Caleb Scharf was born and educated in England. He received his B.Sc. in Physics from Durham University, and his PhD in Astronomy from the University of Cambridge. Following postdoctoral work in X-ray astronomy and observational cosmology at the NASA Goddard Space Flight Center and the Space Telescope Science Institute in Maryland, he has been a research scientist at Columbia University, New York. He is currently Director of the multidisciplinary Columbia Astrobiology Center. His research interests include the study of exoplanets, exomoons, and the nature of environments suitable for life.