23 January 2010 | NewScientist | 3

SHOULD we break our interstellar silence? In the 50 years we have been scanning the skies in search of extraterrestrial intelligence, all we have heard is a whole lot of nothing. We have even sent a few hopeful transmissions into space, to no avail. Now some SETI researchers are suggesting that we take a more active approach and systematically advertise our existence to the cosmos (see page 28).

Others say this would be rash, and that to shout into the dark is unwise when we have very little idea who, or what, is out there. There’s a good evolutionary argument that any intelligent alien species is likely to be predatory (see page 31). While it is far-fetched to worry that they will want to prey on us, they may, like us, have aggressive tendencies. Physical invasion is improbable, but electronic warfare could be waged across the light years in the form of computer viruses or even intelligent avatars.

Cosmic culture shock is a more likely consequence. When two human civilisations with very different levels of technology make contact, the less technologically developed one tends to come off badly. While that does not bode well for us, especially if ET’s civilisation has had millions of years to evolve, the optimists hope that

Hello ET, we come in peace

EDITORIAL

sophisticated extraterrestrials will know how to cushion the culture shock while still showing us their marvels.

These arguments and more will be debated next week in London at a meeting of the Royal Society . It will not be the first time the issues have been aired, and nobody expects a firm conclusion, but simply talking them through could encourage us to develop some vital humility. Contact is most unsettling for cultures who think they are the centre of the universe, so we would be well advised to prepare ourselves for the revelation that in galactic terms humanity is

merely one small and backward tribe. So should we try to promote contact by

broadcasting our presence to the heavens? If alien civilisations exist, they are likely to be so far away that our message will not arrive until after we are gone. In that case, what is there to lose? We might as well let them know that we used to be around.

If, by chance, there are intelligent aliens within a few tens of light years from Earth, their own SETI programmes might already have sniffed us out, by picking up the spectral signs of industrial pollution in our atmosphere, or tuning in to our broadcasts. It is not inconceivable that our presence has already been noted by some nearby alien civilisation. So let’s make some friendly overtures, rather than leave them to wonder why we’re not transmitting, and what we’ve got to hide. ■

The advantages of advertising our existence to the universe outweigh the risks

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A DECADE ago, researchers showed that slime moulds could solve a maze. Much speculation followed that these single-celled organisms were displaying a rudimentary form of intelligence – one that might ultimately underpin our own.

Now, similar claims are being made for a blob of floating oil (see page 8). It is a stretch to call the blob smart – it just gives the appearance of intelligence by responding to ordered information in its environment. Even so, some researchers see “deep connections” between blob intelligence and our own.

Intelligence is hard to define, and even harder to subject to reductionist science. Even so, we know it must somehow arise from physics and chemistry. Deep down, we’re all blobs. ■

Blob intelligence is not unlike our own

Get a drop of gravity

AS EVERY schoolchild knows, the concept of gravity came to Isaac Newton after a close encounter with an apple – or so the story goes. Older students go on to learn Einstein’s view of gravity: that masses warp space-time like a ball on a rubber sheet. Now we could be closing in on an explanation of where gravity comes from: it might be an emergent property of the way objects are organised, much as fluidity arises as a property of water (see page 6). This idea might seem exotic now, but to kids of the future it might be as familiar as apples. ■

“It is not inconceivable that our presence has already been noted by some nearby alien civilisation”

GEOLOGY Rebuilding Haiti’s

houses The multi-storey concrete

buildings that made up much of

Port-au-Prince turned into death

traps when the earthquake struck,

but constructing new shake-proof

buildings is not as expensive as you

might expect

TECH Networked airbag

could save skiers If an

avalanche catches a group-member

unawares, fellow skiers can save them

by inflating their airbag remotely

SCI-FI Images of space-age

dreams From Russia’s

cosmonaut training facility to NASA’s

Apollo control centre, our gallery takes

you inside the space industry – but with

a twist. Photographer Vincent Fournier

goes beyond documentary images,

mixing reality with fiction to create a

dream-like, retro-infused world

ZOOLOGGER The amphibious

mystery cat Zoologger is our

new weekly column highlighting

extraordinary animals – and

occasionally other organisms –

from around the world. This week

a cat with webbed feet that just

loves water

NEUROSCIENCE Empathising

with robots Exposure to robots

in movies and on television could

give the next generation the ability

to empathise with our artificial

counterparts. That’s according to a

study of the brain regions that are

involved with our ability to relate

to each other

TECH Interactive greeting

cards A new approach to

greeting cards turns electronic

circuitry into art and presents the

recipient with an interactive treat

MOTION Flash, whoosh, blur:

movement through the ages

Images from a London exhibition

follow attempts to capture movement

in science and art through history

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