Mars, the red planet in the Solar System, has undergone many climate changes over the past billions of years. From a planet that may have once had a thick atmosphere and liquid water flowing on its surface, Mars is now a cold, arid world with a thin atmosphere and harsh climate. NASA’s two major missions, Curiosity and Perseverance, have played important roles in discovering and deciphering these climate changes. Data collected from the surface of Mars has helped scientists better understand the planet’s climate history, from its watery period to its current cold and arid period.
Curiosity, operating since 2012 at Gale crater, and Perseverance, landing in 2021 at Jezero crater, are both equipped with advanced scientific instruments to study the surface, geology and climate of Mars. The findings from these two missions not only provide greater insight into Mars’ past climate but also open up questions about the existence of water and the possibility that the planet once supported life.
Ancient Climate on Mars: The Age of Liquid Water
One of the most important findings from both Curiosity and Perseverance is evidence that Mars once had a warmer and wetter climate that allowed liquid water to exist on the surface. Curiosity has found signs of ancient rivers and lakes in Gale Crater, suggesting the area was once a large lake bed filled with water. Minerals such as clay and hematite found here only formed in wet environments, reinforcing evidence of the existence of liquid water during the Noachian period, about 3.5 billion years ago.
The Perseverance, on a mission to explore Jezero crater, also discovered evidence of an ancient river system that once flowed into Jezero Lake. Sediment layers found in the river delta at Jezero suggest that the water was present for a long period of time, allowing organic compounds and potential biological markers to form. This wet climate may have persisted for millions of years before Mars gradually lost its thick atmosphere and became as dry as it is today.
The Role of the Atmosphere and Solar Wind in Climate Change
Data from both probes shows that atmospheric loss was one of the key factors that led to Mars becoming arid and cold. Mars does not have a strong magnetic field like Earth to protect the atmosphere from the solar wind, causing the atmosphere to gradually be blown into space over billions of years. Curiosity has discovered that Mars’ current atmospheric pressure is only about 1% of Earth’s, which is not enough to keep liquid water on the surface.
Perseverance, through studying sediment layers and geological surfaces, also provides more information about how the Martian atmosphere changed over time. Data from rock and soil samples collected shows that Mars has experienced cycles of climate change, from wet periods to dry and cold periods. These findings help strengthen the theory that Mars once had an atmosphere thick enough to maintain liquid water and potentially support life.
Mars’ Current Climate: Cold and Harsh
Currently, Mars is an extremely cold planet, with average temperatures around -80 degrees F (-60 degrees C), and can drop much lower at night or in the polar regions. . The thin atmosphere of mostly CO2 is not enough to retain heat, making it impossible for Mars to maintain liquid water on the surface in its current climate. Global sandstorms, as documented by Curiosity and Perseverance, are also a prominent feature of the Martian climate. These storms can last for weeks, even months, covering the entire planet and transforming the surface.
Although liquid water no longer exists on the surface, both Curiosity and Perseverance have found evidence of subsurface ice and groundwater, especially in the polar regions and lowlands. This opens up the possibility that beneath the arid surface, Mars still has areas with water, which could be important for supporting microbial life if it exists.
Learn About Past Climates Through Sedimentary Layers
The ancient rocks and sediments at Gale and Jezero craters are natural “records” of Mars’ climate history. Curiosity has collected samples from sediments at Gale crater, helping scientists better understand how Mars’ climate has changed over billions of years. The rock layers here contain information about past humid climates and the transition to current arid environments.
Perseverance, which explores the sediments at Jezero Crater, has discovered that the rocks can provide clues about when liquid water existed and the climatic conditions that supported it. life. Samples collected by Perseverance will be archived for future return to Earth, providing the opportunity to further analyze Mars’ climate and past life-support potential.
Climate of Mars
The Curiosity and Perseverance missions have provided valuable data that help us better understand the history of Mars’ climate, from warm and wet periods to the current arid and cold period. Findings from these missions suggest that Mars had favorable conditions for liquid water to exist and potentially support microbial life in the past. Although Mars’ current climate is harsh, evidence of underground water and subsurface ice still holds out hope for the possibility of life, at least in microbial form. In the future, subsequent missions will continue to explore and further study the climate history of Mars, thereby helping us better understand the possibility of human settlement on the red planet.
