Discoveries

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.

These clouds virtually disappear for months over much of Mars whenever the atmosphere contains warm dust.

Maximum atmospheric temperatures occur at the south pole at southern hemisphere solstice.

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.

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.

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.