An ambitious new SETI (search for extraterrestrial intelligence) test is underway.

At 3 p.m. EDT (1600 GMT) today (May 24), Europe’s Trace Gas Orbiter Mars probe beamed a coded message toward Earth. Sixteen minutes later, it was received by three big radio telescopes on Earth, kicking off a global effort to decipher the cryptic signal.

That effort is A Sign in Space, a multiweek project led by Daniela de Paulis, the current artist in residence at the SETI Institute in Mountain View, California and the Green Bank Observatory in West Virginia.

“Throughout history, humanity has searched for meaning in powerful and transformative phenomena,” de Paulis said in a statement.

“Receiving a message from an extraterrestrial civilization would be a profoundly transformational experience for all humankind,” she added. “A Sign in Space offers the unprecedented opportunity to tangibly rehearse and prepare for this scenario through global collaboration, fostering an open-ended search for meaning across all cultures and disciplines.”

The Green Bank Observatory is one of the three scopes that listened for the Trace Gas Orbiter’s signal today, along with the SETI Institute’s Allen Telescope Array in northern California and the Medicina Radio Astronomical Station in northern Italy, which is managed by the Italian National Institute for Astrophysics.

source space.com