Testing a Fast Dynamical Indicator: The MEGNO

TL;DR

This paper evaluates the effectiveness of the MEGNO indicator in analyzing non-linear dynamical systems, demonstrating its reliability through numerical tests on galactic orbits and comparing it with traditional methods.

Contribution

It provides a detailed numerical and statistical assessment of MEGNO's performance in galactic dynamics, highlighting its advantages over existing indicators.

Findings

MEGNO effectively distinguishes between regular and chaotic orbits.

It correlates well with Finite Time Lyapunov Characteristic Numbers.

The study confirms MEGNO's speed and reliability in complex dynamical systems.

Abstract

To investigate non-linear dynamical systems, like for instance artificial satellites, Solar System, exoplanets or galactic models, it is necessary to have at hand several tools, such as a reliable dynamical indicator. The aim of the present work is to test a relatively new fast indicator, the Mean Exponential Growth factor of Nearby Orbits (MEGNO), since it is becoming a widespread technique for the study of Hamiltonian systems, particularly in the field of dynamical astronomy and astrodynamics, as well as molecular dynamics. In order to perform this test we make a detailed numerical and statistical study of a sample of orbits in a triaxial galactic system, whose dynamics was investigated by means of the computation of the Finite Time Lyapunov Characteristic Numbers (FT-LCNs) by other authors.