Astronomers from the Center for Astrophysics | Harvard & Smithsonian (CfA) have made a groundbreaking discovery, finding that super-Earths are common outside our solar system. A new study published in Science has revealed that these planets, which are bigger than Earth but smaller than Neptune, can be found in orbits farther out than Saturn.
The research team used the Korea Microlensing Telescope Network (KMTNet) to detect the microlensing effect, where light from distant objects is amplified by an intervening body like a planet. This technique allowed them to find planets at large distances from their host stars, including those between Earth and Saturn’s orbits.
According to Weicheng Zang, lead author of the study, “We found a ‘super-Earth’—meaning it’s bigger than our home planet but smaller than Neptune—in a place where only planets thousands or hundreds of times more massive than Earth were found before.” This discovery is significant because it shows that planetary systems can be different from our own.
The study also provides new insights into the populations of planets across the Milky Way. By measuring the masses of many planets relative to their host stars, the team has discovered that super-Earths are abundant in Jupiter-like orbits. In fact, there are at least as many super-Earths as Neptune-size planets.
This research has implications for our understanding of planetary formation and evolution. As Professor Shude Mao noted, “The current data provided a hint of how cold planets form.” With more data from the KMTNet survey, the team expects to constrain how these planets form and evolve even further.
The discovery of super-Earths in Jupiter-like orbits challenges our traditional view of planetary systems. As Jennifer Yee, co-author of the study, said, “This result suggests that in Jupiter-like orbits, most planetary systems may not mirror our solar system.” The researchers are now looking to determine how many super-Earths exist versus the number of Neptune-sized planets.
The study was a collaborative effort between CfA and other institutions, including KASA, OGLE, and MOA survey groups. It provides new evidence for the existence of super-Earths beyond our solar system and highlights the importance of continued exploration and research in this field.
Source: https://phys.org/news/2025-04-super-earths-common-solar.html