The competition between Jupiter and Saturn to hold the planet’s record with the greatest number of moons seems to have definitely turned in favor of the lord of the rings. Astronomes have in fact reported the discovery of 128 new moons around Saturn, bringing the total a 274 celestial bodies in orbit around the gassy giant. Saturn now has more moons than all the other planets of the combined solar system, with Jupiter now detached with only 95 moons. The discovery was made possible thanks to observations with long exposure times carried out by Canada-French-Hawaii telescopeon the sum of Mount Maunakea in Hawaii.
But do not think that these new moons are pleasantly spherical and as big as our moon. The new moons discovered all have irregular formsalmost potato, with a diameter between 2 and 4 km. As per tradition, the group of astronomers who discovered them will have the honor of name To each of them, probably taken from the Norse, Gallic or Canadian mythology, like other moons of this beautiful gassy giant.
How the new Lunes of Saturn were discovered
The team of astronomers led by Edward Ashton of the Sinica Academy of Taipei, Taiwan, discovered these 128 new moons using the Canada-French-Hawaii telescopea telescope of 4 meters in diameter which is located 4000 meters high on the top of Mount Maunakea, in Hawaii. The astronomers had to give a bottom to all the skills of this telescope in order to find new moons. The observations began before 2019: the more astronomers observed and superimposed the images to increase the signal, the more moons were identified. It started in 2019 with the discovery of 20 objects, followed by 62 in 2023, to end with the 128 confirmed by Minor Planet Center of NASA on 11 March of this year. Despite hours and hours of observations, due to the turbulent effect of the atmosphere most of these moons appears in the images as small blots blurred. Observations from the highest resolution will be needed to precision both the size and the shape.
The 128 new moons: how they are done and where they come from
The 128 new moons of Saturn have irregular formssimilar to a potato, with a diameter between 2 and 4 km. They follow large and elliptical orbitsOften very inclined with respect to the floor of the rings of Saturn. These characteristics make them part of the Norreno Group of Lune of Saturn, a group of moons who orbit retrograde direction, inclined corners and elliptical paths, outside the rings of Saturn. They are therefore very different from normal moons such as the Moon of the Earth, which follows a much less elliptical and inclined path.
Most of these moons orbit Saturn in retrograde motionthat is, in the opposite direction to the rotation of the planet. This is a clear indication of the fact that these moons they have not formed in the Saturnian systembut rather they were captured by the gravity of the planet. Originally, these moons were part of a small group of larger objects captured by Saturn. The latter subsequently met a series of hundreds of millions of millions of years ago who have fragmented them in small rocks such as those just discovered.
When it comes to moons: the minimum size limit
The new discoveries are not big and spherical like our natural satellite, but small and irregular. As the technological skills of telescopes are increasing, astronomers are discovering moons with an increasingly smaller diameter. At this point it becomes lawful to ask how small it can be a moon Before it’s simply a rock?
To this question, the astronomers of theInternational astronomical union (IAU) have been trying to respond for years, also because giving a name to each of them are becoming a problem that is not insignificant. The tendency of the IU seems to want to define a minimum limit in size so that an object can be considered a moon, which will probably be wandered Around the kilometer of diameter.
Despite this, research continues, also because mapping all the objects of the Solar System will prove to be very important in the future when, hopefully, humanity will become an interplanetary society interested in the extraction of resources from the asteroids and from the Solar System moons.
