Q&A: General Astronomy and Space Science

Q:
If sound and images from early radio and television left Earth, would it be possible to pick up the signals in the distant outer space of the Universe?

A:
Our radio and television broadcasts do travel out from Earth into space. For approximately 100 years, since the very first radio broadcast on Earth, we've been sending out electromagnetic waves with information about ourselves. Since radio waves are simply a long wavelength of electromagnetic waves, they travel at the speed of light. So, if there were a detector within 100 light years of Earth, it could receive these signals.

A good article about sending and receiving signals from intelligent life may be found on one of NASA's websites:
http://ksnn.larc.nasa.gov/pokemon/deoxys/et.shtml

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