If any intelligent aliens out there are attempting to send us a message, they are likely to die out before their signals reach us.
That’s the conclusion of scientists in Switzerland who say the delay in picking up radio signals means we’re destined to never meet ET.
Their study is based on the assumption that distant civilization will use radio signals to transmit messages, which travel at around 186,000 miles, per second.
While this may sound fast, in cosmic terms, it is extremely slow.
Our galaxy alone spans 100,000 light years across. Although humans have been sending radio waves for 80 years, they will have only travelled a maximum of 0.001 per cent of the galaxy in that time.
Making contact is particularly unlikely when you consider that any civilisation is unlikely to be able to survive for more than 100,000 years, researchers say.
‘If the civilisation emitted from the other side of the galaxy, when the signal arrives here, the civilisation will already be gone,’ Dr Claudio Grimaldi, the lead researcher from the École Polytechnique Fédérale de Lausanne told Science News.
The study, currently available on the pre-publication site arXiv, looks at the Drake equation, first coined by astrophysicist and astronomer Frank Drake in 1961.
Taking into account seven variables, this is model that estimates the number of planets in our galaxy that could be home to alien life.
It takes into account factors like the rate of star formation, the amount of stars that could form planetary systems, the number potentially habitable planets in those systems.
‘We develop a simple model of the galaxy that includes both the birthrate and detectable lifetime of civilisations to compute the possibility of a SETI detection at the Earth’, researchers wrote in the unpublished paper.
‘The transmissions arriving at Earth may come from distant civilisations long extinct, while civilisations still alive are sending signals yet to arrive’.
Researchers at SETI (Search for Extraterrestrial Intelligence Institute) are currently working on a world-wide network of specialised cameras, allowing scientists to detect alien signals shorter than a millisecond.
In 2016, Professor Cox said we’re unlikely to discover an alien civilisation in any case.
This is because civilisations inevitably self-destruct.
According to The Sunday Times, Professor Cox’s suggestion is that the rate of advances in science and engineering in any type of alien civilisation may outstrip the development of political institutions able to manage them.
So technology that allows the generation of power but produces greenhouse gases, or nuclear weapons, may destroy civilisations within a few thousand years of being developed, which could threaten ours too.
The problem was first posed by physicist Enrico Fermi in 1950 who claimed any life form with rocket technology could colonise the galaxy in a few million years, so why wasn’t there any evidence already?
Professor Cox said: ‘One solution to the Fermi paradox is that it is not possible to run a world that has the power to destroy itself and that needs global collaborative solutions to prevent that.
‘It may be that the growth of science and engineering inevitably outstrips the development of political expertise, leading to disaster.’