Aliens might have been attempting to contact us for DECADES, scientists declare – as they warn we have been ‘on the lookout for the incorrect factor’

For decades, we’ve been looking to the skies for any sign of aliens – but it turns out we may have been missing attempts at contact.

A new study has cast doubt on our radio signal detection methods, arguing that ‘space weather’ could be distorting incoming transmissions.

Until now, most experiments have focused on identifying spikes in radio frequency – signals unlikely to be produced by any other natural processes in space.

But experts have highlighted an overlooked complication.

Even if an extraterrestrial transmitter produces a perfectly narrow radio signal, it may not remain narrow by the time it leaves its home star’s atmosphere.

This distortion, which happens near the point of origin, can ‘smear’ the signal’s frequency, meaning it can be missed by our detectors that are primed to search for more focused radio waves.

‘Searches are often optimized for extremely narrow signals,’ Dr Vishal Gajjar, astronomer at the SETI Institute and lead author of the paper, said.

‘If a signal gets broadened by its own star’s environment, it can slip below our detection thresholds, even if it’s there, potentially helping explain some of the radio silence we’ve seen in technosignature searches.’

For their study, the team analysed radio transmissions from our own spacecraft in the solar system.

Using measurements from probes, they worked out how turbulent plasma released from stars – such as the Sun – affects radio signals.

This data was then used to determine what might happen in a wide range of space environments.

They explained that M–dwarf stars, which constitute about 75 per cent of stars in the Milky Way, have the highest likelihood of distorting signals.

The discovery could lead to better detection methods that take this into account.

It means even when signals are not ‘perfectly razor–thin’ by the time they reach Earth, they could still come from extraterrestrial life.

‘By quantifying how stellar activity can reshape narrowband signals, we can design searches that are better matched to what actually arrives at Earth, not just what might be transmitted,’ Grayce C. Brown, co–author of the study, said.

Writing in The Astrophysical Journal, the researchers concluded: ‘The so–called Great Silence, when extended to the radio technosignature searchers, is not solely evidence for the absence of transmitters, but also a reflection of our detection limitations arising from a mismatch between the assumed signal morphology and the broadened line shapes.

‘Recasting non–detections with width–aware pipelines will clarify how much of the Great Silence reflects a true absence of transmitters versus selection effects.’

Looking ahead, the researchers argue that astronomers should bear their findings in mind to ensure that technosignatures ‘are not systematically missed’.

Scientists generally believe that the best candidates for alien life are ‘Earth–like’ worlds orbiting distant stars in other parts of the galaxy.

One such contender is the Earth–sized planet TRAPPIST–1e, located just 40 light–years from Earth, which is located safely within its star’s habitable ‘Goldilocks zone’.

Another promising candidate is the planet K2–18b, which some studies suggest could be teeming with life.

Last week, a NASA veteran claimed that aliens do exist – they just haven’t visited Earth yet.

Dr Gentry Lee has worked at the US space agency since 1968, when he first got involved with the Viking mission to Mars.

He has since spent more than half a century designing probes to land on distant planets – but argues Earth has not yet been visited by other–worldly beings.

‘There exists nothing today that says any alien or any alien machine has ever landed on the planet Earth,’ he told the American Association for the Advancement of Science (AAAS) conference in Phoenix. ‘If you believe otherwise, you are being misled.’

According to the expert, in every case of a supposed UFO sighting or alien encounter, there is likely a simpler explanation for those phenomena.

But when it comes to distant planets, life has ‘just got to be there somewhere’.

He added: ‘We are going to find life of some kind somewhere else. The odds are overwhelming.’

In 1977, an astronomer looking for alien life in the night sky above Ohio spotted a radio signal so powerful that he excitedly wrote ‘Wow!’ next to his data.

The 72–second blast, spotted by Dr Jerry Ehman through a radio telescope, came from Sagittarius but matched no known celestial object.

Conspiracy theorists have since claimed that the ‘Wow! signal’, which was 30 times stronger than background radiation, was a message from intelligent extraterrestrials.