The European Space Agency’s Euclid mission, launched in July 2023, is making strides in understanding why galaxies appear in different shapes. This mission aims to explore how galaxies and their supermassive black holes grow together over time. After just one year, Euclid has already observed about 1.2 million galaxies. Before the mission wraps up in six years, it plans to study tens of millions of galaxies, providing a wealth of data for astronomers.
Maximilian Fabricius, a scientist at the Max Planck Institute, emphasizes the importance of Euclid’s ability to map the entire extragalactic sky. He shared that, for the first time, researchers can examine how the shapes and structures of galaxies connect to their formation histories on a cosmic scale.
The variety of galaxy shapes, from spirals like the Milky Way to elliptical ones such as Messier 87, results from their evolutionary paths. Using Euclid’s data, scientists created a “galactic tuning fork,” illustrating how galaxies transition from blue star-forming types to larger, elliptical galaxies as they age and exhaust their star-forming materials.
Euclid’s team has also spotted potential “secondary nuclei” in some galaxies. These are smaller black holes that might merge with larger ones during galactic collisions, which is a key phase in the merging process. Such mergers can ultimately lead to the creation of even bigger supermassive black holes, significantly altering the galaxies that host them.
According to Fabricius, “The largest black holes are found in giant elliptical galaxies and mainly grow through merging.” As galaxies collide, their black holes sway around each other, producing gravitational waves that carry energy away, causing them to spiral closer until they merge. This merging phase is crucial for understanding both black hole and galaxy growth.
Interestingly, Euclid’s findings challenge previous assumptions. Researchers have discovered that the most common type of galaxy isn’t the grand spiral, but rather faint dwarf galaxies. So far, Euclid has identified 2,674 dwarf galaxies; their existence suggests they may be the building blocks of larger galaxies, such as the Milky Way.
With only 0.5% of its data released, Euclid has already changed how scientists view galactic structures. This mission promises to reshape our understanding of galaxies and how they evolve, creating a deeper insight into the universe.
The implications of these discoveries extend beyond pure science. Popular science forums and social media have buzzed with excitement around Euclid’s findings, highlighting a growing public interest in cosmic exploration. As researchers continue to analyze the data, we can expect even more revelations about our universe.
For those intrigued by the cosmos, the European Space Agency’s updates will keep you informed as this exciting mission unfolds.
