This satellite image shows the brown sediment-laden water of the Mississippi River mixing wih the dark blue water of the Gulf of Mexico following a rainstorm. The city of New Orleans and Lake Ponchartrain can easily be discerned near the center of the image. Full description.

Visitors to this site can view satellite imagery and read an account of how remote sensing was employed to evaluate the extent of flooding and sediment load in rivers on the coastal plain of North Carolina as a result of Hurricane Floyd in September, 1999. This feature is part of NASA's Earth Observatory, a publication that focuses on Earth's climate and environmental change. Full description.

Vortices of water, called "eddies," form off the northwestern coast of North America in the winter, and are particularly large during El Nino winters. Users can read and view satellite imagery which explains how these eddies carry nutrient-rich water offshore, providing nourishment for phytoplankton, microscopic plants which form the foundation of the marine food chain. This is part of NASA's Earth ... Full description.

A study of the geology of Mars should reveal answers to such questions as how Mars developed into the planet we see today and what accounts for the differences and similarities between Earth and Mars. Visitors to this site can learn about ancient magnetism recently discovered by the Mars Global Surveyor that suggests the planet was once more dynamic and Earth-like with a magnetic field shielding the ... Full description.

After Antarctica, Greenland's ice cap contains the second largest mass of frozen fresh water in the world. Based on new research using NASA's airborne laser altimeter, scientists have identified pronounced thinning of Greenland's ice cap. This new research indicates enough ice loss to cause a measurable rise in sea levels. This site, produced by NASA's Scientific Visualization Studio, features text, ... Full description.

Deserts are classified by their location and dominant weather pattern into several types: trade wind, midlatitude, rain shadow, coastal, monsoon, or polar deserts. Former desert areas presently in nonarid environments are paleodeserts, and extraterrestrial deserts exist on other planets. This site, produced by the U.S. Geological Survey, describes each type of desert using text and photographs. Full description.

This is the table of contents listing for the NASA booklet "Shedding a New Light on the Universe". Each item in the table is a link to a specific topic. Topics include such items as the electromagnetic spectrum, frequency, wavelength, and energy activity, the multiwavelength Milky Way, the Crab Nebula in different energies, spectroscopy, satellites and their parts, and the Rossi X-ray Timing Explorer ... Full description.

This site consists of JPEG images of the planets, including photographs of Jupiter, Mars, Saturn, historic photographs, and artistic illustrations (montages). Links to other parts of the GRIN image library are provided. Full description.

This resource provides a network of links related to a wide variety of images, photographs, and other multimedia resources from NASA archives. The site is browsable by subject, NASA Center (Goddard, Johnson, etc.), and by keyword. It also includes links to other NASA images sites. Full description.

Studies of the chronology of martian meteorites can distinguish various events in the history of the meteorites and give ground truth to Martian geology. This article discusses the use of radiogenic isotope dating to distinguish impact ages, establish exposure ages, define ejection times of meteorites from Mars, and establish terrestrial ages, which begin with the arrival of the meteorites on Earth. ... Full description.