Goniometers
The goniometers part of PLANETIPAG is composed of two spectro-gonio radiometers SHINE and SHADOWS developed at IPAG. They allow measurement of bidirectional reflectance spectra and photometric distribution functions of various types of planetary materials (granular to compact), from visible to near IR (from 0.4 to 4.8 µm), with high radiometric accuracy ( better than +/- 0.5% relative) under most geometries (illumination and observation up to almost 80°, azimuths 0° to 180°, phase angle 5° to 160°)
The instruments are located in two dark cold rooms which can be cooled to -20° C. They are fully automated, calibration and data acquisition are performed with software developed in the laboratory. Different types of measurements can be programmed with different environmental cryogenic cells.
The SHINE instrument is fully described in Brissaud et al. 2004, Appl. Optics, 43, 1926 :
– measurements: reflectance, samples: powders, ice, mixtures, various surfaces (from 10 to 300 mm in diameter, thickness from 1 to 250 mm depending on the absorbance of the grains)
The SHADOWS instrument is fully described in Potin et al. 2018, Appl. Optics, 57, 8279 :
– reflectance measurements: samples: powders, ice, mixtures, various surfaces ( 2 mm (in micro-beam mode) or 5.7 mm (in normal mode) minimum diameter, thickness from 0.25 to 2.5 mm depending on the absorbance of the albedo grains from 0.0003 to 1).
– transmittance measurements: samples: deposits / films on optical windows
This installation is one of the experimental platforms of the ’Trans-National Access’ activity of the Europlanet 2024-RI program
– De Angelis, S. et al. (2021). Temperature-dependent, VIS-NIR reflectance spectroscopy of sodium sulfates, Icarus, 357, 114165. https://doi.org/10.1016/j.icarus.2020.114165
– Potin, S. et al. (2020). Style and intensity of hydration among C-complex asteroids: a comparison to desiccated carbonaceous chondrites. Icarus, 348, 113826. https://doi.org/10.1016/j.icarus.2020.113826
– Poch, O. et al. (2020). Ammonium salts are a reservoir of nitrogen on a cometary nucleus and possibly on some asteroids, Science 367, 10.1126/science.aaw7462.
– Sultana, R., O. Poch, P. Beck, B. Schmitt and E. Quirico (2021). Visible and Near-Infrared reflectance of hyperfine and hyperporous particulate surfaces. Icarus. https://doi.org/10.1016/j.icarus.2020.114141