Martin Rees: Mars probes and science in society

Chris Smith asked Martin Rees about recent developments in the exploration of our Solar System...

Martin - It's true. Robots have advanced hugely in the last few decades. I think that advance weakens the practical case for sending humans into space because humans are fragile. To send a robot to Mars of course isn't a hugely big deal. It just hibernates on the way. Whereas to send a person to Mars involves six months of food and the provisions to bring them back so it's hugely expensive. The cost gap is enormous and it's true that robots can't do what a human would do. There are some robotic vehicles crawling around on Mars. There's one called Curiosity that was launched and got there about 12 years ago. That trundled very slowly across a big Martian crater because it had to report back to base if it wanted to change direction if it encountered an obstacle. The later one called Perseverance has enough intelligence to work its way around obstacles, but you can't do geology. But within 20 years one can imagine that there could be a probe which can study what's a good place to dig and actually get the samples itself.

Chris - Can we talk politics for a minute? Because one of the things that you did in the last decade or so, you joined the House of Lords. Robert Winston mentioned to us that you'd talked to him before you did that when we spoke to him. Why did you decide to go down that road? Had you always been quite politically active? Did you have a particular plan in mind with doing that?

Martin - Well, I'd always been fairly politically active. It was an opportunity when I had the chance to join the Lords as a cross bencher.

Chris - Are there many scientists in your number in the Lords, though? We've seen so much of this in the last few years, haven't we, where we are being told that we're following the science and so on? But in fact, when you look for ability to guide a lot of this, there are not many of them?

Martin - That's right. But I'd say one has to distinguish the science itself and the consequences and how its consequences are implemented. Of course there are lots of issues like embryo research and things like that. And of course, dealing with pandemics when there's a choice of policy options. Although the politicians should have the best scientific advice during the pandemics, then the choice involves economics, politics, and ethics. And in those arenas, the scientists have no special expertise.

So I think there's a transition in any public debate between getting the science as right as we can and then, when we know the science, that still opens up a range of options. It did in the case of the pandemic. Are masks a good idea? Should we shut down the schools? Those are more general issues than just science. The same is true in defence research and things of that kind. I think we need to ensure that the best science is taken advantage of, and also that the public and politicians in particular are aware that much of science is provisional. Some sciences are pretty well understood and get better understood. In the early days of the pandemic, it really wasn't clear exactly what was the right thing to do, but the scientists equipped themselves well in developing vaccines quickly, that's true. In climate science, 20 or 30 years ago, it was genuinely very uncertain, whereas now the basic outlines are pretty certain, but that leaves open the question of the trade off between adaptation and mitigation and all that. More and more of the issues of politics have a scientific dimension, and that's why we do need more scientists - I'm not denying that - in politics.

But we also need better education, because one of the problems is that it's all too easy for someone to be bamboozled by bad statistics and things like that. We should be grateful for people like our friend David Spiegelhalter, who did a great deal to explain very clearly what one can believe and false positives and all that sort of technicalities in statistics. We need people like that and I think it's sad if the public doesn't understand the basic aspect of nature, why the seasons occur, but I think scientists shouldn't bemoan ignorance among the public of their subject too much because, frankly, the public is ignorant about too many things. It's sad if the public doesn't really understand Darwinian evolution, but it's just as sad if they don't know their nation's history and can't find Gaza or South Korea on a map. And many people can't do those things. So I think education is something where we do need to focus on and aim for higher standards.

Chris - You wrote two books in the last year or so? What are your plans for the year ahead?

Martin - Well, I'm writing two more at the moment. One is on the big unknowns in science, and I've got to try and humanise this by putting in some short sketches of the interesting and successful scientists who I've been privileged to know. And another short book with a collaborator called Alan Lightman on what it's like to be a scientist, a more subjective one.

Chris - I look forward to reading them and then coming and interviewing you about them when I've been through them.

Martin - Right. Well, thank you very much.