Dark comets have long been thought to be a single type of celestial body, but new discoveries reveal that there are at least two distinct populations based on their orbits and sizes.
In 2023, the first dark comet was discovered, followed by six more. Since then, an international team of astronomers has identified seven additional dark comets, doubling the total known to 14.
The discovery of these enigmatic rocks could provide insight into how Earth became habitable for life. Researchers believe that dark cometary material may have delivered vital volatiles and organics necessary for life’s development.
One key characteristic of dark comets is their acceleration, which cannot be explained by gravity or the Yarkovsky effect. This acceleration suggests that these objects are actively releasing volatile materials from their surfaces, providing a thrust that alters their motion.
By analyzing reflectivity and orbits, scientists have identified two distinct types of dark comets. One population inhabits the inner Solar System, with smaller sizes and circular orbits, while the other is more chaotic, with highly elliptical orbits that take them nearly as far as Jupiter or closer to Mercury.
The discovery of these dark comets has significant implications for our understanding of the origin of life on Earth. As researchers continue to study these enigmatic rocks, they hope to answer questions about their composition, origins, and potential role in delivering vital materials to our planet.
Source: https://www.sciencealert.com/dark-comets-come-in-different-varieties-and-it-could-have-implications-for-life-on-earth