The Mars Curiosity rover’s onboard mini-lab has helped confirm the existence of the largest organic molecules ever found on the Red Planet. The trio of long-chain compounds preserved in Martian soil are believed to be the remnants of prebiotic components required for life to develop on Earth.

Curiosity has previously discovered small organic molecules on Mars, but these recently found compounds are larger and would have require chemistry to reach a more advanced state to be produced. The finding is also good news for potential life hunters, as it shows that the indicators of life could still be around even after billions of years.

While the presence of these molecules is not proof of ancient life on Mars, scientists say it shows we could detect chemical signatures of past life, if it ever existed.