Airdate: Dec 02, 2008
Scientist: Seth Shostak
KSC SETI - Broadcasting
Talking with E.T. is truly a long-distance call.
music; ambience instant messaging chimes
In this age of emails and instant messaging, you can get in touch with anyone anywhere in no time at all, but try sending an interstellar message and youâ€™re in for a long wait. Iâ€™m Jim Metzner, and this is the Pulse of the Planet.
â€œOne of the problems we have, if you really wanna communicate with ET, if heâ€™s really out there and listening to our broadcasts, is that theyâ€™re so far away, well, youâ€™ve gotta have a lot of patience for conversation.â€
Alpha Centauri is the closest star system to our own solar system, and if you want to send a radio message there at the speed of light, the expected delivery time would be almost four and a half years. And thatâ€™s why Seth Shostak and other scientists at the SETI Institute concentrate their energies not on sending messages, but on listening for them.
â€œImagine. You go on the air. You speak into the microphone, â€œHello, Alpha Centauri.â€ Four and a half years later that signal gets there. Now, if thereâ€™s somebody there to answer, then they speak into their microphone, and they give you a reply, and it takes another four and a half years for that to get back to us. So, nine years have gone by between when you said, Hello,â€™ and when they reply, Umm, didnâ€™t quite get that. Could you repeat it?â€™â€
Just because the SETI Institute doesnâ€™t transmit messages into outer space doesnâ€™t mean that weâ€™re not represented up there. Television shows, radar signals, even radio programs like this one can emanate into space and travel through the cosmos at the speed of light.
â€œWhen they send those signals out from those big antennas on the hills, unavoidably some of those signals just leak right off the Earth and go out into space. Weâ€™ve had television for maybe 60 years? That means theyâ€™ve washed over a few thousand stars already.â€
Hello Alpha Centauri! If you know of a third to sixth grader who wants to learn more about the search for life in outer space, have them check out kidsciencechallenge.com.
Pulse of the Planet is made possible by the National Science Foundation. Iâ€™m Jim Metzner.