Life is not always easy for astrophysicists: just when they've discovered another aspect of the movement patterns in our solar system, two of the moons of Neptune come to mess things up.
The two eligible moons are Naiad and Thalassa, both about 100 kilometers or 62 miles wide, and running around their planet in a race called "Dance of Avoidance" by NASA researchers.
Compared to Thalassa, Naiad's orbit is tilted at about five degrees – he spends half of his time over Thalassa and half under Thalassa in an orbit comparable to nothing else.
"We call this repetitive pattern a resonance," says physicist Marina Brozovic of the NASA Jet Propulsion Laboratory. "There are many different types of dances that planets, moons and asteroids can follow, but this has never been seen before."
The orbits of the two small moons are only about 1
If you were stationed on Thalassa, you would see Naiad go over and under in a pattern that would repeat every four loops. as Naiad repeatedly outscored his neighbor. According to the researchers, these maneuvers keep the orbits stable.
The team used data collected from Earth Telescopes, Voyager 2 and the Hubble Space Telescope between 1981 and 2016 to determine how Naiad and Thalassa bypass the ice giant they call home.
These moons are two of 14 satellites confirmed for Neptune and two of the seven so-called Inner Moons, a very dense system interwoven with weak rings.
According to the researchers, the capture of the great Neptune's Moon Triton could explain the origins of Naiad and Thalassa and how they orbited their planet in such unusual ways.
The inner moons may represent Triton's remains, the team suspects, with Naiad finally entering his oblique orbit through an interaction with another of those neighbors.
In addition to depicting the orbits of Naiad and Thalassa, the new study also took initial steps to determine the composition of the inner moons of Neptune, which seem to be composed of something similar to water ice.
"We are always excited to find these interdependence between moons," says planetary astronomer Mark Showalter of the SETI Institute.
"Naiad and Thalassa are probably interconnected in this relationship configuration for a very long time because it makes their orbits more stable." They preserve peace by never getting too close. "
The research was conducted in Icarus published.