Top TES Discoveries
1. TES discovered hematite in Meridiani Planum. Finding this iron-oxide mineral led NASA to send the Mars Exploration Rover Opportunity to Meridiani, a remarkable place with a water-rich history.
2. TES made the first global mineral maps of Mars and discovered that Martian igneous activity is roughly as diverse as Earth's. Martian volcanic minerals vary from basaltic to glassy dacite. Subtle variations in volcanic composition occur across the planet, with dacite and andesite flows in isolated areas.
3. TES discovered carbonate minerals that formed when water and the CO2 atmosphere react. The surprise was that the carbonates are in the dust, not in surface rocks, as many scientists had predicted.
4. TES discovered that unweathered volcanic minerals dominate the Martian dark regions. The lack of large-scale clay and carbonate mineral deposits means Mars has seen much less chemical weathering than Earth. In turn, this indicates Mars' geologic history has been mostly cold and dry.
5. TES discovered that jets of dusty gas produce dark markings on the south polar cap. During southern winter, carbon dioxide gas condenses onto the polar cap as a thin slab of transparent ice. When the Sun rises in spring, the ice sublimates from the bottom of the layer, while the growing gas pressure lifts the slab off the ground. Gas then breaks through the slab in places, erupting in jets that carry dust scavenged from under the slab.
6. TES provided the first systematic study of Martian weather. For three Mars years, TES operated much like a terrestrial weather satellite, making daily weather maps to track changes in atmospheric temperature, water-ice clouds, water vapor, and dust.
7. TES discovered large areas of exposed bedrock. While Mars is a dusty planet overall, TES mapped numerous places where nighttime ground temperatures indicate bare rock or hardened sediments essentially free of dust and sand.
8. TES monitored the growth and decay of the 2001 global dust storm. Each year regional dust storms occur during the southern hemisphere summer season. Clouds of dust also appear near the edge of the polar caps prior to the onset of a regional dust storm and over the polar cap during the storms.
9. TES discovered why the "Mountains of Mitchel" remain bright well into local spring. The "mountains," a misnomer that dates from the 19th century, are a heavily cratered area covered and uncovered each year by the southern seasonal polar cap. TES found the area remains cold and bright longer than other comparable areas because it is covered with unusually small grains of carbon-dioxide frost that persist longer.
10. TES mapped the atmosphere's global circulation for three Mars years. TES found that when the Sun stands over the Martian equator, the atmosphere develops a pattern with one northern hemisphere circulation cell and a similar southern one. At the solstices later in the year, however, the pattern shifts to a single larger cell in the warmer hemisphere that spreads across the equator. Also at the solstices, the large circulation cell spawns an eastward-flowing jet stream moving at more than 550 kilometers (340 miles) per hour.
11. TES showed that "White Rock" is neither white nor rock. The unusual feature in Pollack Crater, known for decades, has a spectrum that matches Martian dust, implying it is a stack of hardened dust layers.
12. TES traced the abrupt disappearance of the seasonal polar caps. As the Sun rises in local spring, most of the seasonal polar cap remains near the temperature of carbon-dioxide frost (-123° Celsius or -189° Fahrenheit). Then during about 20 days, its temperature climbs rapidly as the frost becomes patchy and disappears.
13. TES observed the atmosphere's thermal structure warms and cools according to season and distance from the Sun. Maximum atmospheric temperatures occur at the south pole at southern hemisphere solstice.
14. TES discovered that warm dust in the atmosphere prevents water-ice clouds. These clouds virtually disappear for months over much of Mars whenever the atmosphere contains warm dust.
15. TES discovered a new category of surface material. Before TES, scientists knew Mars has bright, fine-grain material (mostly dust) and dark, rocky material (essentially exposed bedrock). TES discovered a third type of surface material, medium in brightness and neither dusty nor rocky. The new surface material may consist of sediments that were once loose but have become cemented.