Planetary Nebulae as Tracers of Intergalactic Stars

Planetary nebulae can be detected far into the halos of elliptical galaxies. In fact, in the Virgo Cluster, PN can be found so far out that they are not in any galaxy at all! There are literally tens of thousands of detectable planetary nebulae in the intergalactic space of Virgo. All one needs to do is image the cluster through a narrow-band [O III] 5007 filter using a 4-m class telescope.

Intergalactic planetary nebulae can provide an enormous amount of information about a cluster's evolutionary state and dark matter content. Observations suggest that about 15% of the stellar mass of Virgo lies in intergalactic space, and these nomadic stars are non-virialized, non-uniformly distributed, and have moderate age and metallicity.

For further information check out our

Publications on the subject.

Web page by Robin Ciardullo ( rbc@astro.psu.edu )
Department of Astronomy and Astrophysics
Penn State University