Q&A: General Astronomy and Space Science
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?
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: