The researchers turned their telescopes to the heart of the galaxy, in the hope that if civilizations tried to communicate, they would choose an obvious focal point.
In cities, these gathering places are called Schelling points; in London, for example, Buckingham Palace and the "Big Ben" clock tower of Westminster Palace. Scientists believe that galactic centers could serve as Schelling points for civilizations that cannot communicate with each other.
They believe that an advanced civilization may have placed a powerful intergalactic transmitter in the heart of the galaxy, perhaps fueled by the supermassive black hole in the heart of the Milky Way.
"The galactic center is the subject of a very specific and concerted campaign with all of our facilities," said Dr. Andrew Siemion of the University of California, the principal investigator.
"If you and I have arranged to meet in New York on a particular day, but we haven't decided on a particular time or place, we could both choose noon at Empire State Building or the Statue of Liberty, "he said at a meeting of the American Association for the Advancement of Science (AAAS) in Seattle.
"If an advanced civilization, somewhere in the Milky Way, wanted to put a beacon somewhere ... the galactic center would be a good place to do it."
Breakthrough Listen, based at the Berkeley SETI (Alien Intelligence Research) University Center, is supported by a 100 million dollar (£ 77 million) grant from Russian billionaire Yuri Milner.
The team released nearly two petabytes, or a million gigabytes, of data yesterday, and the public was encouraged to browse it.
"For the whole of human history, we had a limited amount of data to search for life beyond Earth. So we could only speculate, "said Milner. "Now, as we get a lot of data, we can do real science - and by making this data available to the general public, anyone who wants to know the answer to this deep question can do it." "
The project uses telescopes around the world to listen to radio signals.
Although many scientists believe that the first "aliens" to be found will be tiny bacterial species living below the surface of Mars, or in the frozen oceans of moons like Titan, which orbits Saturn, Dr. Siemion thinks that the "techno -signatures "will be our first clue to life outside of Earth. "There are two horses in the race to find life beyond Earth," he said.
"The first is the search for chemical signatures of the planets and the second is the search for extraterrestrial intelligence. Smart life has an advantage because it can detect technologies like ours across the galaxy and ... beyond ours.
"The search for simple life forms is limited to our solar system and a few nearby stars, and we can never be sure that the methane or similar chemicals we detect are actually produced by living things.
“It comes down to the statistics. Basic life can be very common, but we are much less likely to find it. When asked if he believed that intelligent extraterrestrial life existed, he replied, "Absolutely, yes. The project also looked for planetary systems that could see Earth. Scientists spot exoplanets - those outside the solar system - by looking for an obscuring witness in a star as a world orbits it.
The telescopes were aimed at an area of the galaxy where an advanced alien race could use the same technique to see the Earth pass through the Sun.
"Are there other civilizations that search for extrasolar planets themselves? Could they have discovered the Earth by watching the Earth pass in front of our Sun? Asked Dr. Siemion.
"Maybe they ... have learned that it harbors a technologically capable being.
“We call this region of the sky the land transit zone. And the field of study has long suggested that this particular type of sky, where other stars could see the Earth crossing the Sun, would be a very interesting place to do SETI research. "