Europlanet Science Congress 2021
Virtual meeting
13 – 24 September 2021
Europlanet Science Congress 2021
Virtual meeting
13 September – 24 September 2021

SB3

Laboratory measurements supporting modelling of early solar system processes and small bodies missions

This session aims to highlight new challenges and the missing building blocks needed to understand the composition and physical properties of the material of primitive bodies, using laboratory work on meteorites or other available extraterrestrial materials as well as terrestrial reference materials (rocks, minerals, ice, organics). Results of these laboratory studies with relevant references to modelling early processes in the solar system, including the formation/evolution of small bodies, and in support of ongoing and planned missions to study these objects are welcome.
The session focuses on the origin of inorganic and organic matter in different astrophysical environments and welcomes contributions on laboratory investigations and models of parent bodies of various meteorite groups, IDPs, asteroids, comets and dwarf planets.
This includes experimental work on the composition and physical properties of dust regoliths, the observation and characterization of laboratory analogues and resulting implications for models of small body formation and evolution. In addition, there is a special focus on organic matter (detection and evolution of organic components in the interstellar medium, observation and distribution of organic matter in the protosolar disk, characterization and evolution of organic matter in the primitive bodies and on planetary surfaces).

Public information:

Dear SB3 contributers,

Thank you again for your contributions during the live session on Thursday, September 16.

In the middle of the conference, I would like to ask you to please answer any questions you may have via Slack in order to promote the exchange of results.

So check back from time to time.

Gabriele

Convener: Gabriele Arnold | Co-conveners: Jörn Helbert, Eric Quirico
Public information:

Dear SB3 contributers,

Thank you again for your contributions during the live session on Thursday, September 16.

In the middle of the conference, I would like to ask you to please answer any questions you may have via Slack in order to promote the exchange of results.

So check back from time to time.

Gabriele

Session assets

Discussion on Slack

Oral and Poster presentations and abstracts

Chairpersons: Gabriele Arnold, Eric Quirico, Jörn Helbert
EPSC2021-11
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ECP
Victoria Munoz-Iglesias, Maite Fernández-Sampedro, Carolina Gil-Lozano, Laura J. Bonales, Oscar Ercilla Herrero, María Pilar Valles González, Eva Mateo-Martí, and Olga Prieto-Ballesteros

Ceres, dwarf planet of the main asteroid belt, is considered a relic ocean world since the Dawn mission discovered evidences of aqueous alteration and cryovolcanic activity [1]. Unexpectedly, a variety of ammonium-rich minerals were identified on its surface, including phyllosilicates, carbonates, and chlorides [2]. Although from the Dawn’s VIR spectroscopic data it was not possible to specify the exact type of phyllosilicates observed, montmorillonite is considered a good candidate owing to its ability to incorporate NH4+ in its interlayers [3]. Ammonium-rich phases are usually found at greater distances from the Sun. Hence, the study on their stability at environmental conditions relevant to Ceres’ interior and of its regolith can help elucidate certain ambiguities concerning the provenance of its precursor materials.

In this study, it was investigated the changes in the spectroscopic signatures of the clay mineral montmorillonite after (a) being immersed in ammonium chloride aqueous solution and, subsequently, (b) washed with deionized water. After each treatment, samples were submitted to different environmental conditions relevant to the surface of Ceres. For one experiment, they were frozen overnight at 193 K, and then subjected to 10-5 bar for up to 4 days in a Telstar Cryodos lyophilizer. For the other, they were placed inside the Planetary Atmospheres and Surfaces Chamber (PASC) [4] for 1 day at 100 K and 5.10-8 bar. The combination of different techniques, i.e., Raman and IR spectroscopies, XRD, and SEM/EDX, assisted the assignment of the bands to each particular molecule. In this regard, the signatures of the mineral external surface were distinguished from the interlayered NH4+ cations. The degree of compaction of the samples resulted crucial on their stability and spectroscopic response, being stiff smectites more resistant to low temperatures and vacuum conditions. In ground clay minerals, a decrease in the basal space with a redshift of the interlayered NH4+ IR band was measured after just 1 day of being exposed to vacuum conditions.

Acknowledgments

This work was supported by the Spanish MINECO projects ESP2017-89053-C2-1-P and PID2019-107442RB-C32, and the AEI project MDM‐2017‐0737 Unidad de Excelencia “María de Maeztu”.

References

[1] De Sanctis et al.,  Space Sci. Rev. 216, 60, 2020

[2] Raponi et al., Icarus 320, 83,  2019

[3] Borden and Giese, Clays Clay Miner. 49, 444, 2001

[4] Mateo-Marti et al., Life 9, 72, 2019

How to cite: Munoz-Iglesias, V., Fernández-Sampedro, M., Gil-Lozano, C., J. Bonales, L., Ercilla Herrero, O., Valles González, M. P., Mateo-Martí, E., and Prieto-Ballesteros, O.: Characterization of NH4-montmorillonite coexisting with NH4Cl salt at different aggregation states. Application to Ceres., Europlanet Science Congress 2021, online, 13–24 Sep 2021, EPSC2021-11, https://doi.org/10.5194/epsc2021-11, 2021.

EPSC2021-397
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ECP
Fabrizio Dirri, Anna Galiano, Andrea Longobardo, Ernesto Palomba, Bernard Schmitt, Pierre Beck, Olivier Poch, and Olivier Brissaud

Introduction

The VIR spectrometer on board the NASA’s Dawn spacecraft allowed providing important clues  the mineralogical composition of the Ceres regolith (De Sanctis et al., 2015) and of the bright areas widespread across its surface (Palomba et al., 2019; Carrozzo et al., 2018). Some bright spots are thought to be the result of phenomena like cryovolcanism (Ruesch et al., 2016; Russell et al., 2016) and post-impact hydrothermal activities (Bowling et al., 2016). The study of Ceres bright areas is important to understand in more detail the mineralogical composition of the subsurface materials that could host water ice (Prettyman et al., 2017; Schmidt et al., 2017) or have been under aqueous alteration (De Sanctis et al., 2016). 

In this study different bright areas of Haulani crater (e.g. Southern floor, i.e. ROI3 and North-east crater wall, i.e. ROI4) on Ceres have been studied by creating different analogue mixtures and comparing them with Dawn VIR data. The end-members have been identified based on previous studies (Tosi et al. 2018, 2019) and the analogue mixtures have been produced with grain size 50-100 µm for two bright crater regions. The spectra of two initial analogue mixtures have been acquired in the VIS-NIR spectral range (0.35-4.5 µm) at low temperature, i.e. from 200 K to 300 K similar to Haulani by using the Cold Spectroscopy Facility (CSS; https://cold-spectro.sshade.eu) (IPAG, France).

 

Scientific goals and method

The main scientific objectives of this study are: 1) the study of two different bright areas of Haulani crater (hereafter called ROI3 and ROI4, Figure 1) on Ceres in order to study the mineralogy  of the sub-surface materials starting from results inferred by Dawn VIR; 2) the identification of the end-members of mineral mixtures of bright areas and production of endmembers and analogue mixtures  with grain size 50-100 µm; 3) the acquisition of reflectance spectra of end-members and analogue mixtures in the VIS-NIR spectral range (0.35-4.5 µm); 4) the analysis of appropriate spectral parameters of reflectance spectra and comparison with those obtained by VIR data.

In particular, spectral parameters of mixtures will be estimated, focusing on Band Center (BC), Band Depth (BD), Full Width Half at Maximum (FWHM) of bands, reflectance level and spectral slopes (estimated between 1.2 and 1.9 µm). The spectral parameters of analogue mixtures have been compared with the VIR data corresponding to the selected area in order to constrain their mineralogical composition.

 

Data analysis and conclusion

Two analogue mixtures (50-100 µm), here called A3-1 and A3-2 have been produced by using the end-members Antigorite (Mg-phyllosilicate); NH4-montmorillonite (ammoniated phyllosilicate); anhydrous Sodium Carbonate (Na-carbonate); Graphite (dark component), Illite (Phyllosilicates) to simulate the two bright crater regions (Figure 1, i.e. southern floor and red spot or ROI3, i.e. north-east inner crater wall or ROI4). Reflectance spectra of the two mixtures have been acquired in the VIS-NIR spectral range (0.35-4.5 µm) at cold temperature, i.e., from 200 K to 300 K (phase angle of 30°) with the SHINE spectro-gonio-radiometer equipped with the CARBONIR simulation chamber (sample in inner cell filled with few mbar of pure N2 gas) at the Cold Spectroscopy Facility (CSS) in IPAG, France (Figure 1, Right). Finally, the analysis of spectral parameters of the reflectance spectra (mainly relative to the absorption bands at 2.7, 3.1, 3.4 µm) and the comparison with VIR data have been performed. The acquired spectra have been finally converted in radiance factor. 

A first analysis shows that the Mixture A3-1 and A3-2 are not well representative due to the high amount of dark components (up to 86 % for A3-1) and missing Na-carbonate bands (for A3-2). Thus, the A3-2 has been modified (by producing the intermediate mixture) and by reaching 9 % for Na-carbonate, 32 % of dark component (i.e. carbon black) and 25 % of NH4-Montmorillonite in the final mixture named as A3-8. Finally, graphite and NH4-montmorillonite have been added to the A3-8 mixture, obtaining the last mixture A3-9. Thanks to carbon black the reflectance level compared with Haulani spectra is more similar. The analysed mixture were heated in the furnace in air at 120°C for 2 hours before each measurement and then placed in the sample holder under vacuum to remove the adsorbed H2O.

The mixtures with a reflectance spectrum similar to the spectra of ROI3 and ROI4 have been analysed in detail. By the spectral analysis, the Mixture A3-8 shows the most representative reflectance spectrum for the Haulani’s areas of interest (even if the difference in the reflectance level is probably due to opaque end-member composition) and exhibits BD values for the 2.7, 3.1 and 3.4  µm bands that are the closest one to the ROI3 and ROI4. The width of the 3.1 µm band (3.1FWHM) of A3-8 has a value similar  to the ROI4 (about 0.15). In particular, the 2.7 BD is about 13% lower than ROI3 and ROI4, the 3.1BD is 5-9% higher while the 3.4BD has the same value of ROI4 and 11% lower than ROI3. A more in-depth analysis of the data is in progress.

Besides, in order to better reproduce Haulani areas some improvements may be performed, e.g., by adding a low amount of hydrous natrite , e.g. 2-8%, to assess the role of this component found in Haulani bright areas and how it contributes to the 2.7 µm spectral band.    

 

References

Carrozzo, F.G., et al., 2018. Nature, Sci. Adv. 4 (3); De Sanctis. M. C. et al., 2015. Nature 528, pp. 241-244; De Sanctis, M.C., et al., 2016. Nature 536. Issue 7614, 54–57; Palomba, E., et al., 2019. Icarus 320, 202–212; Prettyman T. H., et al., 2017. Science 355:55–59; Ruesch, O., et al., 2016. Science 353 (6303); Russell, C.T., et al., 2016. Science 353 (6303), 1008–1010; Schmidt B. E. et al., 2017. Nature Geoscience 10:338–343; Tosi, F. et al., 2018. M&P Sci. 53, Nr.9, pp. 1902-1924; Tosi, F. et al., 2019. Icarus 318, pp.170-187.

How to cite: Dirri, F., Galiano, A., Longobardo, A., Palomba, E., Schmitt, B., Beck, P., Poch, O., and Brissaud, O.: VIS-NIR reflectance analysis of analogue mixtures representative of Haulani crater on Ceres to assess the mineralogical composition of bright areas , Europlanet Science Congress 2021, online, 13–24 Sep 2021, EPSC2021-397, https://doi.org/10.5194/epsc2021-397, 2021.

EPSC2021-723
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ECP
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solicited
Giovanni Poggiali, Maria Cristina De Sanctis, John Robert Brucato, Marco Ferrari, Simone De Angelis, Maria Elisabetta Palumbo, Giuseppe Baratta, Vito Mennella, Daniele Fulvio, Ciprian Popa, Giovanni Strazzulla, and Carlotta Sciré

Summary

Ceres is the largest object in the Solar System main belt. Clearly, Ceres experienced extensive water-related processes and geochemical differentiation and nowadays it is a body with a complex geological and chemical history [1]. Its surface is characterized by dark materials, phyllosilicates, ammonium-bearing minerals, carbonates, water ice, and salts. In addition to a global presence of carbon bearing chemistry, local concentration of aliphatic organics has been detected by Dawn [2].

In this context, we have started a series of laboratory spectroscopy measurements targeted to study the physicochemical interactions between organic material and minerals possibly present on Ceres. The goal is to understand the transformations induced on these samples by ultraviolet radiation, neutral atoms, and fast ions, under experimental conditions that simulate the environment of Ceres. The spectroscopic data obtained in laboratory experiments allow, through the comparison with the observations of the VIR spectrometer aboard the Dawn mission, to clarify the nature and origin of organic material identified on Ceres. 

Introduction

Organic material in the minor bodies of the Solar System is an important component to understand planetary evolution and, eventually, the origin of life. Nevertheless, our knowledge on the subject is still limited. Recently the Dawn mission, thanks to the data collected by the Italian instrument VIR [3], showed clear evidence of a high amount of aliphatic organic material on the surface of Ceres [4, 5, 6] (Fig 1). This evidence has raised new questions about the origin and preservation of this material, especially when considering its high estimated abundance and the mineralogical context.

 

Fig 1 Ceres spectra of the organic-rich area in Ernutet crater (label “Organics”); of a background organic-poor area from a region southeast of Ernutet (label “Background”); and of Occator bright material (label “Carbonate”) [4].

 

In order to understand the organic chemical species and in particular their abundance on Ceres, laboratory studies were performed [7]. The importance of having a direct comparison between laboratory and remote sensing data can provide a further investigation clues to shed light on the origin and evolution of Ceres. Through this project, we intend to study, through dedicated experiments, the interaction between minerals, water, and organic concerning the environmental conditions of Ceres. Making a synergistic use of complementary and indispensable skills present within INAF (Italian National Institute of Astrophysics) laboratories we investigated a complex issue such as that concerning the origin and preservation of organic molecules on planetary surfaces. Within INAF, complementary and unique realities coexist which, thanks to joint and coordinated work, can give a new interpretation of the physical-chemical processes active on Ceres.

Project development and results

In this study, we prepare mixtures of materials resembling the Ceres surface composition [8, 9] adding organic molecules in order to:

(i) understand how organic molecules behave and eventually degrade on Ceres, in particular, how aliphatic molecules degrade by energetic processing with fast ions (keV-MeV) and UV photons [10, 11]. Moreover, the physico-chemical properties of the materials exposed to a flux of neutral atoms are investigated [12, 13].

(ii) evaluate the interaction between ammoniated minerals and simple organic molecules that may lead to the synthesis of complex compounds. In the presence of ultraviolet (UV) radiation, these minerals present on the surface of Ceres can show photocatalytic effects accelerating the photo-reactions, which generally destroy the original organic molecule and in the synthesis of new complex organic molecules [14].

(iii) evaluate the role of minerals in the protection or degradation of organic compounds. Some studies indicated a fundamental role of clays in the catalysis and preservation of organic materials [15]. Ceres is rich in clays and other hydrated minerals, making the interactions with the observed organics of particular interest.

The project is carried out by several INAF institutes and laboratories. In detail: INAF-IAPS Istituto di Astrofisica e Planetologia Spaziali prepared the analog mineral mixtures taking into account the compositional information gained by VIR observations.  INAF - Osservatorio Astrofisico di Arcetri subsequently doped the mixture with several organic investigating UV photostability in Ceres analog conditions and the influence of temperature. INAF -Osservatorio Astronomico di Capodimonte studied irradiation with atoms and temperature effect while INAF - Osservatorio Astrofisico di Catania performed irradiation with fast ions. Finally, results of laboratory measurements were compared with data obtained by VIR instrument onboard Dawn mission.

Acknowledgements
This work is support by INAF Main Stream programme, grant  1.05.01.86.08 Evoluzione ed alterazione del materiale organico su Cerere (ref. Maria Cristina De Sanctis).

References

[1] De Sanctis et al., 2016, Nature 536, 54–57

[2] Marchi et al., Nature Astr., 2019

[3] De Sanctis et al., 2011, Space Science Reviews 163, 329-369.

[4] De Sanctis et al., science 2017 355, 719

[5] Pieters et al., 2018, Meteoritics and Planetary Science 53 (9), 1983-1998

[6] De Sanctis et al., 2019, 482 (2), 2407–2421

[7] Vinogradoff et al., 2021

[8] Ferrari et al., 2019, Icarus 321, 522-530

[9]De Angelis et al., 2021 JGR Planets doi: 10.1029/2020JE006696

[10] Baratta et al. 2002, A&A, 384, 343-349

[11] Brucato et al. 2006, A&A, 455, 395-399

[12] Mennella et al. 2003, ApJ, 587, 727-738

[13] Palumbo et al 2004, Ad. Sp. Res., 33, 49-56

[14] Fornaro et al. 2013, Icarus, 226(1), 1068–1085

[15] Fornaro et al 2018, Astrobiology, 18, 989-1007

How to cite: Poggiali, G., De Sanctis, M. C., Brucato, J. R., Ferrari, M., De Angelis, S., Palumbo, M. E., Baratta, G., Mennella, V., Fulvio, D., Popa, C., Strazzulla, G., and Sciré, C.: Evolution and alteration of organic material on Ceres, a pathway towards the understanding of complex geological and chemical history of a wet small body, Europlanet Science Congress 2021, online, 13–24 Sep 2021, EPSC2021-723, https://doi.org/10.5194/epsc2021-723, 2021.