The Hydrogen of the Virgo Cluster

About This Photograph

This is a color photograph of the Virgo Cluster of galaxies, combined with a long (over 75 hours) exposure through a hydrogen-alpha filter. This filter selectively lets through the wavelength of light associated with ionized hydrogen gas.

Between us and the cluster, there are known to be clouds of hydrogen within our own Milky Way, so what we see is the combination of these clouds plus any in the cluster itself. Though it is not possible to fully distinguish the two in this photo, some of the clouds are associated with the cluster galaxies. In particular, the clouds and filaments spanning M84, M86, and NGC 4435/8 (The Eyes), and those near M90, are clearly associated with these galaxies.

Click here for an annotated photograph.