On November 16, 1974 the Arecibo radio telescope sent a coded message toward the globular cluster M13, 25,000 light-years away.  The message was 1,679 bits of data and was a pattern that an alien civilization is supposed to decode.  The message contains crude images of numbers 1 to 10, a stick-figure of a man, chemical formulas, including the code for DNA, a sketch of the Solar System, and an image of the radio telescope.  If we received a message like that from the stars, could you decode it?  Let's find out -- here's the challenge:

It's late at night.  You're monitoring shortwave signals on 2380 MHz and you suddenly get some slight frequency shifts.  You decide to hit the record button on your data scope, and the message completes in less than 3 minutes. Now what?  Have you received a real message from an alien civilization or is it just a hoax?  You better be right before you call a press conference! You don't need a deep understanding of mathematics, science or cryptology to solve "The Three Trees Riddle" -- it's just for fun, and you'll know if you're right..

The message you have received.