Don’t talk to aliens, warns Stephen Hawking
He's right. If there are ET's out there, we better hope they never find us.
Hawking has depicted what kinds of alien could be out there
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THE aliens are out there and Earth had better watch out, at least according to Stephen Hawking. He has suggested that extraterrestrials are almost certain to exist — but that instead of seeking them out, humanity should be doing all it that can to avoid any contact.
The suggestions come in a new documentary series in which Hawking, one of the world’s leading scientists, will set out his latest thinking on some of the universe’s greatest mysteries.
Alien life, he will suggest, is almost certain to exist in many other parts of the universe: not just in planets, but perhaps in the centre of stars or even floating in interplanetary space.
Hawking’s logic on aliens is, for him, unusually simple. The universe, he points out, has 100 billion galaxies, each containing hundreds of millions of stars. In such a big place, Earth is unlikely to be the only planet where life has evolved.
“To my mathematical brain, the numbers alone make thinking about aliens perfectly rational,” he said. “The real challenge is to work out what aliens might actually be like.”
The answer, he suggests, is that most of it will be the equivalent of microbes or simple animals — the sort of life that has dominated Earth for most of its history.
One scene in his documentary for the Discovery Channel shows herds of two-legged herbivores browsing on an alien cliff-face where they are picked off by flying, yellow lizard-like predators. Another shows glowing fluorescent aquatic animals forming vast shoals in the oceans thought to underlie the thick ice coating Europa, one of the moons of Jupiter.
Such scenes are speculative, but Hawking uses them to lead on to a serious point: that a few life forms could be intelligent and pose a threat. Hawking believes that contact with such a species could be devastating for humanity.
He suggests that aliens might simply raid Earth for its resources and then move on: “We only have to look at ourselves to see how intelligent life might develop into something we wouldn’t want to meet. I imagine they might exist in massive ships, having used up all the resources from their home planet. Such advanced aliens would perhaps become nomads, looking to conquer and colonise whatever planets they can reach.”
He concludes that trying to make contact with alien races is “a little too risky”. He said: “If aliens ever visit us, I think the outcome would be much as when Christopher Columbus first landed in America, which didn’t turn out very well for the Native Americans.”
The completion of the documentary marks a triumph for Hawking, now 68, who is paralysed by motor neurone disease and has very limited powers of communication. The project took him and his producers three years, during which he insisted on rewriting large chunks of the script and checking the filming.
John Smithson, executive producer for Discovery, said: “He wanted to make a programme that was entertaining for a general audience as well as scientific and that’s a tough job, given the complexity of the ideas involved.”
Hawking has suggested the possibility of alien life before but his views have been clarified by a series of scientific breakthroughs, such as the discovery, since 1995, of more than 450 planets orbiting distant stars, showing that planets are a common phenomenon.
So far, all the new planets found have been far larger than Earth, but only because the telescopes used to detect them are not sensitive enough to detect Earth-sized bodies at such distances.
Another breakthrough is the discovery that life on Earth has proven able to colonise its most extreme environments. If life can survive and evolve there, scientists reason, then perhaps nowhere is out of bounds.
Hawking’s belief in aliens places him in good scientific company. In his recent Wonders of the Solar System BBC series, Professor Brian Cox backed the idea, too, suggesting Mars, Europa and Titan, a moon of Saturn, as likely places to look.
Similarly, Lord Rees, the astronomer royal, warned in a lecture earlier this year that aliens might prove to be beyond human understanding.
“I suspect there could be life and intelligence out there in forms we can’t conceive,” he said. “Just as a chimpanzee can’t understand quantum theory, it could be there are aspects of reality that are beyond the capacity of our brains.”
timesonline.co.uk
Oops, that was a bad call, Earth
Some scientists want to send signals into space in search of aliens but others warn we may get more than we bargained forRichard Woods and Chris Hastings
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“CALLING all aliens, this is Earth. Are you receiving me?” Rather than simply listening for signals of extra-terrestrial life, some scientists are preparing to take a much more active approach to finding alien intelligence on other planets.
They believe we should start beaming regular signals into space specifically to find intelligent life, even though other scientists believe it could be an invitation to danger.
“My personal view is that being more active is a worthy strategy,” said Douglas Vakoch, director of interstellar message composition at the SETI [search for extraterrestrial intelligence] Institute in California. “There is more serious talk of it, though not at the institute level.”
At an astrobiology conference in Texas in April, SETI enthusiasts will discuss new methods of discovering extraterrestrial life, including sending out interstellar messages. Alexander Zaitsev, a Russian scientist who has already beamed out four carefully composed signals to nearby stars, has been invited to attend.
In the UK, Dr Marek Kukula, public astronomer at the Royal Observatory in Greenwich, said: “Part of me is with the enthusiasts and I would like us to try to make proactive contact with a wiser, more peaceful civilisation.”
However, he warns that advertising our presence could be risky. “We might like to assume that if there is intelligent life out there it is wise and benevolent,” he said. “But of course we have no evidence for this.
“Given that the consequences of contact may not be what we initially hoped for, then we need governments and the UN to get involved in any discussions.”
The issue will be among those raised at a two-day meeting at the Royal Society in London this week, under the heading, “The detection of extraterrestrial life and the consequences for science and society”.
Among the speakers will be Professor Simon Conway Morris, a Cambridge University evolutionary biologist, who says there is good reason to think aliens exist — and that they may well have chemical and biological similarities to us.
Conway Morris, whose talk is entitled “Predicting what extraterrestrial life will be like — and preparing for the worst”, said: “My basic argument is that, contrary to most neo-Darwinian thinking at the moment, evolution is much more predictable than people think.
“In particular, I would argue that the emergence, by evolution, of intelligence, cognitive capacity and all that stuff is an inevitability.”
In short, under the right conditions of a “biosphere” such as that present on Earth, the molecules necessary to form complex and intelligent life are already available; Darwinian evolution will do the rest.
“I think we can argue some intelligence must emerge in a biosphere,” said Conway Morris. “If that is correct — and it applies to manipulative skill — then that suggests there should be alien technologies.”
Astronomers have already discovered about 300 planets beyond our solar system, and some suggest it is only a matter of time before more Earth-like planets are identified.
That suggests there should be “lots of extraterrestrial civilisations around. At least that’s the principle, but where are they?”, says Conway Morris. Why have aliens not popped up — except in Hollywood films such as ET and Independence Day — despite decades of eavesdropping with radio telescopes?
The astronomer Heather Couper said: “My main worry is that our technology is simply not up to the task. Earth came into existence four to five billion years ago, but the oldest stars are twice that age. They may have life, but that life may be far more advanced than we are.”
Others suggest aliens may have good reason not to give away their presence. Weak electromagnetic signals have been transmitted from Earth for nearly a century in the form of radio, television and other transmissions. By now some should have travelled 100 light years out into space, though they will be growing fainter and fainter.
If aliens have picked up footage of, say, Bernard Manning or Simon Cowell, let alone the Second World War, they may have decided to keep quiet. “They may be very like us,” said Conway Morris. “I’m not sure I’d answer the telephone.”
However, the most likely explanation, he admits, is that there simply are no alien civilisations out there, perhaps because planets with biospheres are very rare.
Dr Robert Massey of the Royal Astronomical Society, takes a similar view: “If there were thousands of civilisations out there, I think we would have detected something by now. But that doesn’t mean we shouldn’t try.”
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