or through planetary rings or gravitational fields. Radio
Science Receivers record these changes for study
• Very Long Baseline Interferometer: Two or more DSN
stations working together to create a giant antenna to
observe spacecraft
or astronomical
objects such as
quasars. Here
on Earth VLBI
can measure
continental drift.
Transmitters on each spacecraft produce around 20
watts but the long trip across the solar system reduces
that to one billionth of one billionth of a watt. DSN
regularly hears from Voyager 2 over 9.7 billion miles from
Earth. It takes over
14.5 hours for signals
to make it to and
from this spacecraft.
Signals delivered
by the dish to ultrasensitive receiving
systems capable of
Each complex
communicating with
is equipped with a
spacecraft more than
September 3 was like any other day at the DSN. A wide variety of NASA and other
70 m diameter (230
spacecraft communicate via multiple antennae at each of the three complexes.
16 billion kilometers (10
foot) parabolic dish
billion miles) from Earth.
antenna, weighing
To achieve th H