I'll be on David Livingston's the Space Show this Friday, 27th May, to talk about my new "Case for Moon". It's main themes are: first, the Moon as our natural first destination in the solar system. Then, planetary protection and biologically reversible human exploration as core principles for human space exploration. Then, the Moon as a gateway for human exploration of the entire solar system, not just Mars.

Are you keen on humans in space, but skeptical about colonization of Mars as our first objective for space exploration? Do you think we will start with settlements supported from Earth, such as we already have in inhospitable places such as Antarctica? Do you think our exploration should be open ended with science as a core objective, and planetary protection and reversible biological exploration as core principles?

If you are keen on Mars colonization, it is not hard to find a future vision to inspire you. Elon Musk has plans to send a hundred people at a time in his proposed "Mars Colonial Transporter" and found a city of 80,000, and eventually a million. He is due to reveal these plans at the IAC conference this September.

This is one of the questions I get asked most often since I started to cover the topic of asteroid impacts. Will humans will become extinct within a decade, or within a century? And can this happen through natural disasters? For instance if you watch the movies you may think there's a chance of a giant asteroid impact which will make us extinct. But what's the real situation? 

In case you haven't heard of it, Nibiru is a totally nuts idea. Yet it gets many people very scared. I started to get messages about it as a result of writing articles about asteroid impacts, and how we can detect and deflect asteroids. It is possible to have beliefs that don't make any sense if you look at them closely. For instance, if you believe that you can have a square with every point on its edges equally distant from its center in ordinary geometry - that's impossible. That's a square circle. Nibiru is a belief of this sort.

I wrote this soon after ExoMars's successful launch to Mars, 2015. Hurray! In the program about the mission, before and during the launch, the presenters talked about the care they take to sterilize the lander of microbes to protect Mars. And indeed, kudos to all the space faring countries, and the planetary protection officers, for doing this. But in the same program they talked about ideas to send humans to Mars, talking about all its benefits. For some reason it never seems to occur to anyone to ask if humans can be sterilized in the same way as robots. There is nothing unusual about this - it's the same for programs from NASA, or programs about Mars on UK television, and anywhere.