The Dish on ET
Astronomers are banking on a promising new technology to trace extra-terrestrials in the same way that one locates a needle in a haystack.
The Allen Telescope Array (ATA) comprises hundreds of small dishes that combine modern, miniaturised electronics and innovative technologies with computer processing.
It endows researchers with the capability to search for possible signals from advanced civilisations elsewhere in our galaxy – if they are transmitting in this direction.
Employing this new equipment in a unique, targeted search for possible civilisations enhances the chances of finding one, said Richard Conn Henry of Johns Hopkins University.
Researchers will particularly target the ecliptic, a great circle around the sky that represents the plane of Earth’s orbit. The sun, as viewed from Earth, appears annually to pass along this circle.
Any civilisation that lies within a fraction of a degree of the ecliptic could annually detect Earth passing in front of the Sun. This ecliptic band comprises only about three percent of the sky.
“If those civilisations are out there – and we don’t know that they are – those that inhabit star systems that lie close to the plane of the Earth’s orbit around the sun will be the most motivated to send communications signals toward Earth,” Henry said.
Through spectroscopic analysis of our atmosphere, they will know that Earth likely bears life.
“Knowing where to look tremendously reduces the amount of radio telescope time we will need to conduct the search,” he said.
Most of the 100 billion stars in our Milky Way galaxy are located in the galactic plane, forming another great circle around the sky.
Ray Villard of the Space Telescope Science Institute, who will join the team in its observations, said: “It occurred to me that alien civilisations along the ecliptic would likely be doing similar observations to Earth.”
This quest will be a collaborative effort among Richard Conn Henry of Johns Hopkins University, Seth Shostak of SETI Institute and Steven Kilston of Henry Foundation Inc. St/jg