Signs of life
Over 140 years after Giovanni Schiaparelli saw canals on Mars, Nasa seeks aliens in a lake bed.
- While Elon Musk hurls cars into orbit for fun, Nasa has sent a car-sized rover to Mars in deadly earnest. Perseverance is headed for the Jezero crater, which is believed to have been once filled with water, the first principle of earth-like life.
- It will bring back ancient clay deposits from the lake floor, which will be examined for traces of ancient Martian life, from before the planet turned into a desert. It is presumed that the natives, if any survive, are friendly, and that Perseverance will not be carjacked by little green men.
- But little green men are absurdly anthropomorphic. If humans do encounter life outside our world, they may not even recognise it as living.
- It may have developed with a different biochemistry and genetics, and different gravity, pressure and temperature would have moulded the outcome.
- On Venus, whose surface is hot enough to melt lead because of a runaway greenhouse effect, science fiction might imagine life forms with molten metal coursing through their veins. And in deep space? There could be Vogons and Klingons, and the dragons of Eden.
- Researchers at two US universities have recently proposed a widening of the concept of life into the unknown — to “lyfe”. To qualify, lyfe must be able to manage energy, grow, maintain its internal environment (like we maintain body temperature) and record, process and act on information.
- Interestingly, apart from space aliens, a nightmare artificial intelligence which operates autonomously — precisely the one which Elon Musk and Stephen Hawking had raised the alarm about — could probably tick all those boxes.
In that case, we would not have to send a rover the size of a sedan all the way to the other planets in search of alien life. It could be right here on earth, dreaming of impossible futures in its silicon brain.