The Universe Around Us

An Introduction to Astrobiology

What does life need? Extreme Life Habitable Zones Planetary Protection Solar Observations Lunar Observations Other Observations Comets Asteroids Nebulae Stars Galaxies Our Universe Extrasolar Solar System SETI Mercury Mercury Venus Earth Moon Mars Jupiter Jovian Moons Saturn Uranus Neptune Dwarf Planets NASA website SETI website For Educators Games Definitions