A recent study by American scientists reveals that Earth-like planets currently account for only 8% of the total planets suitable for life throughout the universe.
In the future, billions of Earth-like planets will form. Image: NASA/ESA/G. Bacon.
This analysis is based on data from NASA’s Hubble Space Telescope and the Kepler space observatory, indicating that the majority of Earth-like planets have yet to form. Earth-like planets are defined as rocky planets orbiting their parent stars in regions conducive to life, where liquid water can exist.
The study does not aim to prove the rarity of Earth-like planets, as there are billions of planets outside our solar system located in life-friendly zones. Instead, it offers insights into the formation of stars and planets in the future. Galaxies in the universe continue to evolve, generating stars and planets over an extended period.
While tracking the evolution of ancient galaxies, researchers at the Space Telescope Science Institute in Baltimore, USA, observed that despite the slow progress of star formation, the available gas resources to create stars are more abundant than during the early universe’s formation. According to the research team’s calculations, the last star in the universe will shine for 100 quintillion years, a duration sufficient for billions of Earth-like planets to emerge.
Currently, Earth-like planets make up only 8% of the total number of life-sustaining planets that will form throughout the universe’s existence.
“Our main motivation is to understand Earth’s place relative to the rest of the universe. Compared to all the planets that will form in the universe, Earth formed early,” explained Peter Behroozi, a planetary scientist at the Space Telescope Science Institute and the lead researcher.
“There is still enough material left after the universe’s big bang for many more planets to be born in the future, both within our galaxy and beyond,” added Molly Peeples, co-author of the study.
Behroozi and Peeples suggest that future planets will undoubtedly emerge in massive galaxy clusters and dwarf galaxies, where reserves of unused gas remain.