  A disconcerting mismatch of thermal pressures for two media in contact with
each other, (1) the warm, Circum-heliospheric Interstellar Medium (CHISM) and
(2) the very hot material within a much larger region called the Local Bubble
(LB), has troubled astronomers for over two decades. A possible resolution of
this problem, at least in part, now seems possible. We now understand that
earlier estimates for the average electron density in the very hot LB plasma
were inflated by an unrecognized foreground contamination to the low energy
diffuse X-ray background measurements. This foreground illumination arises from
photons emitted by charge exchange reactions between solar wind ions and
neutral atoms from the interstellar medium that enter into the heliosphere.
However, with the resolution of this problem comes a new one. The high
ionization fraction of helium in the CHISM, relative to that of hydrogen, could
be understood in terms of the effects from a strong flux of EUV and X-ray
radiation coming from both the Local Bubble and a conductive interface around
the CHISM. A revision of this interpretation may now be in order, now that the
photoionization rate from radiation emitted by hot gas the Local Bubble is
lower than previously assumed.
