The origins of life on Earth have been one of the great mysteries whose answers have been sought throughout history. For many years, scientists have looked to the stars, believing that the building blocks that started life on our planet came from an asteroid, comet or meteorite. But now some scientists say the true origins of life on Earth may have all come from here, on Earth.
A new paper shared in Science Advances, as well as a study published in The Conversation, examines the question of whether the origin of life on our planet may have actually been right here with us all this time. Researchers involved in this intriguing approach to finding out where life began on our planet say that life-enabling elements, called volatiles, may have existed on Earth from the beginning.
Several elements are considered volatile, including carbon, hydrogen, nitrogen and a group of elements that researchers call chalcogens. All of these volatile substances, including sulfur, selenium and tellurium, evaporate more easily than other elements, and understanding how these substances got to Earth could also help us understand the origin of life on Earth.
One of the most common theories, known as the late envelopment theory, says that the Earth initially consisted of materials low in volatile matter. But later, higher volatile concentrations began to appear as volatile-rich objects (meteors, comets, asteroids) crashed into the planet’s surface, allowing the planet to fully form.
But the problem with this theory is that these volatile-rich objects make up only about half a percent of the Earth’s mass. Therefore, most of these elements must have arrived on our planet some time after the formation of the Earth’s core. The new research says that these volatile substances have always been a part of the Earth and that the elements necessary for life have been here since the beginning, during the first formation of the planet.
The study also appears consistent with a study tracing the origin of water on Earth, according to the researchers. As scientists continue to investigate these and similar ideas, they may lead to a better understanding of the origin of life on Earth.