NASA craters on Mars show unexpected underground layers

NASA made five holes on Mars by crashing parts of its InSight lander into the surface. These impacts created craters that let scientists look at what lies just below the top layer of dust and rocks. The study of these spots showed a surprise about how the planet is built under the ground. Researchers found that the upper layer of Mars is different from what they thought before. This test gives experts new ways to learn about the history and makeup of the red planet.