William E. Harris

TL;DR: In this article, the influence of orbital eccentricity on the dynamical evolution of star clusters was explored using N-body simulations and the authors found that the corresponding circular orbit which best describes the evolution of a cluster on an eccentric orbit is much less than its semi-major axis or time averaged galactocentric distance.

TL;DR: In this article, the authors used the Advanced Camera for Surveys and Wide Field Camera 3 cameras on board the Hubble Space Telescope to resolve stars in the halo of the nearest giant elliptical (gE) galaxy NGC 5128 out to a projected distance of 140 kpc (25 effective radii, R {sub eff}) along the major axis.

TL;DR: Les fonctions de luminosite de la sequence principale, construite a partir d'observations CCD, revelent une forte correlation entre la pente and la metallicite as mentioned in this paper.

TL;DR: In this paper, the first extensive cooling white dwarfs seen in a globular cluster was discovered in M4 (NGC 6121, C1620-264) using the Wide Field Planetary Camera 2 (WFPC2) on the Hubble Space Telescope.