A new study by scientists from Rutgers University (USA) suggests that water on our planet emerged later in Earth's formation than previously thought. This discovery reshapes our understanding of when conditions suitable for life may have first appeared. The research was published in the journal Geochimica et Cosmochimica Acta (GCA).

When Did Conditions for Life Appear on Earth?

For life to originate, three key elements are necessary:

  • Water
  • Energy
  • Organic compounds (CHNOPS — carbon, hydrogen, nitrogen, oxygen, phosphorus, and sulfur)

Understanding when water appeared helps determine when the first living organisms could have emerged.

How Did Scientists Determine When Water Appeared?

The research team analyzed the isotopic composition of molybdenum in Earth's rocks and meteorites. They compared meteorites from the inner (dry) and outer (wet) regions of the Solar System with rock samples from different parts of Earth.

The results showed that Earth's rock chemistry is more similar to meteorites from the inner Solar System, which are considered drier. This suggests that a significant amount of water could not have been delivered to Earth during the Moon’s formation, around 4.5 billion years ago.

Late Accretion and Water Delivery

Researchers concluded that water arrived on Earth later, during the process of late accretion, when the planet accumulated its final 10–20% of mass.

"Our results show that conditions for life formed later than we previously thought," said lead author of the study, Catherine Bermingham.

This discovery changes our understanding of Earth’s early history and may influence the search for life on other planets. If water appeared on Earth later, similar processes may also be occurring on exoplanets that we are studying today.