International Journal of Astrobiology cambridge.org/ija Research Article Cite this article: Nascimento-Dias BL, Zucolotto ME, Belgo HC, da Silva TVF, Anjos VdeC (2020). Detection of organic or inorganic material in Martian meteorite Zagami by vibrational spectroscopy? International Journal of Astrobiology 19, 438–445. https://doi.org/ 10.1017/S147355042000021X Received: 14 June 2020 Revised: 27 July 2020 Accepted: 7 August 2020 First published online: 14 September 2020 Key words: FTIR; Mars; Raman; Zagami meteorite Author for correspondence: Bruno Leonardo do Nascimento-Dias, E-mail: bruno.astrobio@gmail.com © The Author(s), 2020. Published by Cambridge University Press Detection of organic or inorganic material in Martian meteorite Zagami by vibrational spectroscopy? Bruno Leonardo do Nascimento-Dias 1 , Maria Elizabeth Zucolotto 2 , Hugo Camarano Belgo 1,3 , Talita Valverde Ferreira da Silva 3 and Virgĩlio de Carvalho dos Anjos 1 1 Physics, Universidade Federal de Juiz de Fora, Juiz de Fora, Brazil; 2 Geology, Universidade Federal do Rio de Janeiro Museu Nacional, Rio de Janeiro, Brazil and 3 Chemistry, Universidade Federal de Juiz de Fora, Juiz de Fora, Brazil Abstract Zagami is a basaltic shergottite well characterized among Martian meteorites. For this reason, it is used as a reference sample to verify the feasibility of the vibrational spectroscopy techni- ques. In general, these techniques seeking extract spectral signatures from individual mineral present in the meteorite samples. Among some FTIR results were detected organic com- pounds in the Zagami meteorite and recorded in some articles. Based on these results, an ana- lysis of a Zagami meteorite sample was performed using FTIR and Raman spectrometry. Examining the fragment of Zagami meteorite using the FTIR technique, it was possible to identify the same band of 2920 and 2850 cm -1 described by other references, which were interpreted as organic components and were recorded such as aliphatic hydrocarbon. Another unusual result in Martian meteorite was the detection of the 1300 cm -1 band using Raman. The main reason for this peculiarity is that band is characterized in meteorites as a D band. Generally, this band is attributed to structural defects and the disordering of car- bon. However, care should be taken when interpreting Raman spectra around 1300cm -1 and FTIR spectra 2950–2840 cm -1 of the sample from oxidizing environments such as Mars. Misconceptions can occur during the interpretations of the bands, and this can lead to incor- rect identification. Thus, an analysis of the mentioned peaks, such as chemical and mineral- ogical assignments, will be provided and suggested in order to compare the results that mentioned the presence of organic compounds in the Zagami meteorite. Introduction Martian meteorites are considered important pieces of geological material from Mars. Although most of the geological records have been destroyed, as happened on Earth, the geo- logical evolution of the Martian surface, its physical information and chemical characteristics can still be studied through the Martian meteorites (Nimmo and Tanaka, 2005). In general, Martian meteorites are divided into Shergottites, Nakhlites and Chassignites (SNC). The SNC meteorite group includes igneous rocks (basalts and cumulates) which generally contain evidence for shock impact metamorphism, such as glass veins and cracks. Zagami meteorite is a very famous shergottite, and has been well studied (McCoy et al., 1999; Wang et al., 1999; Nyquist et al., 2001). Some of these studies detected organic com- pounds in the Zagami meteorite and recorded in some articles (Anderson et al., 2005; Palomba et al., 2006). Thus, one of the main intentions of this work is to analyse the spectral signature obtained by vibrational spectrometry and compare the result with spectral composi- tions of the same sample that reported the presence of organic compounds. According to Anderson et al.(2005), infrared spectroscopy would be an obvious choice as part of an instrument for analysing Martian samples. In particular, the molecular bond infor- mation provided by vibrational spectrometry, such as Raman and FTIR, adds powerful inter- pretive information to methods that yield only elemental composition. Finally, it can be said that this research conforms to the focal point for searching for traces of life in the Solar System, which is Mars. The main reason for this attribution to Mars is because of its geological similarity and proximity to Earth. Thus, information obtained from Martian meteorites may provide important implications for the study of life or habitability conditions that might have existed in the Solar System. However, it is worth noting that although there are results pointing to the existence of organic compounds in Martian meteorites, such as in Zagami meteorite, it is always necessary to carefully ascer- tain such attributions. https://doi.org/10.1017/S147355042000021X Downloaded from https://www.cambridge.org/core. IP address: 35.175.192.15, on 16 Oct 2021 at 14:10:07, subject to the Cambridge Core terms of use, available at https://www.cambridge.org/core/terms.