I should teach the world that science is not right or wrong, is not good or bad, is never as clear-cut as commentators often make it out to be, and does not have final answers. Science makes progress towards answers, and that progress is a series of steps - occasionally big steps, but more usually small steps.

Scientists often disagree, over the interpretation of data, but one scientist is not right and the other wrong. They are not arguing - just debating, to make matters clearer, which will lead to another step forward. Science is never finished, and science is always full of surprises. The next surprise is just around the corner - only you do not know which corner.

Monica Grady is author of Search for Life (buy this book from Amazon (UK)). See her website.