If there's something you'd like to say to aliens, now's your chance. The Wow! signal, a mysterious radio transmission detected in 1977 that may or may not have come from extraterrestrials, is finally getting a response from humanity. Anyone can contribute his or her two cents or 140 characters, to be exact to the cosmic reply via Twitter.

All tweets composed between 8 p.m. EDT Friday (June 29) and 3 a.m. EDT Saturday (June 30) tagged with the hashtag #ChasingUFOs will be rolled into a single message, according to the National Geographic Channel, which is timing the Twitter event to coincide with the premiere of the channel's new series, "Chasing UFOs."

Then on Aug. 15, exactly 35 years after the Wow! signal was detected, humanity's crowdsourced message will be beamed into space in the direction from which the perplexing signal originated.

"We are working with Arecibo Observatory to develop the best way to encrypt the transmission," said Kristin Montalbano, a spokeswoman for the National Geographic Channel.