How did life begin on Earth? While scientists have theories, they don’t yet fully understand the precise chemical steps that led to biology, or when the first primitive life forms appeared.
But what if Earth’s life did not originate here, instead arriving on meteorites from Mars? It’s not the most favoured theory for life’s origins, but it remains an intriguing hypothesis. Here, we’ll examine the evidence for and against.
Timing is a key factor. Mars formed around 4.6 billion years ago, while Earth is slightly younger at 4.54 billion years old. The surfaces of both planets were initially molten, before gradually cooling and hardening.