Get the message
Each spacecraft is equipped with one or more antennas to transmit and receive signals. Information is stored in digital form as a string of 1s and 0s and sent through space in the form of radio waves.
These travel at the speed of light, but the signals have a long way to travel back to Earth. Signals from the Cassini spacecraft orbiting Saturn take about an hour to reach our planet.
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Cassini's main antenna is the big white dish at the top of the spacecraft
Image: NASA / JPL |
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