The Eridanus superbubble in its multiwavelength glory

The Orion-Eridanus Superbubble is the Rosetta Stone of superbubbles. It is in a middle evolutionary stage, having originated long ago but still being energized by massive stellar winds and supernovae; this means it exhibits the full range of astrophysical processes that occur whenever all of the interstellar gas phases lie in close proximity. It is nearby, so only modest angular resolution is required and, more importantly, it is the only object along the line of sight so its maps can be interpreted unambiguously. We bring together the full range of available data to show that the multiwavelength whole is far more than the sum of its parts. For example, we see the hot interior gas leaking to the outside from a hole in the rear wall of the shell.