Fig. 4: All-sky maps of Galactic gas tracers used in this study.
From: A nearby dark molecular cloud in the Local Bubble revealed via H2 fluorescence
Top row: FIMS/SPEAR O vi data, modified from ref. 52. The Eos cloud shows a distinctive absorption of hot gas traced by O vi. Second row: CO data from ref. 6 highlighting the Eos cloud. The small CO-bright region within the on-sky cloud boundary is shown by the white arrow. Bottom two rows: ROSAT 0.25-keV (third row) and 1-keV (bottom row) all-sky maps from ref. 34. The Eos cloud shows a prominent outline absorbing the soft-X-ray flux and creating a bright X-ray halo towards lower Galactic longitude. The interaction region provides a nearby example of a hot–cold gas interface. Magenta contours are overlaid, showing the location of strong H2 fluorescence from Fig. 1. The Eos cloud is outlined and a cut-out zooming in on the region is provided.
