Dark No More: The Low-luminosity Stellar Counterpart of a Dark Cloud in the Virgo Cluster
Abstract
We have discovered the stellar counterpart to the ALFALFA Virgo 7 cloud complex, which has been thought to be optically dark and nearly star-free since its discovery in 2007. This ∼190 kpc long chain of enormous atomic gas clouds (M H I ∼ 109 M ⊙) is embedded in the hot intracluster medium of the Virgo galaxy cluster but is isolated from any galaxy. Its faint, blue stellar counterpart, BC6, was identified in a visual search of archival optical and UV imaging. Follow-up observations with the Green Bank Telescope, Hobby–Eberly Telescope, and Hubble Space Telescope demonstrate that this faint counterpart is at the same velocity as the atomic gas, actively forming stars, and metal-rich (12 + (O/H) = 8.58 ± 0.25). We estimate its stellar mass to be only
- Publication:
-
The Astrophysical Journal
- Pub Date:
- May 2024
- DOI:
- 10.3847/2041-8213/ad3ef5
- arXiv:
- arXiv:2402.14909
- Bibcode:
- 2024ApJ...966L..15J
- Keywords:
-
- H I line emission;
- Virgo Cluster;
- Galaxy interactions;
- Ram pressure stripped tails;
- Star forming regions;
- 690;
- 1772;
- 600;
- 2126;
- 1565;
- Astrophysics - Astrophysics of Galaxies
- E-Print:
- Accepted to ApJL