As NASA's Earth Observatory Web site describes: "Each year, the North Atlantic Ocean announces springtime by producing 'blooms' large enough to be seen from space." While scientists have had satellite images of these phytoplankton blooms for years, researchers can now detect biofluorescence from these microscopic organisms, with important implications for monitoring the environment. The Web site presents some of these incredible images, along with an interesting essay on the topic (which includes a handy hypertext glossary).