STAR TREK LIVE! - Ontario Science Centre

Teachers Resource Manual
Experiment: Space Radio
Explanation
Energy in the electromagnetic spectrum travels in
waves. The wavelengths define the type of
electromagnetic radiation. The electromagnetic
spectrum includes white light, infrared, ultraviolet
light, gamma rays, X-rays, microwaves, and radio
waves (see image) . White light is part of the
visible electromagnetic spectrum. Ultraviolet light,
gamma rays, and X-rays have wavelengths too
small for us to see, but they can affect us. UV light
can give us sunburns. Infrared, microwaves, and
radio waves are also part of this spectrum. Their
wavelengths are too long for us to notice.
Radio waves can be longer than a football field or
as short as a football. Radio waves carry signals to
radios, televisions, and cellular phones. A radio
station’s numbers reflect its radio wave frequency
(number of waves that cycle per second). AM
radio waves are longer than FM radio waves. You
know this when you look at a radio station
numbers: a 690 AM news station compared to a
99.1 FM rock station. AM waves are much longer.
This means they can be filtered out by larger holes
than FM waves, just like pouring marbles and sand
through a sieve.
Courtesy of NASA/JPL-Caltech
Astronauts use radio waves to communicate with
their coworkers on Earth and in space. Many
astronomical objects also emit radio waves.
Scientists built radio telescopes to capture the
emissions and translate them into images. Star Trek
takes radio signals one step further. The Enterprise
captain would tell the communication officer to
open hailing frequencies to communicate with
other galactic vessels. Hailing frequencies
encompass all the possible radio waves that
another civilization may use for
telecommunication. Saying “open frequencies”
means the captain wishes to establish contact such
as knocking on somebody’s door.
Space Radio
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