Astronomical researchers have announced the discovery of 128 previously undetected moons orbiting Saturn, definitively establishing the planet as the solar system’s leader in satellite count. This significant finding elevates Saturn’s total moon tally to 274, a figure nearly double the combined number of moons orbiting all other planets.
The team responsible for this discovery, building upon earlier observations which identified 62 Saturnian moons using the Canada France Hawaii telescope, conducted further studies in 2023 after observing faint indications of additional satellites.
“Indeed, we found 128 new moons,” stated Dr. Edward Ashton, the lead researcher and postdoctoral fellow at the Institute for Astronomy and Astrophysics, Academia Sinica in Taiwan. “Based on our current projections, it is highly unlikely that Jupiter will ever surpass Saturn’s moon count.” As of February 5, 2024, Jupiter has 95 confirmed moons with established orbits.
The International Astronomical Union has formally recognized these newly discovered moons this week, assigning them temporary alphanumeric designations. Eventually, they will receive names derived from Gallic, Norse, and Canadian Inuit mythologies, in accordance with the established naming conventions for Saturn’s moons. The majority of these new moons fall within the Norse cluster, necessitating the exploration of lesser-known Viking deities for appropriate names.
“It may eventually be necessary to broaden the naming criteria slightly,” Ashton suggested.
These moons were identified using the “shift and stack” technique, which involves capturing sequential images to trace the moons’ movement across the sky and combining them to enhance their visibility.
All 128 of the newly discovered moons are classified as “irregular moons,” characterized by their potato-like shapes and small sizes, typically a few kilometers in diameter. The increasing number of these objects raises pertinent questions regarding the precise definition of a “moon.”
“I believe a formal definition for what constitutes a moon is necessary,” Ashton stated. However, he also acknowledged that the team may have reached the current limits of moon detection capabilities. “With current technology, I don’t believe we can significantly improve upon the detection capabilities already achieved for moons around Saturn, Uranus, and Neptune,” Ashton explained.
Detailed observations of these numerous small moons could provide scientists with valuable insights into a tumultuous period in the early solar system, characterized by planetary migration and frequent collisions. The clustering of these new moons suggests that they are remnants of larger objects that were shattered by collisions within the last 100 million years. These moons exhibit large, elliptical orbits that are inclined relative to the orbits of moons closer to the planet.
“They are likely all fragments of a smaller number of originally captured moons that were broken apart by violent collisions, either with other Saturnian moons or with passing comets,” stated Professor Brett Gladman, an astronomer at the University of British Columbia.
Understanding the dynamics of Saturn’s extensive moon system could also contribute to resolving questions about the origin of Saturn’s rings, which some scientists believe may be the result of a moon being disrupted by the planet’s gravitational forces.
In a separate development, the European Space Agency’s Hera spacecraft is conducting a Mars flyby, approaching within 300 kilometers of Deimos, Mars’s smallest and most distant moon. Deimos, which is approximately 7 miles across, is believed to be either a fragment from a major impact on Mars or a captured asteroid. Hera will also capture images of Mars’s larger moon, Phobos, before continuing its primary mission to survey Dimorphos, the asteroid that was deliberately impacted by NASA’s DART mission three years ago. Upon reaching Dimorphos, Hera will conduct a comprehensive post-impact survey to aid in the development of technologies for deflecting potentially hazardous asteroids.
