For centuries, Martian rocks have bombarded Earth, hurtling through space after being expelled from their home planet due to violent impacts or volcanic processes. However, as we gather these minuscule samples, scientists have made an intriguing discovery: the age of these Martian rocks does not align with the overall age of Mars. They are significantly younger.
Mars is incredibly ancient. Scientists estimate that the planet finished forming around 4.56 billion years ago, approximately 90 million years prior to Earth. Moreover, evidence indicates that most of the Martian surface is old. So, why do chunks of Martian rock exhibit such a youthful age?
They claim that the likely explanation lies in the continual bombardment of the Martian surface by meteorites and asteroids. With roughly 200 meteorite impacts creating 4-meter craters annually, the Martian surface is constantly ejecting more rock into space, some of which reaches Earth. The discrepancy in the ages of Martian rocks occurs because the younger rock is replacing the older rock as it is expelled from the planet.
This implies that the younger rock from beneath the surface, which is still being replenished by volcanic activity, eventually becomes exposed to the surface and becomes the ejecta that meteorites propel into space. According to a group of scientists in a paper published in Earth and Planetary Science Letters, this could shed light on why the Martian rocks found on Earth appear so youthful.
Understanding how Mars is evolving, both internally and externally, is crucial as NASA and others prepare for the first manned missions to Mars. Additionally, scientists are continually seeking new ways to comprehend the formation of the planets in our solar system and how that knowledge can further our understanding of the universe’s evolution as a whole.
