Dunes and Dust in Arabia Terra

The battered region of Arabia Terra is among the oldest terrain on Mars. A dense patchwork of craters from countless impacts testifies to the landscape's ancient age, dating back billions of years.

In eastern Arabia lies an anonymous crater, 120 kilometers (75 miles) across. The floor of this crater contains a large exposure of rocky material, a field of dark sand dunes, and numerous patches of finer-grain material, probably dust. The shape of the dunes hints that prevailing winds have come from different directions over the years.

This false-color image, made from frames taken by the Thermal Emission Imaging System (THEMIS) aboard NASA's Mars Odyssey orbiter, shows the center of the crater's floor. The image combines a daytime view at visible wavelengths with a nighttime view at infrared (heat-sensing) wavelengths, thus giving scientists clues to the physical nature of the surface.

Fine-grain materials, such as dust and the smallest sand particles, heat up quickly by day and cool off equally quickly at night. However, coarser materials - bigger sand particles, gravel, and rocks - respond more slowly to the same daily cycle.

This means that when THEMIS views these late in the martian night, they appear warmer than the pools and patches of dust. In the image here, areas that are cold at night appear in blue tints, while the warmer areas show in yellows, oranges, and reds.

Location: 26.7N, 63.0E Released: 2006/02/07 Instrument: VIS Image Size: 37.7x34.2 km, 23.4x21.3mi, 2092x1907 pixels Resolution: 18m (59ft.)

Earth Science Literacy Initiative (ESLI)

PROJECT DESCRIPTION

The Earth Science Literacy Initiative (ESLI), funded by the National Science Foundation, aims to gather and codify the underlying understandings of Earth sciences into a succinct document that would have broad-reaching applications in both public and private arenas. It will establish the “Big Ideas” and supporting concepts that all Americans should know about Earth sciences. The resulting Earth Science Literacy framework will also become part of the foundation, along with similar documents from the Oceans, Atmospheres and Climate communities, of a larger geoscience Earth Systems Literacy effort.

The primary outcome of the Earth Science Literacy Initiative will be a community-based document that clearly and succinctly states the underlying principles and ideas of Earth science across a wide variety of research fields that are funded through the NSF-EAR program, including Geobiology and Low-Temperature Geochemistry, Geomorphology and Land-Use Dynamics, Geophysics, Hydrologic Sciences, Petrology and Geochemistry, Sedimentary Geology and Paleobiology, and Tectonics.

The Earth Science Literacy framework document of Big Ideas and supporting concepts will be a community effort representing the current state-of-the-art research in Earth sciences. It will be written, evaluated, shaped and revised by the top scientists working in Earth science. Because of its validity, authority and succinct format, the ESL framework will be influential in a wide variety of scientific, educational and political settings. Future governmental legislation will be guided by it, and future national and state educational standards will be based upon it.

Draft Document