Charge exchange X-rays from the heliosheath

X‐rays are produced throughout the heliosphere as a consequence of charge transfer collisions between heavy solar wind ions and neutral atoms. After such a collision the solar wind ion is left in a highly excited state and emits extreme ultraviolet and soft X‐ray photons. In the outer heliosphere, solar wind charge exchange X‐ray emission is mainly due to charge exchange with neutral interstellar hydrogen. We have combined MHD simulations with a comprehensive charge exchange computation code. We trace the full evolution of solar wind ions along stream line in order to produce three‐dimensional emissivities and, subsequently, two‐dimensional X‐ray brightness and spectral maps of the heliosphere as would be observed from the outside. The model treats both the collisionally thin and the collisionally thick regimes. This model can be a diagnostic tool for studying stellar wind properties of nearby Sun‐like stars.