Observations of Elliptical Galaxies. I

Astronomy 626: Spring 1995

In the last 20 years our notions about E galaxies have changed radically; these galaxies are much more complicated than they first appeared.


Folklore & Mythology

Traditionally, elliptical galaxies were seen as rather simple systems. Their overall luminosity profiles were fit by the de Vaucouleurs (1948) law, while the cores seen in surface photometry of their central regions were frequently fit using King (1966) models. In form, these galaxies were often assumed to be oblate spheroids, flattened by rotation. The stars within them were viewed as belonging to a single, ancient population analogous to the bulge and halo populations of our galaxy; gas and dust were thought to be absent. Finally, elliptical galaxies were considered to be dynamically unevolved.

At one level or another, all of the above are incorrect.

Cores

Shapes

Kinematics

Shells & Other `Fine Structures'

Gas & Dust

Tidal Features

Next Time

Color & Line-Strength Gradients; Global Parameter Correlations; the Fundamental Plane of Elliptical Galaxies; Core Parameters & Galaxy Families.


References


Joshua E. Barnes (barnes@zeno.ifa.hawaii.edu)

Last modified: January 23, 1995