Pluto is fascinating to observe in its planetary system, particularly in light of the new moons discovered to exhibit strange orbiting patterns.
Pluto is one of the least study planets in and by itself, as well as in its planetary system. At an approximate distance of 3.7 billion miles from Earth, it is expected that when New Horizons swoops by the planet in mid-July, the dwarf planet and the observable surrounding system will reveal a little more of its secrets.
For now, scientists have found a new fascinating pattern of orbiting exhibited by Pluto’s moons that sheds some light on the mechanics of those exoplanets orbiting twin stars. At the same time, it adds to the confusing inconsistency in knowledge as to how these moons were formed. But theories are attempted.
Date from Hubble greatly aided the scientists team in observing the orbiting behaviour of the moons surrounding Pluto. Imagine something fully different to how we see our Moon in the sky, almost constantly on the same side due to its axis and planet orbit being completed at almost the same time.
Pluto’s moons are somethings else and quite a treat for the scientific community. So far, five moons have been discovered orbiting in Pluto’s planetary system. The smaller ones are Styx, Nix, Kerberos and Hydra. Pluto forms with its largest moon Charon a binary planet.
In this combination, Charon and Pluto orbit the same center of mass as they heavily influence each other gravitationally. The other four moons seem to be orbiting the same center rather than orbiting Pluto as such.
Styx, Hydra and Nix are bound by a three body resonance that usually causes them to act similar, and orbit circularly. Yet, interference from other bodies are injecting chaos in their pattern. Chaos is translated by a wobble in their orbiting pattern, much like that of a rugby ball. Specifically, it is Hydra and Nix that are rotating chaotically when the binary star’s torques are interfering.
The three smaller moons that are thrown into chaos yet are bound by three-body resonance are mirroring a similar pattern in the planetary system of Jupiter. Jupiter and the three moons Ganymede, Io and Europa are locked in a similar pattern of resonance.
As fascinating as it might be to observe new moons and their orbiting patterns, it is somewhat frustrating that due to the distance and the little data at hand very little is known about the formation of this particular binary planet system.
Scientist are left to speculate. Yet, it is possible that, just as it is believed it happened with the Earth’s Moon, Charon appeared when a larger cosmic object hit Pluto in the formation of the solar system. Due to gravitational pull, the smaller moons, possible debris, simply stabilized there.
There are consistent differences in the surfaces of the moons too, which further raises questions to how this binary planet satellite system could have come to form. For instance, Charon, Hydra and Nix present rather bright surfaces. Kerberos on the other hand is comparably darker.
The journal Nature features a full coverage of the results of the study on the moons of Pluto. Perhaps, with New Horizons’s input expected in mid-July, things will become even more interesting.
Image Source: techtimes.com