The Earth's Core Is Slowing Down and Now Spinning in the Opposite Direction: What Does This Mean?

This scientific discovery suggests that Earth may have once had multiple moons.

Astronomers have developed the most plausible scenario for a massive collision between Earth and another large planet, which may have led to the formation of the Moon—and possibly more than one. Have you ever wondered how the Moon was formed? The Moon and Earth are about the same age, approximately 4.5 billion years old, but there are several theories about how Earth's satellite came into being. One theory suggests they formed together from a protoplanetary cloud, while another posits that the Moon formed separately and was later captured by Earth's gravity. However, most scientists agree that the Moon was formed as a result of a violent collision between Earth and another large planet. Now, a new study suggests that additional moons may have been formed from that same collision.

After running simulations of the impact using state-of-the-art technology, scientists at the University of Nevada in the United States discovered that multiple celestial bodies could have emerged from the collision and existed for some time afterward. These bodies are known as circumbinary "moons." Unlike typical moons, which orbit a single planet, circumbinary moons orbit two celestial bodies—in this case, both Earth and the Moon.

According to researchers, when the Moon first formed, it was only about 5 percent farther from Earth than it is today. Over billions of years, tidal forces gradually pushed the Moon farther out to its current orbit. As the relationship between Earth and the Moon evolved, the circumbinary moons were eventually ejected from their orbits.

This discovery is significant not only for reconstructing the distant history of our planet but also for enhancing our understanding of similar celestial bodies being studied by astronomers. By examining this scenario, scientists can model various processes that may occur with planets in space and gain deeper insights into the mysteries of the Universe.

The first confirmed circumbinary planet was discovered a couple of decades ago, orbiting within the distant globular cluster M4, which contains a millisecond pulsar and a white dwarf. Since then, scientists have discovered many other circumbinary planets.