Thomas H. Puzia

On the outskirts of the Virgo Cluster, where galaxies crowd together but haven't yet clumped into a dense mass, lies VCC 693. Outwardly, it's an unremarkable dwarf: a small cloud of stars and gas. But astronomers suspected that behind its calm appearance lurks a turbulent past.

Elliptical galaxies are quiet stellar metropolises in retirement. By all rights, their light should be calm, reddish, like a sunset. But their spectra scream otherwise: in the far ultraviolet, these old-timers blaze like holiday lights. For three decades, astronomers have puzzled over this 'ultraviolet upturn' (UV upturn).