As we look around the universe, we are forever on the lookout for the cosmic missing links that will help us piece together how the structures in our universe transform over time. Locally, we see elder dwarf galaxies, devoid of any young stars. These systems are generally too small to see at great distances, and while we’ve speculated about their formation, catching a system in the act hasn’t been something we’ve been able to do… until maybe now.

Researchers using the Hubble Advanced Camera for Surveys (ACS) have identified five blue blobs of star formation that exist on the outskirts of the Virgo cluster in relative isolation. These locations were being looked at optically after radio data revealed these spots were rich in gas that they thought were associated with our galaxy.

Researchers weren’t expecting to find what could very well be baby dwarf galaxies, but, as researcher Michael Jones puts it: It’s a lesson in the unexpected. When you’re looking for things, you’re not necessarily going to find the thing you’re looking for, but you might find something else very interesting.

These systems are brilliantly blue and lack the characteristic red stars of older systems. They are also chemically diverse. This paints a picture of these gas blobs consisting of material stripped off older systems that are now forming brand new stars. This kind of gas stripping is the norm for systems falling into the Virgo Cluster, and now we know that gas can get recycled into something beautifully unexpected.

More Information

The University of Arizona press release

“Young, blue, and isolated stellar systems in the Virgo Cluster. II. A new class of stellar system,” Michael G. Jones et al., to be published in The Astrophysical Journal (preprint)