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After 35 Years, Another Message Sent From Arecibo
0xdeadbeef writes "Two weeks ago, MIT artist-in-residence Joe Davis used the Arecibo radio telescope to send a message to three stars in honor of the 35th anniversary of the famous Drake-Sagan transmission to M13 in 1974. It was apparently allowed but not endorsed by the director of the facility, and used a jury-rigged signal source on what will now be known as the 'coolest iPhone in the world.' The message encoded a DNA sequence, but no word yet on whether it disabled any alien shields. You can get the low-down on Centauri Dreams: Part 1, Part 2."
The idea that we can send radio signals to alien civilizations, or receive them, is unfortunately wishful thinking. "Contact" notwithstanding, it's not possible. We could never pick up a radio signal from an alien civilization because the power of a signal from a point source drops off exponentially. And it's not a matter of having a better amplifier either, because radio waves are actually quantized....eventually your signal has degraded to individual photons, and it doesn't take very long. My friend and I calculated that even with a MW-level transmitter, an alien civilazation on Alpha Centauri would need an impractically large dish to intercept even a trickle of photons.