X-Ray Emissions from Charge Exchange in the Heliosphere

Abstract

X‐Rays are generated throughout the heliosphere and the terrestrial magnetosheath as a consequence of charge transfer between heavy solar wind ions and interstellar and geocoronal neutrals. These X‐ray intensities, as observed from Earth, depend on look direction and season. Due to rapid variation in geocoronal X‐ray emissions in response to time variations in the solar wind flux, it might very well be possible to observe Earth’s magnetosheath from an observation point outside the geocorona. In previous papers we have shown that there is significant correlation between “long term enhancements” in the soft X‐ray background measured by the Rontgen Satellite (ROSAT), and that roughly 25–50% of the soft X‐ray background maps are of heliospheric origin. In this paper we present a preliminary simulated soft X‐ray image of the heliosphere as would be seen by an external observer.