The remarkable thing about the whole history of space exploration is how few disasters there have been, considering what is involved.

I hope that this sad accident isn't used as a reason for the USA to turn its back on space, or to totally militarise the space programme. Indeed, there is a logic in the argument that it'd be better to spend that effort and money on things closer to home, on Earth. But I've always felt that the possibility of moving out from Earth and seeing the planet as a small precious and vulnerable place, where humans have absurd quarrels which threaten to wreck it is perhaps a more realistic way of moving us forward.

I've got a peace badge with a picture of the Earth from space. I think that picture has maybe done more to help people recognise our unity than anything else in history.

If you think about the sad story of "the peace dividend", it is fairly clear that, if the money spent on space exploration was diverted, it wouldn't go to help the poor, it'd just end up with people who already have far more than is good for them. And the world as a whole would be poorer.

It's 17 years since the last space tragedy. Yes, it's sad, but exploration has always been dangerous, and when it takes its price, that's no reason to give up. It's a reason to learn what can be learned from what happened, and use that for the future.

As Joe Hill put it, in a rather different context "Don't mourn - organize."