Image Source: Bigear.org.
It's been just over 33 years since we received the only message from space that ever seemed to constitute an intelligent transmission: 6EQUJ5. This message was picked up by the Big Ear radio telescope at about 11:16 p.m. Eastern Daylight Savings Time on August 15, 1977 at Ohio State University Radio Observatory. There is a history of the transmission here. Dr. Jerry R. Ehman, who was part of the SETI project working at the Observatory, noted the transmission and made the famous margin note: "Wow!" There is an explanation of the values 6EQUJ5 here (different numbers and letters measured intensities of power in the transmission).
Close-up of the computer print-out. Image Source: Bigear.org.
According to SETI, this message came from the constellation Sagittarius, with the closest star to the transmission being Terebellum (Omega).
Location of the source of transmission. Image Source: SETI.
From this origin point, the message was actually 200 years old by the time it reached us; and an answer from us would take another 200 years to reach the source in the Omega Sagittarii system. That means that the senders would have to wait almost half a millennium to receive an answer to their original message from Earth.
Recording of the Wow! signal. Video Source: Youtube.
Caption from the video: "The Wow! signal was a strong, narrowband radio signal detected by Dr. Jerry R. Ehman on August 15, 1977 while working on a SETI project at the Big Ear radio telescope of Ohio State University. The signal bore expected hallmarks of potential non-terrestrial and non-solar system origin. It lasted for 72 seconds, the full duration Big Ear observed it, but has not been detected again. It has been the focus of attention in the mainstream media when talking about SETI results. Amazed at how closely the signal matched the expected signature of an interstellar signal in the antenna used, Ehman circled the signal on the computer printout and wrote the comment "Wow!" on its side. This comment became the name of the signal."
This year, Stephen Hawking mentioned this signal in his Discovery Channel series, Into the Universe. In his first installment in this series, he discusses the possibility of alien life, what they might be made of, what aliens might be like. He speaks of the chemical components of life: I didn't know that there were 45 pounds of carbon in the average adult man. Nor did I know that carbon could conceivably exchanged with silicon as a building block for life (see part 3/5 of the episode below for the recipe that makes up a human being). He also speculates that aliens might be made of sentient gas. The Wow! signal is mentioned in the 4th Youtube segment of this episode, posted below.
Into the Universe, 1/5. Video Source: Youtube.
Into the Universe, 2/5. Video Source: Youtube.
Into the Universe, 3/5. Video Source: Youtube.
Into the Universe, 4/5. Video Source: Youtube.
Into the Universe, 5/5. Video Source: Youtube.
Hawking feels that communicating with aliens is risky. He thinks that the key to space exploration and human-alien contact will ultimately result from anti-ageing research: "We only have to look at ourselves to see how intelligent life might develop into something we wouldn't want to meet. We humans are already capable of manipulating the course of our own evolution. Exactly the same, presumably, would be true of advanced extra-terrestrials. Ultimately, they could halt ageing and become virtually immortal. What's more, they might have reached that point millions of years ago. It might sound unlikely, but if you think about it logically, alien technology should be as extraordinary to us as a rocket ship to a caveman."