A recent study has revealed that the slowing of Earth’s rotation over billions of years may have played a key role in the rise of oxygen in the planet’s early atmosphere. Around 2.4 billion years ago, Earth’s day was much shorter, and as the planet’s rotation gradually slowed, the lengthening of days allowed for extended periods of sunlight. This change likely boosted the activity of cyanobacteria, tiny organisms that produce oxygen through photosynthesis. As their photosynthetic activity increased, so did the oxygen levels in the atmosphere, sparking the Great Oxidation Event—a turning point that enabled the development of more complex life forms on Earth.
This discovery has significant implications for our understanding of Earth’s history and the conditions needed for life to thrive. It also offers valuable insights for the search for life beyond Earth. By identifying exoplanets with similar rotational patterns, scientists can evaluate their potential to support life. The study underscores the delicate balance of planetary processes and their impact on sustaining habitable environments, emphasizing how changes in Earth’s rotation helped create the oxygen-rich atmosphere we rely on today. More