Odd signal from a galaxy far, far away
Sam Jones
Thursday September 2, 2004
The Guardian
Had it happened once, it would have been interesting. Twice would have been a bit of a coincidence. But scientists believe a strange radio signal from space spotted three times last year could be a message from another world.
The signal has only been observed for about a minute in total, not long enough to allow astronomers to analyse closely.
But it is unlikely to be the result of any radio interference or noise, and does not resemble an astronomical object.
Some say the signal could have been produced by a previously unknown astronomical phenomenon, or a glitch in the Arecibo radio telescope in Puerto Rico that picked it up.
Those involved in the Search for Extra-Terrestrial Intelligence (Seti) think otherwise.
The signal is the most exciting find in the six-year history of the Setihome project, which uses programmes running as screensavers on millions of personal computers worldwide to sift through the vast amount of data from Arecibo.
"It's the most interesting signal from Setihome," said radio astronomer Dan Werthaimer from the University of California at Berkeley. "We are not jumping up and down, but we are continuing to observe it."
The signal, which has been honoured with the decidedly unexotic name SHGbo2+14a, has a frequency of about 1420MHz, says New Scientist, one of the main frequencies at which hydrogen, the most common element in the universe, absorbs and emits energy.
Some scientists say aliens trying to introduce themselves would be likely to transmit at this frequency.
The signal appears to be coming from between the constellations Pisces and Aries, where there is no obvious star or planetary system within 1,000 light years.
Eric Korpela, another University of California researcher, said: "We are looking for something that screams out 'artificial'. This just doesn't do that, but it could be because it is distant."
The signal has a rapidly fluctuating frequency, which could occur if it was beamed out from a rapidly spinning planet or object, although a planet would have to be rotating nearly 40 times faster than Earth to produce the same drift. A drifting signal would be expected to have a different frequency each time it was detected.
Yet with every observation of SHGbo2+14a, the signal has started off with a frequency of 1420MHz before starting to drift - although this could be connected to the telescope.
Another possibility is that someone could be hacking into the software. But Mr Korpela says he cannot think of any way to fake such a signal.