and maintained. Each surface is maintained
to within a centimeter (0.4 inches). That’s like
grooming the surface of a soccer field to vary no
more than the height of a single LEGO brick.
Goldstone, Madrid and Canberra also
have several 34-meter (111-foot) diameter
antennas. These use two technologies, a highefficiency antenna and beam waveguide
antenna. Each site also has a 26-meter (85feet) diameter antenna primarily used today
to track spacecraft a bit closer to home, in
Earth orbit only 100 and 620 miles (160 and
1,000 km) away. These smaller dishes were built
to communicate with Apollo astronauts.
The images of the Apollo 11 landing watched live by over 500 million
people worldwide were received through the Canberra complex.
Credit: NASA HQ/Bob Jacobs/Mark Hess
History
DSN dates back to the founding of NASA
itself. In 1958, the Jet Propulsion Laboratory
positioned portable tracking stations in
Nigeria, Singapore and California to track
Explorer 1, the first successful U.S. Satellite.
The network expanded in 1967 to support Apollo
missions with the Honeysuckle Creek Tracking
Station near Canberra. The iconic TV images of
Neil Armstrong’s “Giant Leap” were received
through that antenna before retransmission via
Intelsat to a dish to the Jamesburg Earth Station
near Monterey, California. The slow scan format
used by the cameras on the moon was converted
to a standard broadcast format and again
transmitted to Houston and then on to a half billion
televisions around the world. Live video from Apollo
missions was also received through antennae at
Goldstone. The engineers involved were recognized
for their technical innovations in 2009 with the
Philo T. Farnsworth Primetime Emmy Award.
The DSN’s capabilities to receive extremely
weak signals helped bring the astronauts
aboard Apollo 13 home safely when a ruptured
oxygen tank crippled their capsule. Every bit
of power was needed by spacecraft systems
during re-entry leaving little for the transmitters.
Engineers were able to maintain contact with
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