Hubble, Euclid & Subaru uncover dark galaxy

Astronomers have uncovered a dark galaxy using three powerful observatories: the Hubble Space Telescope, Euclid space observatory, and the ground-based Subaru Telescope in Hawaii.

Hubble’s high-resolution imaging revealed a close collection of four globular clusters in the Perseus galaxy cluster, 300 million light-years away. Follow-up studies using Hubble, Euclid, and Subaru data then revealed a faint, diffuse glow surrounding the star clusters – strong evidence of an underlying galaxy, dubbed CDG-2. The Euclid data clearly confirms the presence of the extremely faint, diffuse light of CDG-2, revealing the galaxy behind the globular clusters for the first time.

This galaxy belongs in the rare class of galaxies which are nearly invisible – low-surface-brightness galaxies, which are dominated by dark matter and containing only a sparse scattering of faint stars. It may be among the most heavily dark matter-dominated galaxies ever discovered. Most of the matter in the Universe is dark, and does not reflect, emit, or absorb light, but reveals its prescence through gravitational influence on luminous matter such as stars.

The science paper detailing this finding was published in The Astrophysical Journal Letters. For more details, click here.