Until very recently, planetary scientists had thought that Mars is a cold, dry planet. Then in the summer of 2000, NASA released images from the Mars Global Surveyor showing evidence of very recent seepage of ground water from crater and valley slopes in the planet's southern hemisphere. It seems that substantial reservoirs of the water that once may have run so copiously on the surface may still ... Full description.

Wilson Alwyn Bentley (1865-1931), famous for his photomicrographs of snow crystals, prepared sets of glass lantern slides of dew, frost and ice crystals. Many of these sets found their way to colleges and universities around the United States. The University of Wisconsin's Department of Atmospheric and Oceanic Sciences donated their collection to the Schwerdtfeger Library in 2000. Shortly after, the ... Full description.

The purpose of this activity is to construct a model that will provide students with a visual representation of parts per billion. Students work in teams to construct cubes of different volumes and to compare them to get a feel for parts per million by volume and parts per billion by volume. The intended outcome is that students gain a feeling for the small quantities of gases, such as ozone, present ... Full description.

The Antarctic ice sheet changes in size over the course of a year. When it is summer in the southern hemisphere, the ice sheet decreases in size. As the ice sheet melts, it releases fresh water into the ocean. In the southern winter (our summer), the ice refreezes, drawing fresh water out of the surrounding ocean, leaving the salt behind. These seasonal changes in the ice sheet are examined in this ... Full description.

This article describes how astronomers from the European Space Agency (ESA) have discovered thermal emission lines from interstellar water vapor using the spectrometers aboard ESA's Infrared Space Observatory (ISO). Full description.

NASA and Russian scientists have been selected to take the search for life in the solar system to the frozen reaches of Earth. Life forms (from diatoms and bacteria to mammoths) preserved in the Siberian permafrost can yield evidence about how life has changed on the molecular level and provide a treasure trove of ancient enzymes, proteins, and biochemicals. The ecosystems of the ice and permafrost ... Full description.

This article discusses the necessity of locating water ice as astronauts explore the solar system, for oxygen and fuel as well as for drinking. Topics include the possible occurrence of ice at the lunar poles and in comets, and some of the National Aeronautics and Space Administration (NASA) missions to locate it. Full description.

This site provides a discussion of the downward movement, or infiltration, of water from the surface into soil or porous rock. Graphics illustrate the processes affecting infiltration, including precipitation, soil characteristics and saturation, land cover, slope, and evapotranspiration. Links to additional sources of information are also provided. Full description.

NeMO studies the dynamic interactions between submarine volcanic activity and seafloor hotsprings at an observatory called Axial Seamount. The research activities at NeMO provide an extraordinary educational opportunity, both from the daily reports from expeditions at sea and from creative learning materials based on NeMO results. The site features curriculum materials designed for high school and ... Full description.

This booklet provides a brief introduction to the concept of plate tectonics and complements the visual and written information in This Dynamic Planet, a map published in 1994 by the U.S. Geological Survey (USGS) and the Smithsonian Institution. The booklet highlights some of the people and discoveries that advanced the development of the theory and traces its progress since its proposal. Although ... Full description.