A field of radio dishes that look like giant dinner plates have waited for years in the mountains of Northern California for the first call from intelligent life among the stars.
But they are not listening any more because cash-strapped governments, it seems, can no longer pay the interstellar phone bill.
Astronomers at the SETI Institute said a steep drop in state and government funds has forced the shutdown of the Allen Telescope Array, a powerful tool in the search for extraterrestrial intelligence, an effort scientists refer to as SETI.
The 42 radio dishes had scanned deep space since 2007 for signals from alien civilisations while also conducting research into the structure and origin of the universe.
The shutdown came just as researchers were preparing to point the radio dishes at a batch of new planets.
About 50 or 60 of those planets appear to be about the right distance from stars to have temperatures that could make them habitable, says Seth Shostak, senior astronomer at the institute.
"There's plenty of cosmic real estate that looks promising," he said. "We've lost the instrument that's best for zeroing in on these better targets."
SETI Institute chief executive Tom Pierson said in an email to donors last week that the University of California, Berkeley, had run out of money for day-to-day operation of the dishes. "Unfortunately, today's government budgetary environment is very difficult, and new solutions must be found," Mr Pierson wrote.
The 50 million-dollar (£30 million) array was built by SETI and UC Berkeley with the help of a £18 million donation from Microsoft co-founder Paul Allen. Operating the dishes cost about £909,000 a year, mostly to pay for the staff of eight to 10 researchers and technicians to operate the facility. An additional £606,000 a year was needed to collect and sift the data from the dishes.
The Paul G Allen Family Foundation, the billionaire's philanthropic venture, had no immediate plans to provide more funding, said David Postman, a foundation spokesman.