Riddle of the radio waves in outer space
Unexplained signal seems to come from nearby star
A MYSTERIOUS radio signal from a nearby star has excited a team of alien-hunting astronomers.
Researchers believe the waves are coming from the area around Proxima Centauri, the closest star to Earth except the sun.
A narrow beam was spotted by the Parkes radio telescope in Australia in spring this year and, unlike previous radio bursts, it has not been attributed to any natural or human-created source, such as a passing satellite.
The team, f rom the Breakthrough Listen Project – a £70million initiative to find alien life – said it is one of the most exciting discoveries in decades.
It has been compared to the ‘WOW! signal’ of 1977, picked up by the Big Ear Radio Observatory, in Ohio. That gained its name after astronomer Jerry Ehman wrote ‘Wow!’ next to the data.
‘[This] is the first serious candidate since the “Wow! signal”,’ an astronomer told The Guardian.
The beam appears to originate from near Proxima Centauri. It is 4.2 light years from Earth with two confirmed planets, a Jupiter-like gas giant and the rocky Proxima b.
Proxima b is an Earth-like world in the star’s ‘ habitable zone, an area where liquid water could flow on the surface of the planet, scientists believe.
However, as Proxima Centauri is a red dwarf, the smallest and coolest kind of star, the habitable zone is very close to the star.
This means it is probably tidally locked like the moon, with half of the planet in constant daylight, and the other in everlasting darkness. It is also therefore probably exposed to intense radiation, so civilisation is unlikely – at least on the surface.
Lewis Dartnell, an astrobiologist from the University of Westminster, said: ‘It’s hard to imagine how you can have a stable climatic system and all the things you need to get from bacteria, which are hardy, up to intelligent animal life forms, which certainly are not. But I’d love to be proved wrong.’
The signal was detected in the 980MHz range, and shifts in the frequency are consistent with the movement of a planet. This suggests it could be evidence of a third planet within the system.
David Rothery, professor of planetary geosciences at the Open University, said it was very unlikely that someone was sending a signal.
He added: ‘It would be a very freakish coincidence if aliens on the nearest exoplanet to us just happened to have developed radio technology at around the same time, given we got it only about 120 years ago.’
‘A freakish coincidence’