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Abstract In the tenuous atmospheric bodies of our solar system, space weathering on the celestial surface is an important process for its chemical and physical evolution and ambient environment on timescales of celestial evolution. Space plasma is a dominant energy and material source for space weathering. Plasma irradiation experiment in the laboratory is an effective method for modeling space weathering driven by space plasma. However, comprehensive modeling of plasma space weathering has not yet been conducted because the capabilities of the earlier facilities were not optimized for realistic space weathering; for example, the incident electron and ion were not irradiated in the same condition. Here, we developed a plasma irradiation system, Plasma Irradiation Emulator for Celestial Environments (PIECE) of the solar system bodies, which reproduces plasma space weathering in tenuous atmospheric bodies by the electron and ion irradiations in the same condition. We successfully developed a system with high electron and ion number fluxes of $$\sim 10^{13} - 10^{16} {\text{ particles cm}}^{{ - {2}}} {\text{s}}^{{ - {1}}}$$ ∼ 10 13 - 10 16 particles cm - 2 s - 1 at any acceleration energy in the range of 1–30 keV, which leads to a fluence of e.g., $$\sim 10^{18} - 10^{21} {\text{ particles cm}}^{{ - {2}}} {\text{s}}^{{ - {1}}}$$ ∼ 10 18 - 10 21 particles cm - 2 s - 1 , with a 1-day irradiation time. This fluence corresponds to a plasma irradiation time of ~ 103–106 years on Europa. Graphical Abstract

Abstract We conducted ground-based performance evaluation tests of the Near-Infrared Spectrometer (NIRS3) onboard Hayabusa2 spacecraft in November 2013 and from April to May 2014 and established a method for evaluating its measured reflectance spectra. Reflectance spectra of nine powdered carbonaceous chondrite samples were measured by both NIRS3 and a Fourier transform infrared (FT-IR) spectrometer. We have established two methods for correcting the NIRS3 data by comparing them with the corresponding FT-IR data because raw data obtained by NIRS3 underwent spectral distortion caused by systematic offsets in sensitivity of individual pixels. The corrected NIRS3 spectra of carbonaceous chondrite samples are comparable with their FT-IR spectra. The depth of each band component D λ is defined for each wavelength λ (μm) to characterize the absorption bands in NIRS3 spectra. It is suggested that the relationship between the D 2.72/D 2.79 ratio and the D 2.76/D 2.90 ratio would be useful for estimating the degree of heating of the asteroid surface, if contributions of terrestrial adsorbed water on D 2.79 and D 2.90 are properly corrected. The degrees of heating and space weathering are also comprehensively evaluated by the relationship between D 2.90 and the D 2.76/D 2.90 ratio. Reflectance spectra of asteroid Ryugu, the target asteroid of Hayabusa2, to be recorded by the NIRS3 instrument are expected to reveal the characteristics of the surface materials by using the evaluation technique proposed in this paper. Such information will be used for choosing the touchdown points for sampling and also for investigating the distribution of the materials similar to the returned samples on Ryugu. Graphical abstract .