Scientists have revived the theory that short-period comets could have played a crucial role in filling Earth's oceans with water.

Comet 67P's water has the same molecular signature as Earth's oceans, suggesting it may have contributed to Earth's water supply.

A wave of comet and asteroid collisions with the solar system’s inner planets 4 billion years ago would have made this possible.,” a portion of the report read. Adding, tha

Researchers have found that water on Comet 67P/Churyumov–Gerasimenko has a similar molecular signature to the water in Earth's oceans. Contradicting some recent results, this finding reopens the case that Jupiter-family comets like 67P could have helped deliver water to Earth.