Extraterrestrial Life Organic Molecules Building Blocks of Life Water on Earth Extraterrestrial Environments Organic Compounds Conditions for Life Water Distribution Extraterrestrial Water Chemical Signatures Nutrient Cycling Environmental Changes RNA Primitive Life Forms Terrestrial Hot Springs Environmental Conditions Extraterrestrial Materials Cosmic Materials Chemical Processes Chemical Building Blocks Chemical Reactions Mars Exploration Cosmic Water Water in the Universe Microbial Life Extraterrestrial Influences Delivery of Organic Material Seeds of Life Carbon-Rich Asteroids Water-Bearing Clay Minerals Water Delivery to Earth Carbon-Based Life Seeding from Outer Space Essential Ingredients Building Blocks Extraterrestrial Impacts Prebiotic Chemistry Early Earth Conditions Life Beyond Earth Hydrothermal Vents Chemical Evolution Asteroids and Water Extraterrestrial Chemistry