More orbital resonance systems of the planets and their moons in our solar system - this time the Pluto system with Charon, Hydra, Nix and Kerberos.
But the Pluto binary system also has a massive surprise, its smaller moons rotation are very chaotic with their spin all at different speeds and even one in a backward direction.
And why do Jupiter and Pluto moons not have a triple conjunction?
Yet, there’s a little problem in the system: the moons are also very close to one another, which is bad news for the long-term stability of their orbits.
Pluto and Charon are a binary system, which means that each circles around their common center of gravity. The four smaller moons in turn orbit around the pair and experience variable gravitational pulls as they approach and recede from Pluto or Charon. The result is a series of wiggles in the moons’ orbits. But since the moons are crowded so closely together, any disruption could potentially push them within range of one another’s gravity fields. Those tugs would further throw their orbital balance out of whack.
So how do moons that orbit with no room for wiggles keep their distance?
The solution appears to be a special three-body resonance. Hydra, Styx and Nix’s’ orbital periods are linked in ratios that prevent them from ever lining up in a row, which could permanently disrupt the system. Astronomers suspected for some time that resonances were at work, and Showalter and Hamilton have confirmed their existence with Hubble’s very precise measurements.
Resonance to the Rescue - Pluto’s Perplexing Moons | Sky and Telescope
Astronomers cannot directly measure the shape of Pluto’s moons, but they are able to measure their apparent brightness. If the moons were tidally locked with the host planet, they would notice an increase in brightness at two distinct points in the moon’s orbit. After analyzing the data, they found this wasn’t the case—the moons were not tidally locked and they were not spherical.
The data also showed that three of the four moons—Nix, Styx, and Hydra—were orbiting in sync, meaning there was a precise ratio to their orbital periods, 3:4:6. This provides stability and is the reason why such a tiny planet (like Pluto) can have so many moons.
Chaotic orbital interactions keep flipping Pluto’s moons | Ars Technica
Three of Pluto’s small moons are locked together in a mutual orbital dance, planetary scientists have found ... Now, researchers have found that the orbits of Styx, Nix and Hydra became gravitationally locked together at some point. “If you lived in the Pluto system and were sitting on Nix, you would see Hydra go around three times every time Styx goes around twice,” Showalter says. This pattern, known as a three-body resonance, remains stable over time. It is similar to the so-called Laplace resonance that links Jupiter's moons Io, Europa and Ganymede.
Pluto’s moons move in synchrony | Nature
But Pluto's moons chaotic rotations discovered
The orbits of Pluto's four smallest moons are even more chaotic than scientists had expected, according to new results from the New Horizons mission, which made a close flyby of Pluto in July. "The way I would describe this system is not just chaos, but pandemonium," Mark Showalter, a co-investigator on the New Horizons mission, said today (Nov. 9) during a news conference at the meeting of the Division for Planetary Sciences of the American Astronomical Society. "We honestly have not seen anything like this before, and we still don't know what to make of it."
The new results show that as the four moons orbit Pluto and its largest moon, Charon, some of them are spinning incredibly fast, one is spinning backward against its orbit and some are tilted on their sides ... Showalter said during the news conference that scientists expected to see "little wobbles" in the orbits of the four moons, but instead, they're seeing extremely rapid rotation. Hydra, the most distant of Pluto's moons, is spinning once every 10 hours during its 38-day cycle around Pluto, which means it spins 89 times every orbit ... In addition to these rapid rotations, Pluto's second-closest moon, Nix, is tilted on its axis by 132 degrees and is rotating backward.
Pandemonium! Motion of Pluto's Moons Perplexes Scientists | Space
Styx, Nix, and Hydra are thought to be in a 3-body orbital resonance with orbital periods in a ratio of 18:22:33. The ratios should be exact when orbital precession is taken into account. This means that in a recurring cycle there are 11 orbits of Styx for every 9 of Nix and 6 of Hydra, putting Nix and Hydra into a simple 2:3 resonance. The ratios of synodic periods are then such that there are 5 Styx–Hydra conjunctions and 3 Nix–Hydra conjunctions for every 2 conjunctions of Styx and Nix. As with the Laplace resonance of the Galilean satellites of Jupiter, triple conjunctions never occur.
Resonances - Moons of Pluto | Wikipedia
Pluto ‘Pandemonium’ explained in an Electric Universe
Could strange orbits or all the orbits of the planets and space bodies be explained by electromagnetic orbits in an Electric Universe?
At a recent NASA news conference, investigators on the New Horizons mission to the dwarf planet Pluto announced some astonishing findings. The moons in the Plutonian system behave in an extremely chaotic manner that planetary scientists admit is both unexpected and inexplicable. The term investigators have used to describe the moons’ motions is ‘pandemonium.’ In this Space News, Wal Thornhill explains the significance of these findings under the electric universe theory.
Pluto ‘Pandemonium’ | Thunderbolts