2. Learn how we study geology on Earth and other planets
On Earth, geologists have the luxury of making observations and collecting rock samples in person. To study rocks and soil on other planets, like Mars, we have to rely on spacecraft that can use their cameras and tools to act as our eyes and hands.
For example, Mars rovers like Curiosity and Perseverance use cameras to send detailed pictures of the Martian surface back to us on Earth so we can explore from a distance. We then compare the images to known substances on Earth to better understand and theorize about how the Martian rocks, soil, and minerals formed.
About the image: The image above, captured by NASA's Curiosity rover on Mars, shows an outcropping – an area where ancient bedrock underneath the surface is exposed. Outcroppings on Earth are known to form as a result of running water and create gravel that's a similar size and shape. By comparing this image of Mars to similar features on Earth, geologists have been able to theorize that Mars might have also once had running water.
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