MICHELLE THALLER: Anthony, I often get asked this question: If scientists actually knew that there was an impending catastrophic collision, some asteroid was heading towards Earth, would they tell you? And the answer is yes. We actually study the sky; every night we're looking for objects that might be on a collision course with Earth and if we find anything that even looks risky we inform lots of people. The other thing is that the sky is available to anybody on the Earth – no one government owns the sky, there are telescopes everywhere on the planet; there's no way that anybody could hide the fact that some big asteroid was on a course with the Earth. So one of the things that I find very difficult as a scientist is people often ask the question: "Would scientists tell us if something really bad was about to happen?" And you think about that sentence and you have to ask the question: Who is the "us" here? Am I not part of "us"?

I remember back, I think it was in 2012, there was this idea that the Mayan apocalypse was going to come, that the world was going to end, it was all over the news and I actually got a phone call from somebody. I was sitting at my desk at NASA and somebody asked me the question, "Is the world going to end next week?" And I thought about that because, of course, we knew that the world was not going to end, there was nothing happening astronomically that we could tell, but I realized this person didn't think of me as an actual human being – that if I knew the world was going to end in a week I would be at work at my desk. I don't think so. The day you have all the scientists buy up all the great wine and max out their credit cards and disappear then you might want to worry, but even that's not how we work, we are people, and if we knew something dangerous was coming there would be no way for us to hide it.

Now, one of the things that NASA is researching right now is how to actually alleviate a bad collision. If we see a big asteroid coming toward us on a collision course there are actually many things we could do to avert the asteroid a little bit, have it miss the Earth, and we're studying those right now. But in the past, whenever we've even seen something that looked slightly risky, we've gone to the government about it, we've gone to the people, we've gone to the press. We have nothing to hide. And this is something that is really difficult in my life. People are saying: Are you hiding aliens? Are you hiding evidence of this? Are you hiding the fact that an asteroid is going to blow us up or whatever? And to me it speaks to the separation that somehow scientists are this monolithic, inhuman group that we could hide things, that we would want to. Instead we've been trying to involve the public in everything that we do. I know this will not convince the conspiracy theorists out there, but one of the things I love most about our science is how accessible it is and how much we would tell you even if something bad was going to happen.