Astrophysics Colloquium Imaging the Magnetosphere in Soft X-rays Presented by David Sibeck Space Weather Laboratory, NASA Goddard Space Flight Center Thursday, June 14, 2018 11:00 A.M. in 169-336 and on Webex Abstract Researchers at GSFC are developing wide field-of-view (FOV) telescopes to observe the soft X-rays emitted when high charge state solar wind ions like O7+ or C6+ exchange electrons with neutral atoms (e.g. at comets, in the helium focusing cone, and within the Earth's magnetosheath). When high charge state solar wind ions exchange charges with neutral atoms, the ions capture electrons in excited states and the neutral atoms are ionized. The ions then emit soft (0.1 to 1 keV) X-ray photons when the newly acquired electrons decay to quiet states. Narrow field-of-view soft X-ray telescopes have observed the line emissions generated by charge exchange coming from comets, Venus, Mars, the lunar exosphere, and the Earth's magnetosheath. Numerical simulations employing models for exospheric and plasma densities indicate that the locations of the bow shock, magnetopause, and cusps can be readily detected as sharp gradients in the images of line-of-sight emissions that wide FOV soft X-ray telescopes would produce. This presentation discusses the design of "lobster-eye" soft X-ray telescopes which rely on grazing incidence reflections, the scientific questions that they can be used to address at Earth, and prospects for future missions. JPL Contact: Bruce Tsurutani (4-7559)   Site Manager: Webmaster: CL 08-3220