The Search for Extraterrestrial Intelligence (SETI) at University of California, Berkeley, announced on Thursday that it had detected radio signals which looked similar to "what we think might be produced from an extraterrestrial technology".
The revelation prompted a flurry of claims by online science magazines and bloggers that SETI scientists were working to decipher the "alien" signals.
Tweets including "SETI announced possible #Alien#Signal" and "SETI might have found alien signals" appeared, while other users wondered: "If we get #SETI trending worldwide, will the aliens respond?"
But it appears the truth was not out there, after all. The blog by the SETI team was hastily updated the following day to clarify that the weird signal was interference which had originated from our own world.
It read: "We know these signals are interference, but look similar to what we think might be produced from an extraterrestrial technology."
The update was also accompanied by a statement which said: "It became clear that we had not stated as definitively and absolutely as possible that these signals are interference. We have update(d) the post to make this clear. Sorry for any confusion."
The project to search for signs of intelligence on habitable planets uses the Green Bank Telescope in West Virginia – the world's largest fully steerable radio telescope – which targets planets outside our solar system which have been detected by Kepler, a space telescope launched by NASA in 2009.
Last December much excitement was triggered by the news that the telescope had found a new planet outside the Earth's solar system that is eerily similar to our own world.
Scientists said Kepler 22-b has temperatures of about 22ºC and may have continents and oceans like the Earth which could support life. But the downside is that it is 600 light years from our own world.
More than 80 possible candidate planets which could have liquid existing on their surface have been chosen for the search being led by the Berkeley SETI team.
They are trying to detect any radio signals which could be sent from extraterrestrial intelligence by "listening in" to signals from the telescope while it is being used for other experiments. The project also involves about one million volunteers who are participating by running a free programme on their home computers that can analyse radio telescope data.
Although the scientists concluded that their first findings are examples of radio frequency interference of the terrestrial kind, they noted that picking up signals with "similar characteristics to what we expect from ET" is a good indication that the first steps of their detection methods are working properly.
And those hoping for signs of life in outer space will be pleased to hear that the Berkeley SETI team will soon be posting results of the analysis when they receive more data.
The situation so far was summed up by one disappointed tweeter: "SETI picked up a signal ... but it's not aliens.