This post is being written in the spirit of the Carl Sagan "Blog-a-Thon".
I'm not really one to do the hero thing, not to any great extent. There are people ("famous" and "non-famous") whose ideas and actions have impressed me, people whose opinions matter to me, but I'm not sure I'd go all the way and say "hero".
If anyone came close it would be Carl Sagan.
Unlike many people who'll be writing something about him today (the 10th anniversary of his death) I don't really have a long list of memories or anecdotes about his work and its impact on me, but two key things do stand out.
The first is (no surprise here) Cosmos. I'm struggling to remember when I actually watched it, I'm pretty sure it was the early 1980s (on the BBC). I'd been rather obsessed with all things astronomy and space for quite some time so, as a young teenager, it felt like the programme had been made just for me (it was also a very welcome change from The Sky at Night). It's hard to describe the impact the programme had on me, about the best I can manage is to say that my interest in astronomy was reinvigorated and I've got a recollection that it was partly responsible for me finally deciding that I had to get out and actually observe.
The other key moment for me was when I first read The Demon-Haunted World. I was quite late to the book. I'd owned a copy for a number of years and, like with many books, it had sat on my (rather too large) "to be read" pile. Finally, in early 2002, just before my son was born, I got around to reading it (right after finishing Dawkins' Unweaving the Rainbow). The book had a huge impact on me. It wasn't a case of it helping me form an opinion on the subjects covered in the book — I had enough of those — it was the fact that someone had managed to write down those ideas and opinions in a clear and easy to follow way. It was, for me, an example of what Carl Sagan did best: communicate clearly.
As a father-to-be I was faced with many concerns that, until that point, hadn't really bothered me before: issues regarding education and communication, issues regarding how society conducts itself, issues regarding the acceptance of idiocy and superstition. Sure, I'd thought about these things and held opinions on them (some informed, some not so well informed), but the prospect of being directly responsible for another individual meant that they were right on my doorstep. That's why the (accidental) timing of my reading of tDHW meant so much to me: it helped me better understand my concerns, my worries, my opinions, and it did it carefully and clearly. Right book, right place, right time.
Other than the two experiences noted above, I should probably also say that I'm a fan of the novel Contact, and also the film based on it (yes, even though it's rather different from the book).
In a world where pseudo-science and superstition still have a hold, where many people still seem to think that such things are worthy of respect and equal treatment, clear communicators and advocates of the scientific method help hold back the tide of nonsense. Thankfully Carl Sagan left a body of work that should help maintain those defences.
Those afraid of the universe as it really is, those who pretend to nonexistent knowledge and envision a Cosmos centered on human beings will prefer the fleeting comforts of superstition. They avoid rather than confront the world. But those with the courage to explore the weave and structure of the Cosmos, even where it differs profoundly from their wishes and prejudices, will penetrate its deepest mysteries.
— Carl Sagan, Cosmos.
Ian 
