For the first time, high-resolution images show the three-dimensional structure of massive ice deposits on Mars.
According to an in-depth analysis led by the U.S. Geological Survey, the images reveal never-before-observed details about the ice sheets, including that some begin just a few feet below the Martian surface and extend to depths greater than 300 feet.
The study, which used data from NASA's Mars Reconnaissance Orbiter and which was published in the journal Science, shows there is low rock and dust content in the exposed ice.
Scientists say this means that relatively pure water ice, capped by only a thin layer of ice-cemented rock and dust, may be readily accessible to future exploration missions.
Researchers say there is ice under roughly a third of the Martian surface, which records the recent geologic history of Mars.
Although water ice deposits are known to exist from previous Mars missions, this new study analyzed the vertical structure and thickness of ice sheets using high-resolution imagery and topography from the HiRISE instrument on NASA’s Mars Reconnaissance Orbiter.
The study examined north and south pole-facing erosional slopes, known as scarps, in eight locations around Mars, all in the mid-latitudes.
Similar to ice cores recovered from the Earth’s surface, these ice sheets may preserve a record of ice deposition and past climate on Mars.
Images of the erosional scarps reveal geologic features of the ice, such as banded patterns and color variations due to layering.
Such details suggest ice layers with different proportions of ice and dust that could have formed under varying climate conditions.