HERMES

The Heliophysics Environmental and Radiation Measurement Experiment Suite (HERMES) is an instrument payload that is mounted on the upcoming Lunar Gateway and will serve as a heliospheric science experiment and as a space weather station. The lunar gateway itself is a space station that is planned to be in a cislunar, near rectilinear halo orbit (NRHO) around the moon and will serve as a short-term habitation module for humans and holding area for rovers, but will also serve as a science laboratory. For this mission, the Space Sciences Laboratory (SSL) is building and leading the ion sensor, named after the Solar Probe ANalyzer for Ions (SPAN-I), which provides the science payload with measurements of ambient ions in both E/Q and M/Q. In total there are three main science goals that we will address: 1. Measure definitive atmospheric loss around Earth, 2. Measure solar wind acceleration with multipoint observations (e.g. ARTEMIS: Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s Interaction with the Sun), and 3. Resolve 3D solar wind structures. In addition, SPAN-I will have the capability of distinguishing between various heavy and molecular ions in Earth’s magnetotail and therefore provide new observations of ion outflow in Earth’s environment.

Instrument suite on a spacecraft orbiting Earth’s Moon. Text reads: HERMES The Heliophysics Environmental and Radiation Measurement Experiment Suite