Transmittance, Reflectance and Emission Spectroscopy of Meteorites from the IV to the IR Spectral Range

Abstract

In the last decade the Planetary Emissivity Laboratory (PEL) of DLR in Berlin has provided spec-tral measurements of planetary analogues from the visible to the far-infrared range for comparison with remote sens-ing spacecraft/telescopic measurements of planetary surfaces [1-5]. Bi-directional reflection, transmission and emis-sion spectroscopy are the techniques we used to acquire spectral data of target materials. In fall 2015 we started upgrading our laboratory set-up, adding a new spectrometer, three external sources, and new detectors and beamsplitters to further extend the spectral range of measurements that can be performed in the laboratory. Reflecting the wider scope of measurement capabilities the facility was renamed to Planetary Spectros-copy Laboratory (PSL). Two FTIR instruments are operating at PSL, in an air-conditioned room. The spectrometers are two Bruker Ver-tex 80V that can be evacuated to ~.1 mbar. One spectrometer is equipped with aluminum mirrors optimized for the UV, visible and near-IR, the second features gold-coated mirrors for the near to far IR spectral range. Apart from the mirrors the two instruments are identical, and can therefore share the collection of detectors and beamsplitters we have in our equipment to cover a very wide spectral range. The instruments and the accessory units used are fully automatized and the data calibration and reduction are made with software developed at DLR[4]. By using several pairings of detector+beamsplitter we can perform spectral measurements in the whole spectral range from 0.2 to 200 μm.