- We frequently hear about some discoveries of exoplanets like our earth or of earth twins. How common are earth like habitable planets in the universe?

-  The short answer is we have no idea how common they are because it's at the edge of our technology to even detect an earth-sized planet around a sun-like star with an earth-like orbit. And so we're just at the edge of being able to detect planets like that. Even once we detect a planet like that, we don't have the technology to determine whether there is water on the planet or not. We can't tell whether there are continents, we don't know what its rotation rate is. And so we're just beginning to measure the very basic parameters of whether a planet is earth-like. Does it have the same kind of orbit, is it the same size, and does it orbit a star like the sun? But that really doesn't answer the question of how common are earth twins. I suspect over the next thirty or so years we'll develop that technology. And I think what we are going to find there is going to be planets that look increasingly like earth but then it allows us to answer the real question we want, is there life out there? And my suspicion is, my prediction is what we will find is that we will find planets that look increasingly like earth but there is going to be very little or no life on any of those planets until effectively you get something that looks almost exactly like earth. And that's going to be a sign that God has created life somewhere else as well.