How do scientists today study life on Mars? One critical way is by studying the environments on earth that most closely mirror what scientists know and theororize about the biology of our nearest planetary neighbor. Pamela Turner’s account of astrobiologist Chris McKay’s work and research describes experiments he has conducted in some of earth’s most inhospitable and challenging climates, from frigid Antarctic ice and oceans to near-barren deserts to lush—and very buggy—Siberian forests. Today, because of his research, McKay advises NASA on where to land space probes, based on his theories about which regions of Mars are most likely to show signs of life. Turner writes with humor, including quirky subheadings and chapter titles such as “Rip Van Microbe: Siberia, Northern Russia.” McKay’s personality also comes through. His hope is that if life is ever found on Mars, it will be different from life on Earth. “Truly alien life would be a lot more interesting. It would mean that there are lots of ways to get going in this universe. Who knows what we’ll find?”Ample photographs of McKay’s expeditions illustrate each chapter in this outstanding science volume. (Age 10 and older)