A revolutionary technique for planetary science: Laser-induced Breakdown Spectroscopy (LIBS) is an active analytical technique that makes use of a pulsed laser to ablate material of interest at a distance. The atoms in the high temperature plasma emit at specific wavelengths from the UV to near-IR and the light can be analyzed by spectrometry to determine the composition of the target [1]. Since 2012, LIBS has been successfully used under low atmospheric pressure for exploring the geology of Mars at Gale Crater with the Mars Science Laboratory rover’s ChemCam instrument [2-4]. LIBS can be used to analyze single regolith mineral particles and larger rocks, giving major and minor elements compositions. Moreover, LIBS is sensitive to volatile elements (H, Na, etc.) that are of intrinsic interest to understand key planetary processes. The generated shock wave can also ablate dust covering rocks to allow further analysis by other instruments on the mission platform (rover, lander). In order to quantify the elemental composition of various targets, large laboratory samples analyses are required for calibration, with ChemCam’s calibration database containing more than 400 standards [5-6].
LIBS is becoming international: Due to its ease of deployment and rapidity of analysis, LIBS has shown a great potential as a chemistry survey instrument for the next generation of in situ space missions to planets, satellites and small bodies. In the next couple of years, three more LIBS space instruments will be sent for planetary exploration by teams representing several different nationalities In 2018, the Indian space mission to the Moon Chandrayaan 2 will comprise a rover equipped with a small portable LIBS instrument for regolith reconnaissance around the landing site [7]. In 2020, the next NASA Mars rover will carry the SuperCam instrument, a follow-up of the ChemCam instrument, which will combine the LIBS technique with Raman and IR analyses for mineralogical assessment [8] in a collaboration involving several different European countries. Finally, the China Academy of Space Technology is developing a combined orbiter and rover mission for exploring Mars by 2020 [9]. The Chinese rover will also be equipped with a LIBS survey instrument. In the framework of these near future missions, it is important to develop strategies to assess the potential for combined analysis of these different in situ instruments.
Goals of the ISSI International Team: In the framework of the ISSI/ISSI-BJ Joint Call for Proposals 2018 for International Teams in Space and Earth Sciences, we intend to submit a proposal to gather a team of LIBS specialists from all the major countries currently involved in the use of LIBS for space exploration (USA, Europe, Japan, India, China) to meet and exchange information during a couple of workshops in 2018-2019.
The goals of the team will be fourfold:
- Assess the potential for combined analysis of the data by sharing and discussing the
technical details of each instrument design. - Discuss the calibration procedures of each instrument and share the relevant tools
(databases, software, calibration targets, etc.) to determine the best methods to develop potential cross-calibration between the four instruments. - Develop and share the tools necessary for comparing the analyses made by the four
instruments for the 2020 timeline, as an international effort. - Define a set of recommendations to facilitate the use of the technique for future planetary missions.
The full version of the proposal submitted to ISSI can be found here: ISSI_WG_LIBS_prop_final
References:
[1] Cremers D.A. and Radziemski L.J. (2006) Handbook of Laser-Induced Breakdown
Spectroscopy.
[2] Wiens R.C. et al. (2012) SSR DOI : 10.1007/ s11214-012-9902-4.
[3] Maurice S. et al. (2012) SSR, DOI: 10.1007/ s11214-012-9912-2.
[4] Maurice S. et al. (2016) JAAS, DOI: 10.1039/ c5ja00417a.
[5] Wiens R. C. et al. (2013) Spectrochimica Acta Part B: Atomic Spectroscopy, 82, 1-27.
[6] Clegg S. M. et al. (2017) Spectrochimica Acta Part B: Atomic Spectroscopy, 129, 64-85.
[7] Laxmiprasad et al. (2013) ASR, 52(2), 332
[8] Wiens R. C. et al. (2017) Spectroscopy, 32(5), 50-55.
[9] https://gbtimes.com/china-reveals-more-details-its-2020-mars-mission