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arXiv · astro-ph/9601091

Chaos and the Shapes of Elliptical Galaxies

David Merritt
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Abstract

Hubble Space Telescope (HST) observations reveal that the density of stars in most elliptical galaxies rises toward the center in a power-law cusp. Many of these galaxies also contain central dark objects,possibly supermassive black holes. The gravitational force from a steep cusp or black hole will destroy most of the box orbits that constitute the ``backbone'' of a triaxial stellar system. Detailed modelling demonstrates that the resulting chaos can preclude a self-consistent, strongly triaxial equilibrium. Most elliptical galaxies may therefore be nearly axisymmetric, either oblate or prolate.

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David Merritt. 1996-01-17. Chaos and the Shapes of Elliptical Galaxies. https://doi.org/10.1126/science.271.5247.337

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