Robert Inventor

When Curiosity's successor and the ExoMars rover land on Mars around 2021, we will see two different approaches to the search for life on the planet side by side. NASA's mission is the first stage of a sample return program. The ESAs ExoMars rover (in partnership with Russia) will explore Mars in situ for biosignatures as well as drill two meters below the surface. Which is the best approach? A sample return would be great for geology. But would it help with the search for life on Mars? Or is it more of a technology demo for this?

One day you feel a strange stinging, biting or crawling sensation beneath your skin, which just won't go away. Then fibres begin to protrude from the skin or you may see red or blue lines below the surface of your skin. Eventually sores erupt all over your body, including in places you can't reach such as the middle of your back. You go to the doctor - and - after doing tests to rule out many other similar conditions, he finds that you fit the symptoms of a very rare condition, popularly called "Morgellons". He or she then tells you that this is not a real disease, but rather is a delusional condition. There is nothing physical causing this. It's just something going on in your mind which leads to all these symptoms.

This is a question that is frequently asked on Quora, with a different date each time. We get a fair number of quite worried people asking this question, in all seriousness, concerned that Earth is about to be hit by a giant impactor. Sometimes they have read sensational stories by online papers that should know later. It is easy to keep up to date with potential impact dates by visiting this page, automatically updated for the Sentinel program: Current Impact Risks. Just look and see if there are any entries coloured orange or red. Then look for the predicted date of impact. So far this has never happened.

Many discussions of extra terrestrial intelligences suppose vastly superior intelligences, that think of us like ants. And show no compassion for us, don't even notice us. So - first of all I think there is no particular reason for ETIs to be more intelligent than us. They could easily be less intelligent. But also - if they did treat us as like ants, then they'd be in need of help from us. Many discussions of extra terrestrial intelligences suppose vastly superior intelligences, that think of us like ants. And show no compassion for us, don't even notice us. So - first of all I think there is no particular reason for ETIs to be more intelligent than us. They could easily be less intelligent.

This is a question which was asked recently on quora: Is it possible to have a moon so reflective that when it reflects the light of the sun, it will be as if it is daylight? Anyway it is a rather fun problem, easy to work out by "back of the envelope calculations", and the answer takes us to some interesting areas of planetary physics.

So, you think you know what a planet looks like? A sphere, perhaps flattened at the poles? But if you've been following recent discoveries of dwarf planets, you may know that rapidly spinning dwarf planets like Haumea typically are rugby ball shaped (triaxial spheroids), rather surprisingly perhaps. So, what other shapes can a planet have? Theory, and experiment with droplets in simulated zero g suggest several exotic possibilities.

 This is a draft of my presentation for the think tank this summer on exploration of Enceladus and Europa for signs of life.

I wrote this when New Horizons was approaching Pluto, and expected to find new moons and possibly a ring system. So, just as a fun question to hook this post on, I asked, could it find a moon of a moon? Or a moon with rings?

This is a commonly used argument, indeed often taken for granted. We can simulate physics on a computer. So, the argument goes, what is to stop us eventually simulating your whole body including your brain? And if so, is it not just a matter of time, and increasing computer power before we have exact simulations of humans as computer programs? Programs whose behaviour is indistinguishable from humans?This is a staple of many science fiction stories of course. But some logicians, philosophers and physicists think there are flaws in this argument.We know the laws of physics are incomplete. Could there be physical processes which for some reason are impossible to simulate using a computer program? And could processes like that go on in a human being?

Elon Musk says he wants to create a backup of Earth on Mars, and several brilliant people have suggested this should be one of our main objectives for sending humans into space, not only Elon Musk. Perhaps most notably, Stephen Hawking. But being brilliant doesn't mean you are always right in everything you say, or that what you say can't be questioned by anyone else!There are other good reasons for space settlements - but would any of them be of any value as a "backup" any time in the next few hundred million years? 

Elon Musk says he wants to create a backup in space, and Stephen Hawkins also says that humans have to move into space to survive. For some reason, hardly anyone seems to question this. I can see many good reasons to have space settlements, and eventually indeed Earth will become uninhabitable  but can't see any value of them as a "backup" any time in the next few hundred million years.So, first of all - it's important that you can access your backup when you need it. If someone offered to write important files to a DVD and send it to the Moon - or even to interstellar space - what is the point in that? If anything goes wrong we have to send an expedition to recover the data before it is any use to us.