The Early Sun's Rings Stopped Our Planet from Becoming a 'Super-Earth'

The enormous Saturn-like rings were made of gas and dust.
Chris Young

The sun was once surrounded by rings of gas and dust similar to those orbiting Saturn, a new study published in the journal Nature Astronomy reveals.

These rings played a vital role in the formation of our solar system and in the size and habitability of Earth.

The early sun's dust and gas rings may have stopped our planet from becoming a "super-Earth," according to the Rice University astrophysicists behind the new paper. "In the solar system, something happened to prevent the Earth from growing to become a much larger type of terrestrial planet called a super-Earth," Rice University astrophysicist André Izidoro, said in a press statement.

Super-Earths are enormous rocky planets that have been observed around approximately 30 percent of sun-like stars in the Milky Way. Using advanced computer modeling to simulate the formation of our solar system, the Rice University scientists observed that the early sun likely produced three bands of high pressure, called "pressure bumps", which have been observed around far-off stars. These discs likely impeded the necessary material from reaching Earth that would make it a "super-Earth", the scientists argued.

Why we don't have a super-Earth in our solar system

"If super-Earths are super-common, why don’t we have one in the solar system?" Izidoro said. "We propose that pressure bumps produced disconnected reservoirs of disk material in the inner and outer solar system and regulated how much material was available to grow planets in the inner solar system."

In their simulations, Izidro said the timing of pressure bump formation proved to be crucial in the formation of super-Earths. "By the time the pressure bump formed in [some] cases, a lot of mass had already invaded the inner system and was available to make super-Earths," he said. "So the time when this middle pressure bump formed might be a key aspect of the solar system."

Most Popular

The researchers' modeling provides new insight into the very early formation of our solar system, and the model accurately reproduced known features of our solar system that were missed by other previous models, the researchers said. Soon, new data from the recently-launched James Webb Space Telescope will provide further insight into the early composition of solar systems and will allow the scientific community to compare such models to distant approximations of the real thing.