hours after
takeoff, and were recovered quickly by Navy helicopters.
Apollo 10 was different, because it did go to the Moon- or
at least within 47,000 feet of it- in its rehearsal of the Apollo
11 mission. There had been some speculation about whether or not
the crew might have landed, having gotten so close. They might
have wanted to, but it was impossible for that lunar module to
land. It was an early design that was too heavy for a lunar
landing, or, to be more precise, too heavy to be able to complete
the ascent back to the command module. It was a test module, for
the dress rehearsal only, and that was the way it was used.
Besides, the discipline on the Apollo program was such that no
crew would have made such a decision on its own in any event.
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In the cheerful mood prevailing
when the three crew members
were back together, Dave Scott
mugs for Rusty Schweickart's
camera. Here he shows how he,
when alone in the command
module, had had to peer against
the glare to catch his first
glimpse of the LM as it flew back
in rendezvous.
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Five hard days of carefully
doing what had never been done
before shows in the strained
face of Apollo 9 Commander
Jim McDivitt, normally a relaxed
and equable man. Attempting to
describe the cool courage of McDivitt
and Schweickart when they
went off for the first time over
the horizon in the unlandabie LM,
some observers declared it the
bravest act since man first ate a
raw oyster.
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Thomas P. Stafford was the Apollo 10 mission commander, with
command module pilot John W. Young and lunar module pilot Eugene
A. Cernan. They were launched on schedule at 11:49 AM, on May
18, 1969, about two and one-half months after Apollo 9 had set
out on its successful test flight.
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