Do you believe in aliens? If you do, do they really exist? If you have a chance to cantact with aliens, what would you say to them?
The Wow! Signal
In 1977, a mysterious radio transmission was detected at the Big Ear radio observatory in Ohio, coming from the direction of the constellation Sagittarius. At its peak, the 72-second transmission was 30 times more powerful than ambient radiation from deep space, prompting the volunteer astronomer Jerry Ehman to scrawl “Wow!” next to the data on a computer printout, giving the signal its name.
No one knows whether the seemingly unnatural signal really was beamed toward us by aliens, and despite great effort, scientists have never managed to detect a repeat transmission from the same spot in the sky. Thirty-five years on, the Wow! signal remains a complete mystery.
And if they’re the aliens that sent the Wow! signal in the first place, they are likely to be an extremely advanced civilization. Scientists say the signal would have required a 2.2 gigawatt transmitter, vastly more powerful than any existing terrestrial radio station.
On Aug. 15, exactly 35 years after the Wow! signal was detected, scientist with National Geographic Channels will beamed humanity’s crowdsourced message into space in the direction from which the perplexing signal originated, as the reply for the signal.
How advanced could they possibly be?
If aliens do exist, however, we still can measure the advanced of their civilization by their energy consumption, as theoretical physicist Michio Kaku has written about that on his article The Physics of Extraterrestrial Civilizations.