IOP lecturer says life could be detected on another planet within 15 years

9 October 2015

There is a good chance of finding evidence of life on another planet within the next 10–15 years, and perhaps even finding it eventually in our own solar system, astrobiologist Dr Lewis Dartnell said at an IOP event held inside a tunnel in King’s Cross, London, on 8 October.

Dr Lewis Dartnell

  
At the packed public lecture he said he was optimistic about finding extraterrestrial life, at least in bacterial form, because of advances in robotic exploration, the large number of extrasolar planets now being discovered, and what we were learning about extremophiles – micro-organisms that survive in extreme conditions on Earth. These include bacteria that thrive in boiling hot acidic lakes that would kill human beings, others that live in icebergs at –20°C, and some that have been discovered in nuclear reactors, surviving radiation levels thousands of times higher than those that would be fatal for us.

The existence of this radiation-surviving species, nicknamed “Conan the bacterium”, and others living in conditions that were previously thought fatal for life, had made scientists realise that there were terrestrial bacteria that could survive on Mars, he said. Similar microbes might yet be found in other locations, such as in the liquid sea beneath the frozen surface of Europa, one of Jupiter’s moons, or in the geysers being squirted from Enceladus, a moon of Saturn, Dartnell believed.

He would love to be able to bring back bacterial life from Mars or one of these moons and study it on Earth, he said, to see if it was based on DNA, whether it was built using proteins, or whether it was truly alien. “For me as a biologist, that would be about the most exciting thing I could imagine.”

Dartnell, who is a research fellow based at the University of Leicester and funded by the UK Space Agency, explained that astrobiology was a serious science. “It’s not UFO-spotting or waiting for aliens to abduct you – I don’t even own an anorak,” he said. The findings he was discussing were at the cutting-edge of real science, and he hoped for further discoveries from missions such as ExoMars, which is to launch in 2018.

There had been discussion of a mission to explore the liquid methane lakes on Titan, he said, put forward by IOP Council member Professor John Zarnecki, who was in the audience and confirmed that the proposal would be resubmitted next year.

In a question and answer session, Dartnell was asked whether chemicals such as methane might be an alternative to water as the basis for life. Methane had been found to be “rubbish” for this purpose, though liquid ammonia might be a possibility, he said. It was also unlikely that an element such as silicon could replace carbon in such processes as building cells, he said.

He was also sceptical about whether intelligent life was common in the universe, though bacterial life might be. “However, I would really love it if I got an extraterrestrial message tomorrow,” he said.

Astronomer and science communicator Dr Francisco Diego, who was also in the audience, asked whether the fact that humans seemed to be alone in the universe, and had been extremely lucky to emerge after the mass extinctions of species on Earth, should make us concerned to be more protective of our environment. Dartnell said: “I agree entirely. From this we should learn more about our world and how to take care of it.”

Dartnell’s lecture had been held in the tunnel partly to demonstrate how future colonists of Mars would have to burrow beneath the ground to escape cosmic rays, he said. They would have to live off what could be extracted from or grown on the ground on Mars, and the technologies required for sending robotic missions there could have spin-offs in developing lightweight, low-energy equipment for places such as rural Africa, he said.

The IOP’s chief executive, Professor Paul Hardaker, said the IOP’s next public lecture would be held in January and updates would be given on Twitter, Facebook, and the IOP’s website.