The Curiosity rover, which landed on Mars in 2012, examined various aspects of the Gale Crater on Mars to learn more about this transition from warm and wet to dry and very cold.
The latest study, derived from data captured with one of the rover’s instruments, suggests that Mars actually switched between wetter and drier periods before it completely lost its surface water about three billion years ago.
Since 2014, curiosity has been rising steadily for the 3 mile high Mount Sharp, which is located in the center of the Gale Crater.
An instrument called the ChemCam sits on the rover’s mast and contains a high-resolution camera and laser that can vaporize stones to help the rover analyze its chemical makeup. ChemCam has an infrared colored laser that can heat boulders to 18,000 degrees Fahrenheit. This vaporizes the rock and creates plasma, essentially allowing scientists to look into the minerals and chemicals in the rock and look back at the geological history of the planet.
The camera on ChemCam was used to capture observations of Mount Sharp’s terrain, revealing slices of Martian past as the rock changes.
A Mars history lesson
Mount Sharp is a fascinating feature on Mars as it is one of the best ways the red planet records the history of its climate, water, and sediment.
“A primary goal of the Curiosity mission was to investigate the transition between the habitable environment of the past and the dry and cold climate of Mars. These rock layers recorded this change in great detail,” said Roger Wiens, co-researcher of the study author of the paper and ChemCam team scientists at Los Alamos National Laboratory in a statement.
The study was published in the journal Geology last week.
Orbiters around Mars previously recorded information about the minerals in the slopes of Mount Sharp. Curiosity’s data have provided even more detailed observations of the sedimentary rock layers, revealing dry and wet periods in the planet’s past.
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Curiosity recognizes great changes in shifts
When Curiosity climbed Mount Sharp, the plains changed dramatically.
The base of Mount Sharp is made of clay deposited by the lake that once filled the crater. Above it are layers of sandstone that still contain evidence of how they were formed by wind-shaped dunes in drier times. Layers above show more debris from the flood plain, indicating when the wet conditions returned to Mars.
Curiosity’s observations show that these changes between wet and dry epochs were large-scale events that alternated until the planet became permanently dry. Mount Sharp’s climate record has allowed Curiosity to focus on a period of 2.9 to 3.7 billion years.
As the rover continues its mission, Curiosity will continue to ascend the foothills of Mount Sharp, using its drill to further explore the types of rock and their revelations. This could provide more information about the cause of such drastic climatic fluctuations.