Sir Martin Rees on stars, science, and signs of life

Sir Martin Rees, UK Astronomer Royal, was once asked if his job was to do horoscopes for the Queen of England. “If she wanted one,” he replied, “I suppose I’m the person she’d ask.” Her Majesty hasn’t asked, so Rees has worked in astronomy, not astrology. Lately, however, the allure of distant stars and galaxies is tempered by his concerns over much more terrestrial matters.

In his latest book, On the Future: Prospects for Humanity, Rees explores how humanity’s rapid technological advances are threatening – and may ultimately vouchsafe – our survival as a species. After delivering a public lecture at Perimeter Institute in October, Rees sat down with Inside the Perimeter to discuss why he believes science, not star signs, provides our clearest glimpse into the future.

Inside the Perimeter: As an astronomer, what has inspired you to turn so much of your focus to life here on Earth?

Martin Rees: Well, I think many people whose work is focused on certain topics are at the same time citizens who, maybe in later phases of their life, have a different focus in their activities. I’m old enough to have remembered campaigning at the time of the Cuban missile crisis, and I’ve been interested in arms control ever since then. Later in my life, I’ve had the opportunity to engage with science policy. So my work has led me to become more engaged in general topics, [such as] the impact we are collectively having on the planet and the downsides of our more powerful technologies.

Inside: What are the questions currently keeping you up at night?

Rees: I worry about the huge gap between the way the world could be and the way it actually is, about how to improve the lot of underprivileged people. In terms of science, I’m fascinated with how science is a progressive enterprise in which ideas start off as being speculative, and eventually firm up to become part of a consensus. If I look back over my career, many issues that were speculative when I was starting – even the idea of the big bang was speculative back then – are now developed to the stage that we can talk with great confidence and few-percent precision about how our universe evolved, all the way back to when it was a nanosecond old. That’s huge progress. And now the questions we are trying to address couldn’t even have been posed decades ago.

Inside: Which currently speculative questions do you think we may soon answer?

Rees: The question I’m most often asked when people know I’m an astronomer is: “Are we alone? Is there life out there?” We can’t answer that at all now. We have no idea whether life on Earth started as a rare fluke. But in 10 years, we will have some evidence thanks to the next generation of telescopes, which will have the light-gathering power to say something about a planet orbiting another star – whether it has continents and oceans and oxygen in the atmosphere. So we will know, perhaps within 10 or 50 years, whether there are other planets with life on them.

Inside: In 1968, the astronaut William Anders took the iconic “Earthrise” photo, showing the Earth hanging in space. If we look ahead 100 years from that moment, and people in 2068 see that image of a planet that harbours life, what do you think it will mean for humanity?

Rees: It may sort of make us cosmically more modest as compared to if we really thought that we were alone. Or it could be that we are unique. But even if we are unique, that doesn’t mean life will forever be a trivial feature of the vast universe. The one thing we know as astronomers is that the future is longer than the past. As Woody Allen said, eternity is very long. That means that even if life were now unique to the Earth – which is logically possible – then there’ll be abundant time for progeny descended from humans to spread through the galaxy.

Inside: Your latest book is about the grave existential threats unique to the present day, yet you remain optimistic. How do you maintain that optimism?

Rees: Well, I am rather pessimistic about whether we’ll get though this century without some setbacks caused by the fact that the global village will always have its village idiots, and now just a few of them can cause a disruption and breakdown in society. If enough of the public is energized, I think political responses can be positive. Only if these issues are prominent in politicians’ inboxes and in the press all the time will politicians prioritize them. So there is reason for pessimism, but if we can deploy science effectively and have the right trade-off between security, liberty, and privacy – to avoid the bad actors from becoming too dominant – then I think we do have reasons for optimism.

Inside: Is that why you speak to the public and write books – to help deploy science effectively?

Rees: It is important for a good democracy that people understand science, to have informed judgment and not be bamboozled. And it is a worthy goal to understand the universe of which we are a part. Our lives today, for the average person, are better than any previous generation, and that is due to the applications of science. Science has been the basis of the lives we enjoy. But being so empowered by science raises the stakes: we can do wonderful things, but the potential downsides are serious. So scientific interaction is very important, and it depends on places like Perimeter to encourage public interest in science. Science is the most universal part of our culture, able to transcend barriers of faith and nationality more easily than other enterprises can.