ESA | HEIC | 2014 July 22
Astronomers using the NASA/ESA Hubble Space Telescope have probed the extreme outskirts of the stunning elliptical galaxy Centaurus A. The galaxy’s halo of stars has been found to extend much further from the galaxy’s centre than expected and the stars within this halo seem to be surprisingly rich in heavy elements. This is the most remote portion of an elliptical galaxy ever to have been explored.Image credit: ESA/Hubble, NASA, Digitized Sky Survey, MPG/ESO
Acknowledgement: Davide de Martin
There is more to a galaxy than first meets the eye. Extending far beyond the bright glow of a galaxy's centre, the swirling spiral arms, or the elliptical fuzz, is an extra component: a dim halo of stars sprawling into space.
These expansive haloes are important components of a galaxy. The halo of our own galaxy, the Milky Way, preserves signatures of both its formation and evolution. Yet, we know very little about the haloes of galaxies beyond our own as their faint and spread-out nature makes exploring them more difficult. Astronomers have so far managed to detect very few starry haloes around other galaxies. ...
Tracing the outer halo in a giant elliptical to 25 Reff - M. Rejkuba et al
- Astrophysical Journal Letters 791(1) L2 (2014 Aug 10) DOI: 10.1088/2041-8205/791/1/L2
arXiv.org > astro-ph > arXiv:1406.4627 > 18 Jun 2014