Questions about the heavens are as old as civilization, perhaps as old as language itself. Is this universe infinite? What are the lights we see in the sky? In the millennia since our distant ancestors first looked up, these basic questions have been answered in countless ways, while other, more difficult questions have arisen and been answered in turn. This insatiable curiosity is fundamental to our nature, and as we learn more about our universe, we better understand our place in it. Astronomer Mark Kidger has spent his career helping the general public understand the nature of the universe and what astronomy can tell us about its composition, history, and future. In Astronomical Enigmas, he presents the questions he is asked most frequently and offers answers that are at once clear, succinct, and stimulating. Kidger begins by exploring the heavens from the perspective of our forebears, moving from Stonehenge and the earliest theories about the planets and stars to one of the great historical mysteries in astronomy: the identity of the star of Bethlehem. He then answers questions that provoke some of the most passionate and heated arguments between astronomers: Is there life on Mars? Is Pluto a planet? What did we learn by going to the Moon? He uses these questions to look at how astronomers deduce information about objects they could never visit. Finally, Kidger looks to the future by examining two urgent questions--the possibility that an asteroid might devastate life on Earth and the impact of climate change as witnessed on other planets--before coming full circle to look at our own origins, answering the question "Are we stardust?" The answer is as astonishing as it is unexpected. Witty, engaging, and accessible, Astronomical Enigmas is a terrific way for anyone who is fascintated by the skies to learn how much we know about our solar system--and how much there still is to discover.