Scientists at the Search for Extra-terrestrial Intelligence (SETI) Institute use 42 giant radio dishes in northern California to look for distant transmissions, but their quest for extra-terrestrial life was threatened after a lack of funding jeopardised the programme.
The Allen Telescope Array project, named after its first financial backer, Microsoft co-founder Paul Allen, managed to raise donations that went beyond the $200,000 initial fund-raising goal.
After funding from the institute's partner, the University of California Berkeley was partly cut in April the dishes used, which are also known as the Allen Telescope Array, were mothballed.
The project however proved to be popular and enjoyed wide public support, leading up to 2,000 people contributing to help the programme stay open.
Celebrities have now mobilised and a web site called the SETIStar website, have launched an online appeal.
Among them is Hollywood star Jodie Foster, who played a character inspired by SETI co-founder Dr Jill Tarter in the science fiction film "Contact" and wrote in a note to the SEI: "In Carl Sagan's book/movie Contact a radio signal from a distant star system ends humanity's cosmic isolation and changes our world.
"In Carl Sagan's book/movie Contact, a radio signal from a distant star system ends humanity's cosmic isolation and changes our world," she said.
"The Allen Telescope Array could turn science fiction into science fact, but only if it is actively searching the skies. I support the effort to bring the array out of hibernation."
Another SETIStar is Larry Niven, the science fiction writer who wrote books such as the multi award-winning Ringworld, The Magic Goes Away and The Draco Tavern.
"Finding intelligent tool users would reset all parameters. All of human history would look like a preface," he said on the SETIStars website.
Another well-known contributors is astronaut Bill Anders who flew around the moon on Apollo 8 in 1968 and said: "It is absolutely irresponsible of the human race not to be searching for evidence of extra-terrestrial intelligence."
Following such support from the public, Tom Pierson, chief executive officer of SETI, announced the search would resume in September: "We are so grateful to our donors. You never know when or if a signal is going to be detected, so if you miss a few months, how important is that? It's impossible to know. Being off-air is something we needed to fix."
SETI costs $1.5 million (£930,000) a year to run and the institute is now in talks with the US Air Force as it tries to establish more permanent funding, The telegraph reports.