LEXI: The Lunar Environment heliospheric X-ray Imager

LEXI is a wide-field X-ray imager that will land on the Moon in 2024 to observe observe soft X-rays generated by charge exchange between high charge state solar wind ions and exospheric neutrals within the Earth’s dayside magnetosheath over the course of eight days. It employs bare-glass slumped micropore (lobster-eye) optics and an MCP detector. The LEXI optic was characterized at PANTER, where the effective area was measured using a continuum source in order to characterize the effective area curve at moderate energy resolution over the 0.2-4.0 keV range. The performance of the entire instrument was characterized at the MSFC Stray Light Facility. We will also describe the “on-orbit” calibration plan, the observing plan, and the projected performance of the instrument.