Scientists have discovered 2.7 billion-year-old volcanic rock containing tiny bubbles within them that will help researchers in unraveling the mystery of how life transformed on the Earth and will also give a better insight into the conditions on primordial Earth.
Analysis of the gas bubbles found in the volcanic rocks obtained from the ancient lava flows in western Australia reveals very astonishing facts. According to researchers, Earth back then had nearly half the air pressure when compared to the present situation and the atmosphere was very thin billions of years ago.
The study counters all the previous studies that suggest Earth had thicker atmosphere billions of years ago in order to compensate for a fainter sun. The sun formed nearly 4.5 billion years ago and Earth was very different at 2.7 billion years ago than what it is today. At that time, sun was 15 percent dimmer and eventually it brightened over a period of time.
Lead study author Sanjoy Som, CEO of Seattle-based Blue Marble Space, a nonprofit organization focusing on space science research, education and public outreach revealed that nearly 3 billion years ago, there was very less oxygen content in the atmosphere, days were shorter from today as Earth spun faster and only single cellular organisms existed on the Earth.
The study reveals some mind-boggling results. According to researchers, conditions at that time were very adverse for life forms but still they were able to thrive even in very harsh climatic conditions.
“Life doesn’t need conditions like modern Earth to survive and thrive. This is important in our quest for habitable environments in extra-solar planets,” Som added. “This study doesn’t yield direct knowledge about the air composition,” Som said. “Nonetheless, because most of the air pressure is nitrogen, and you needed greenhouse gases to compensate for a faint sun, methane — a powerful greenhouse gas — was a likely important constituent, as well as water vapour — another powerful greenhouse gas.”
Study authors used highly sensitive tools to analyse the age and size of the tiny air bubbles present in the molten rock found near the shores of Beasley River in Australia.
The study appeared in the journal Nature Geoscience.