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Acceso Abierto
Magnetic field morphology and evolution in the Central Molecular Zone and its effect on gas dynamics
(EDP Sciences, 2024-11-22) Tress, Robin; Sormani, Mattia Carlo; Girichidis, P.; Glover, Simon; Klessen, Ralf Stephan; Smith, Rowan; Sobacchi, E.; Armillotta, Lucia; Barnes, A. T.; Battersby, C.; Bogue, Kamran R. J.; Brucy, Noé; Colzi, Laura; Federrath, C.; García, Pablo; Ginsburg, A.; Göller, Junia Aletta Beatrix; Hatchfield, H. P.; Henkel, C.; Hennebelle, P.; Henshaw, J. D.; Hirschmann, M.; Hu, Y.; Kauffmann, J.; Kruijssen, J. M. D.; Lazarian, A.; Lipman, Dani R.; Longmore, S. N.; Morris, Mark; Nogueras Lara, Francisco; Petkova, Maya A.; Pillai, Thushara; Rivilla, Victor M.; Sanchez-Monge, Alvaro; Soler, Juan Diego; Whitworth, David; Zhang, Qizhou; European Research Council (ERC); Royal Society; National Science Foundation (NSF); Consejo Superior de Investigaciones Científicas (CSIC); European Commission (EC); Deutsche Forschungsgemeinschaft (DFG); Ministerio de Ciencia e Innovación (MICINN); Agencia Estatal de Investigación (AEI); Chinese Academy of Science (CAS); Consejo Nacional de Ciencia y Tecnología (CONACyT); Unidad de Excelencia Científica María de Maeztu INSTITUTO DE CIENCIAS DEL ESPACIO, CEX2020-001058-M
The interstellar medium in the Milky Way’s Central Molecular Zone (CMZ) is known to be strongly magnetised, but its large-scale morphology and impact on the gas dynamics are not well understood. We explore the impact and properties of magnetic fields in the CMZ using three-dimensional non-self gravitating magnetohydrodynamical simulations of gas flow in an external Milky Way barred potential. We find that: (1) The magnetic field is conveniently decomposed into a regular time-averaged component and an irregular turbulent component. The regular component aligns well with the velocity vectors of the gas everywhere, including within the bar lanes. (2) The field geometry transitions from parallel to the Galactic plane near ɀ = 0 to poloidal away from the plane. (3) The magneto-rotational instability (MRI) causes an in-plane inflow of matter from the CMZ gas ring towards the central few parsecs of 0.01−0.1 M⊙ yr−1 that is absent in the unmagnetised simulations. However, the magnetic fields have no significant effect on the larger-scale bar-driven inflow that brings the gas from the Galactic disc into the CMZ. (4) A combination of bar inflow and MRI-driven turbulence can sustain a turbulent vertical velocity dispersion of σɀ = 5 km s−1 on scales of 20 pc in the CMZ ring. The MRI alone sustains a velocity dispersion of σɀ ≃ 3 km s−1. Both these numbers are lower than the observed velocity dispersion of gas in the CMZ, suggesting that other processes such as stellar feedback are necessary to explain the observations. (5) Dynamo action driven by differential rotation and the MRI amplifies the magnetic fields in the CMZ ring until they saturate at a value that scales with the average local density as B ≃ 102 (n/103 cm−3)0.33 µG. Finally, we discuss the implications of our results within the observational context in the CMZ.
Acceso Abierto
The Galaxy Activity, Torus, and Outflow Survey (GATOS) V. Unveiling PAH survival and resilience in the circumnuclear regions of AGNs with JWST
(EDP Sciences, 2024-09-09) García-Bernete, Ismael; Rigopoulou, D.; Donnan, Fergus; Alonso-Herrero, Almudena; Pereira-Santaella, Miguel; Shimizu, T. Taro; Davies, Richard; Roche, P. F.; García-Burillo, Santiago; Labiano, Alvaro; Hermosa Muñoz, Laura; Zhang, Lulu; Audibert, A.; Bellocchi, Enrica; Bunker, A.; Combes, Francoise; Delaney, D.; Esparza-Arredondo, D.; Gandhi, P.; González-Martín, O.; Hönig, Sebastian; Imanishi, Masatoshi; Hicks, Erin K. S.; Fuller, L.; Leist, Mason Tanner; Levenson, N. A.; López-Rodríguez, E.; Packham, Christopher; Ramos Almeida, Cristina; Ricci, C.; Stalevski, Marko; Villar Martín, M.; Ward, M. J.; Science and Technology Facilities Council (STFC); Comunidad de Madrid; European Commission (EC); European Space Agency (ESA); Fondo Nacional de Desarrollo Científico y Tecnológico (FONDECYT); Ministerio de Ciencia e Innovación (MICINN); National Aeronautics and Space Administration (NASA); Space Telescope Science Institute (STScI); Universidad Nacional Autónoma de México (UNAM)
This study analyses JWST MIRI/MRS observations of the infrared (IR) polycyclic aromatic hydrocarbon (PAH) bands in the nuclear (∼0.4″ at 11 μm; ∼75 pc) and circumnuclear regions (inner ∼kpc) of local active galactic nuclei (AGNs) from the Galactic Activity, Torus, and Outflow Survey (GATOS). We examine the PAH properties in the circumnuclear regions of AGNs and the projected direction of AGN-outflows and compare them to those in star-forming regions and the innermost regions of AGNs. This study employs 4.9–28.1 μm sub-arcsecond angular resolution data to investigate the properties of PAHs in three nearby sources (DL ∼ 30 − 40 Mpc). Our findings are aligned with previous JWST studies, demonstrating that the central regions of AGNs display a larger fraction of neutral PAH molecules (i.e. elevated 11.3/6.2 and 11.3/7.7 μm PAH ratios) in comparison to star-forming galaxies. We find that AGNs might affect not only the PAH population in the innermost region, but also in the extended regions up to ∼kpc scales. By comparing our observations to PAH diagnostic diagrams, we find that, in general, regions located in the projected direction of the AGN-outflow occupy similar positions on the PAH diagnostic diagrams as those of the innermost regions of AGNs. Star-forming regions that are not affected by the AGNs in these galaxies share the same part of the diagram as star-forming galaxies. We also examined the potential of the PAH-H2 diagram to disentangle AGN-versus-star-forming activity. Our results suggest that in Seyfert-like AGNs, the illumination and feedback from the AGN might affect the PAH population at nuclear and kpc scales, particularly with respect to the ionisation state of the PAH grains. However, PAH molecular sizes are rather similar. The carriers of the ionised PAH bands (6.2 and 7.7 μm) are less resilient than those of neutral PAH bands (11.3 μm), which might be particularly important for strongly AGN-host coupled systems. Therefore, caution must be applied when using PAH bands as star-formation rate indicators in these systems even at kpc scales, with the effects of the AGN being more important for ionised ones.
Acceso Abierto
Polycyclic aromatic hydrocarbon emission in galaxies as seen with JWST
(Royal Astronomical Society, 2024-08-01) Rigopoulou, D.; Donnan, F. R.; García-Bernete, I.; Pereira Santaella, Miguel; Alonso-Herrero, Almudena; Davies, R.; Hunt, L. K.; Roche, P. F.; Shimizu, T.; Ministerio de Ciencia e Innovación (MICINN); Science and Technology Facilities Council (STFC)
We present a systematic study of mid-infrared spectra of galaxies including star-forming galaxies and active galactic nuclei observed with JWST MIRI-MRS and NIRSpec-IFU. We focus on the relative variations of the 3.3, 6.2, 7.7, 11.3, 12.7, and 17 m polycyclic aromatic hydrocarbon (PAH) features within spatially resolved regions of galaxies including NGC 3256, NGC 7469, VV 114, II Zw96, and NGC 5728. Using theoretical PAH models and extending our earlier work, we introduce a new PAH diagnostic involving the 17 m PAH feature. To determine the drivers of PAH band variations in galaxies, we compare observed PAH spectral bands to predictions from theoretical PAH models. We consider extinction, dehydrogenation, and PAH size and charge as possible drivers of PAH band variations. We find a surprising uniformity in PAH size distribution among the spatially resolved regions of the galaxies studied here, with no evidence for preferential destruction of the smallest grains, contrary to earlier findings. Neither extinction nor dehydrogenation play a crucial role in setting the observed PAH bands. Instead, we find that PAH charge plays a significant role in PAH inter-band variations. We find a tight relation between PAH charge and the intensity of the radiation field as traced by the [Ne iii][Ne ii] maps. In agreement with recent JWST results, we find a predominance of neutral PAH molecules in the nuclei of active galaxies and their outflows. Ionized PAHs are the dominant population in star-forming galaxies. We discuss the implications of our findings for the use of PAHs as ISM tracers in high redshift galaxies.
Acceso Abierto
Synthesis and Spectroscopic Characterization of Interstellar Candidate Ethynyl Thiocyanate: HCCSCN
(IOP Publishing, 2024-11-14) Alonso, Elena R.; Insausti, Aran; Kolesniková, Lucie; León, Iker; McGuire, Brett A.; Shingledecker, Christopher N.; Agúndez, Marcelino; Cernicharo, José; Rivilla, Victor M.; Cabezas, Carlos; Jimenez-Serra, Izaskun; Martín-Pintado, Jesús; Guillemin, Jean Claude; National Science Foundation (NSF); Junta de Castilla y León; European Commission (EC); El Consejo Superior de Investigaciones Científicas (CSIC); Centre National de la Recherche Scientifique (CNRS); Ministerio de Ciencia e Innovación (MICINN)
This work aims to spectroscopically characterize and provide for the first time direct experimental frequencies of the ground vibrational state and two excited states of the simplest alkynyl thiocyanate (HCCSCN) for astrophysical use. Both microwave (8-16 GHz) and millimeter-wave regions (50-120 GHz) of the spectrum have been measured and analyzed in terms of Watson’s semirigid rotor Hamiltonian. A total of 314 transitions were assigned to the ground state of HCCSCN, and a first set of spectroscopic constants have been accurately determined. Spectral features of the molecule were then searched for in Sgr B2(N), NGC 6334I, G+0.693−0.027, and TMC-1 molecular clouds. Upper limits to the column density are provided.
Acceso Abierto
AGN feedback in the Local Universe: Multiphase outflow of the Seyfert galaxy NGC 5506
(EDP Sciences, 2024-06-01) Esposito, Federico; Alonso-Herrero, Almudena; García-Burillo, Santiago; Casasola, Viviana; Combes, Françoise; Dallacasa, Daniele; Davies, Richard; García-Bernete, Ismael; García-Lorenzo, Begoña; Hermosa Muñoz, L.; Peralta de Arriba, L.; Pereira Santaella, Miguel; Pozzi, Francesca; Ramos Almeida, Cristina; Shimizu, Thomas Taro; Vallini, Livia; Bellocchi, Enrica; González-Martín, Omaira; Hicks, Erin K.S.; Hönig, Sebastian; Labiano, Alvaro; Levenson, Nancy A.; Ricci, Claudio; Rosario, David J.; Ministerio de Ciencia e Innovación (MICINN); Universidad Nacional Autónoma de México (UNAM); Science and Technology Facilities Council (STFC); Ministero dell\u2019Istruzione, dell\u2019Università e della Ricerca (MIUR); European Commission (EC); Fondo Nacional de Desarrollo Científico y Tecnológico (FONDECYT); Istituto Nazionale di Astrofisica (INAF); National Aeronautics and Space Administration (NASA)
We present new optical GTC/MEGARA seeing-limited (0.9″) integral-field observations of NGC 5506, together with ALMA observations of the CO(3 - 2) transition at a 0.2″ ( ~25 pc) resolution. NGC 5506 is a luminous (bolometric luminosity of ~1044 erg s-1) nearby (26 Mpc) Seyfert galaxy, part of the Galaxy Activity, Torus, and Outflow Survey (GATOS). We modelled the CO(3 - 2) kinematics with 3DBAROLO, revealing a rotating and outflowing cold gas ring within the central 1.2 kpc. We derived an integrated cold molecular gas mass outflow rate for the ring of ~8 M⊙ yr-1. We fitted the optical emission lines with a maximum of two Gaussian components to separate rotation from non-circular motions. We detected high [OIII]λ5007 projected velocities (up to ~1000 km s-1) at the active galactic nucleus (AGN) position, decreasing with radius to an average ~330 km s-1 around ~350 pc. We also modelled the [OIII] gas kinematics with a non-parametric method, estimating the ionisation parameter and electron density in every spaxel, from which we derived an ionised mass outflow rate of 0.076 M⊙ yr-1 within the central 1.2 kpc. Regions of high CO(3 - 2) velocity dispersion, extending to projected distances of ~350 pc from the AGN, appear to be the result from the interaction of the AGN wind with molecular gas in the galaxy's disc. Additionally, we find the ionised outflow to spatially correlate with radio and soft X-ray emission in the central kiloparsec. We conclude that the effects of AGN feedback in NGC 5506 manifest as a large-scale ionised wind interacting with the molecular disc, resulting in outflows extending to radial distances of 610 pc.
Acceso Abierto
Reionization and the ISM/Stellar Origins with JWST and ALMA (RIOJA): The Core of the Highest-redshift Galaxy Overdensity at z = 7.88 Confirmed by NIRSpec/JWST
(American Astronomical Society, 2023-09-01) Hashimoto, T., T.; Álvarez-Márquez, J., J.; Fudamoto, Y.; Colina, L.; Inoue, A. K.; Nakazato, Y.; Ceverino, D.; Yoshida, N.; Costantin, L.; Sugahara, Y.; Gómez Crespo, A.; Blanco-Prieto, C.; Mawatari, K.; Arribas, Santiago; Marques-Chaves, R.; González, E. M.; Bakx, T. J.L.C.; Hagimoto, M.; Hashigaya, T.; Matsuo, H.; Tamura, Y.; Usui, M.; Ren, Y. W.; Japan Society for the Promotion of Science (KAKENHI); Ministerio de Ciencia e Innovación (MICINN); Ministry of Education, Science, Sports and Culture (MEXT); National Astronomical Observatory of Japan (NAOJ); Comunidad de Madrid; The European Space Agency (ESA)
The protoclusters in the epoch of reionization, traced by galaxy overdensity regions, are ideal laboratories for studying the process of stellar assembly and cosmic reionization. We present the spectroscopic confirmation of the core of the most distant protocluster at z = 7.88, A2744-z7p9OD, with the James Webb Space Telescope NIRSpec integral field unit spectroscopy. The core region includes as many as four galaxies detected in [O iii] 4960 and 5008 Å in a small area of ∼3″ × 3″, corresponding to ∼11 × 11 kpc, after the lensing magnification correction. Three member galaxies are also tentatively detected in dust continuum in Atacama Large Millimeter/submillimeter Array Band 6, which is consistent with their red ultraviolet continuum slopes, β ∼ −1.3. The member galaxies have stellar masses in the range of log(M */M ⊙) ∼7.6-9.2 and star formation rates of ∼3-50 M ⊙ yr−1, showing a diversity in their properties. FirstLight cosmological simulations reproduce the physical properties of the member galaxies including the stellar mass, [O iii] luminosity, and dust-to-stellar mass ratio, and predict that the member galaxies are on the verge of merging in a few to several tens of Myr to become a large galaxy with M * ∼ 6 × 109 M ⊙. The presence of a multiple merger and evolved galaxies in the core region of A2744-z7p9OD indicates that environmental effects are already at work 650 Myr after the Big Bang.
Restringido
Accelerated quenching and chemical enhancement of massive galaxies in a z ≈ 4 gas-rich halo
(Nature Astronomy, 2025-07-21) Pérez-González, Pablo G.; D'Eugenio, Francesco; Rodriguez Del Pino, Bruno; Perna, Michele; Übler, Hannah; Maiolino, Roberto; Arribas, Santiago; Cresci, Giovanni; Lamperti, Isabella; Bunker, Andrew J.; Carniani, Stefano; Willott, Chris J.; Böker, Torsten; Parlanti, Eleonora; Scholtz, Jan; Venturi, Giacomo; Barro, Guillermo; Costantin, Luca; Martin-Navarro, Ignacio; Dunlop, James S.; Magee, Daniel; Ministerio de Ciencia e Innovación (MICINN); Agencia Estatal de Investigación (España); European Commission; Science and Technology Facilities Council (STFC); European Research Council (ERC); Istituto Nazionale di Astrofisica (INAF); Fundación La Caixa
Stars in galaxies form when baryons radiatively cool down and fall into gravitational wells whose mass is dominated by dark matter. Eventually, star formation quenches as gas is depleted and/or perturbed by feedback processes, no longer being able to collapse and condense. We report the first spatially resolved spectroscopic observations, using the JWST/NIRSpec IFU, of a massive, completely quiescent galaxy (Jekyll) and its neighborhood at $z=3.714$, when the Universe age was 10% of today's. Jekyll resides in a massive dark matter halo (with mass M$_\mathrm{DM}>10^{12}$ M$_\odot$) and forms a galaxy pair with Hyde, which shows very intense dust-enshrouded star formation (star formation rate $\sim300$ M$_\odot$yr$^{-1}$). We find large amounts of kinematically perturbed ionized and neutral gas in the circumgalactic medium around the pair. Despite this large gas reservoir, Jekyll, which formed $10^{11}$ M$_\odot$ in stars and chemically enriched early (first billion years of the Universe) and quickly (200-300 Myr), has remained quiescent for over 500 Myr. The properties of the gas found around the two galaxies are consistent with intense, AGN-induced photoionization, or intense shocks. However, with the current data no obscured or unobscured AGN is detected in the central galaxy (Jekyll) nor in the very active and dust rich star-forming galaxy (Hyde).
Acceso Abierto
A fast-rotator post-starburst galaxy quenched by supermassive black-hole feedback at z = 3
(Springer Nature, 2024-09-16) D’Eugenio, Francesco; Pérez-González, Pablo G., E. M.; Maiolino, Roberto; Scholtz, Jan; Perna, Michele; Circosta, Chiara; Übler, Hannah; Arribas, Santiago; Böker, Torsten; Bunker, Andrew J.; Carniani, Stefano; Charlot, Stephane; Chevallard, Jacopo; Cresci, Giovanni; Curtis-Lake, Emma; Jones, Gareth C.; Kumari, Nimisha; Lamperti, Isabella; Looser, Tobias J.; Parlanti, Eleonora; Rix, Hans Walter; Robertson, Brant; Rodriguez Del Pino, Bruno; Tacchella, Sandro; Venturi, Giacomo; Willott, Chris J.; European Research Council (ERC); Ministerio de Ciencia e Innovación (MICINN); Comunidad De Madrid; Agencia Estatal de Investigación (España); Istituto Nazionale di Astrofisica (INAF); Arizona State University (ASU); State University of Santa Cruz (UESC); National Science Foundation (NSF)
The most massive galaxies in the Universe stopped forming stars due to the time-integrated feedback from central supermassive black holes (SMBHs). However, the exact quenching mechanism is not yet understood, because local massive galaxies were quenched billions of years ago. Here we present JWST/NIRSpec integral-field spectroscopy observations of GS-10578, a massive, quiescent galaxy at redshift z = 3.064 ± 0.002. From its spectrum, we measure a stellar mass M⋆ = 1.6 ± 0.2 × 1011 M⊙ and a dynamical mass Mdyn = 2.0 ± 0.5 × 1011 M⊙. Half of its stellar mass formed at z = 3.7–4.6, and the system is now quiescent, with a current star-formation rate of less than 19 M⊙ yr−1. We detect ionized- and neutral-gas outflows traced by [O iii] emission and Na i absorption, with mass outflow rates 0.14–2.9 and 30–100 M⊙ yr−1, respectively. Outflow velocities reach vout ≈ 1,000 km s−1, comparable to the galaxy escape velocity. GS-10578 hosts an active galactic nucleus, evidence that these outflows are due to SMBH feedback. The neutral outflow rate is higher than the star-formation rate. Hence, this is direct evidence for ejective SMBH feedback, with a mass loading capable of interrupting star formation by rapidly removing its fuel. Stellar kinematics show ordered rotation, with spin parameter λRe=0.62±0.07, meaning GS-10578 is rotation-supported. This study presents direct evidence for ejective active galactic nucleus feedback in a massive, recently quenched galaxy, thus helping to clarify how SMBHs quench their hosts. The high value of λRe implies that quenching can occur without destroying the stellar disk.
Restringido
Detection of the elusive dangling OH ice features at ~2.7 μm in Chamaeleon I with JWST NIRCam
(Nature Publishing Group, 2024-09-01) Noble, Jennifer; Fraser, Helen; Smith, Z. L.; Dartois, E.; Boogert, A. C. A.; Cuppen, Herma; Dickinson, Hugh J.; Dulieu, F.; Egami, E.; Erkal, Jessica; Giuliano, B. M.; Husquinet, Basile; Lamberts, T.; Maté, B.; McClure, Melissa; Palumbo, M. E.; Shimonishi, T.; Sun, F.; Bergner, Jennifer; Brown, Wendy; Caselli, P.; Congiu, E.; Drozdovskaya, Maria Nikolayevna; Herrero, V. J.; Ioppolo, Sergio; Jimenez-Serra, Izaskun; Linnartz, Harold; Melnick, G. J.; McGuire, Brett; Oberg, Karin; Perotti, G.; Qasim, D.; Rocha, Will Robson Monteiro; Urso, Riccardo Giovanni
Ascertaining the morphology and composition of the icy mantles covering dust grains in dense, cold regions of the interstellar medium is essential to developing accurate astrochemical models, determining conditions for ice formation, constraining chemical interactions in and on icy grains and understanding how ices withstand space radiation. The widely observed infrared spectroscopic signature of H2O ice at ~3 μm discriminates crystalline from amorphous structures in interstellar ices. Weaker bands seen only in laboratory ice spectra at ~2.7 μm, termed ‘dangling OH’ (dOH), are attributed to water molecules not fully bound to neighbouring water molecules and are often considered as tracing the degree of ice compaction. We exploit the high sensitivity of JWST NIRCam to detect two dOH features at 2.703 and 2.753 μm along multiple lines of sight probing the dense cloud Chamaeleon I, attributing these signatures to unbound dOH in cold water ice and dOH in interaction with other molecular species. These detections open a path to using the dOH features as tracers of the formation, composition, morphology and evolution of icy grains during the star and planet formation process.
Acceso Abierto
Rapid SARS-CoV-2 sensing through oxygen reduction reaction catalysed by Au@Pt/Au core@shell nanoparticles
(Elsevier, 2024-12-01) Martínez-Periñán, Emiliano; Palomares-Albarrán, María; Toyos-Rodríguez, Celia; Mateo Marti, Eva; Pariente, Félix; Escosura-Muñiz, Alfredo de la; Gutiérrez-Sánchez, Cristina; Revenga-Parra, Mónica; Lorenzo, Encarnación; Agencia Estatal de Investigación (España); Ministerio de Ciencia e Innovación (MICINN); Comunidad de Madrid
The development of rapid, accurate, sensitive, and low-cost diagnostic methods for COVID-19 detection in real-time is the unique way to control infection sources and monitor illness progression. In this work, we propose an electrochemical biosensor for the rapid and accuracy diagnosis of COVID-19, through the determination of ORF1ab specific sequence. The biosensor is based on the immobilization of a thiolated sequence partially complementary (domain 1) to ORF1ab on gold screen-printed electrodes and the use of bifunctional Au@Pt/Au core@shell nanoparticles modified with a second thiolated sequence partially complementary to ORF1ab (domain 2) as electrochemical indicator of the hybridization of DNA sequences. The synthesized Au@Pt/Au nanoparticles consist of an Au core, a shell of Pt (Au@Pt NPs), that provides an excellent electrocatalytic activity toward the oxygen reduction reaction (ORR) even after formation of hybrid biomaterials by modification, through the Au protuberances growth on the NPs surface, with an oligonucleotide with recognition ability. The ORR electrochemical activity, enhanced by the label element (Au@Pt/Au NPs), has been employed, for the first time, as indicator of the hybridization event. Based on this strategy, target sequences of the SARS-CoV-2 virus have been detected with a detection limit of 32 pM. The selectivity of the biosensor was confirmed by analysing ORF1ab sequence in the presence of DNA sequences from other viruses. The biosensor has been successfully applied to the direct detection of the virus in non-amplified samples of nasopharyngeal swabs from infected and non-infected patients. Results compare well with those obtained through RT-qPCR but our method is more rapid since does not need any amplification process.
Acceso Abierto
PDRs4All VIII: Mid-IR emission line inventory of the Orion Bar
(EDP Sciences, 2024-04-04) Van De Putte, Dries; Meshaka, Raphael; Trahin, Boris; Habart, Emilie; Peeters, Els; Berné, Olivier; Alarcón, Felipe; Canin, Amélie; Chown, Ryan; Schroetter, Llane; Sidhu, Ameek; Boersma, Christiaan; Bron, Emeric; Dartois, Emmanuel; Goicoechea, Javier R.; Gordon, Karl D.; Onaka, Takashi; Tielens, Alexander G. G. M.; Verstraete, Laurent; Wolfire, Mark G.; Abergel, Alain; Bergin, Edwin A.; Bernard-Salas, Jeronimo; Cami, Jan; Cuadrado, Sara; Dicken, Daniel; Elyajouri, Meriem; Fuente, Asuncion; Joblin, Christine; Baria, Khan; Lacinbala, Ozan; Languignon, David; Le Gal, Romane; Maragkoudakis, Alexandros; Okada, Yoko; Pasquini, Sofia; Pound, Marc W.; Robberto, Massimo; Röllig, Markus; Schefter, Bethany; Schirmer, Thiébaut; Tabone, Benoit; Vicente, Sílvia; Zannese, Marion; Colgan, Sean W. J.; He, Jinhua; Rouillé, Gaël; Togi, Aditya; Aleman, Isabel; Auchettl, Rebecca; Baratta, Giuseppe Antonio; Bejaoui, Salma; Bera, Partha P.; Black, John H.; Boulanger, Francois; Bouwman, Jordy; Brandl, Bernhard; Brechignac, Philippe; Brünken, Sandra; Buragohain, Mridusmita; Burkhardt, Andrew; Candian, Alessandra; Cazaux, Stéphanie; Cernicharo, J.; Chabot, Marin; Chakraborty, Shubhadip; Champion, Jason; Cooke, Ilsa R.; Coutens, Audrey; Cox, Nick L. J.; Demyk, Karine; Donovan Meyer, Jennifer; Foschino, Sacha; García-Lario, Pedro; Gerin, Maryvonne; Gottlieb, Carl A.; Guillard, Pierre; Gusdorf, Antoine; Hartigan, Patrick; Herbst, Eric; Hornekaer, Liv; Issa, Lina; Jäger, Cornelia; Janot-Pacheco, Eduardo; Kannavou, Olga; Kaufman, Michael; Kemper, Francisca ; Kendrew, Sarah; Kirsanova, Maria S. ; Klaassen, Pamela; Kwok, Sun; Labiano, Alvaro; Lai, Thomas S.-Y.; Le Floch, Bertrand; Le Petit, Franck; Li, Aigen; Linz, Hendrik; Mackie, Cameron J.; Madden, Suzanne C.; Mascetti, Joëlle; McGuire, Brett A.; Merino, Pablo; Micelotta, Elisabetta R.; MorseJon A. ,; Mulas, Giacomo; Neelamkodan, Naslim; Ohsawa, Ryou; Omont, Alain; Paladini, Roberta; Palumbo, Maria Elisabetta; Pathak, Amit; Pendleton, Yvonne J.; Petrignani, Annemieke; Pino, Thomas; Puga, Elena; Rangwala, Naseem; Rapacioli, Mathias; Rho, Jeonghee; Ricca, Alessandra; Roman-Duval, Julia; Roser, Joseph; Roueff, Evelyne; Salama, Farid; Sales, Dinalva A.; Sandstrom, Karin; Sarre, Peter; Sciamma-O’Brien, Ella; Sellgren, Kris; Shenoy, Sachindev S.; Teyssier, David; Thomas, Richard D.; Witt, Adolf N.; Wootten, Alwyn; Ysard, Nathalie; Zettergren, Henning; Zhang, Yong; Zhang, Ziwei E.; Zhen, Junfeng; Chinese Academy of Sciences (CAS); Space Telescope Science Institute (STScI); Science and Engineering Research Board (SERB); Ministerio de Ciencia e Innovación (MICINN); Japan Society for the Promotion of Science (JSPS); European Commission (EC); Deutsche Forschungsgemeinschaft (DFG); Ames Research Center, NASA (ARC); Banaras Hindu University (BHU)
Context. Mid-infrared emission features are important probes of the properties of ionized gas and hot or warm molecular gas, which are difficult to probe at other wavelengths. The Orion Bar photodissociation region (PDR) is a bright, nearby, and frequently studied target containing large amounts of gas under these conditions. Under the “PDRs4All” Early Release Science Program for JWST, a part of the Orion Bar was observed with MIRI integral field unit (IFU) spectroscopy, and these high-sensitivity IR spectroscopic images of very high angular resolution (0.2″) provide a rich observational inventory of the mid-infrared (MIR) emission lines, while resolving the H II region, the ionization front, and multiple dissociation fronts. Aims. We list, identify, and measure the most prominent gas emission lines in the Orion Bar using the new MIRI IFU data. An initial analysis summarizes the physical conditions of the gas and demonstrates the potential of these new data and future IFU observations with JWST. Methods. The MIRI IFU mosaic spatially resolves the substructure of the PDR, its footprint cutting perpendicularly across the ionization front and three dissociation fronts. We performed an up-to-date data reduction, and extracted five spectra that represent the ionized, atomic, and molecular gas layers. We identified the observed lines through a comparison with theoretical line lists derived from atomic data and simulated PDR models. The identified species and transitions are summarized in the main table of this work, with measurements of the line intensities and central wavelengths. Results. We identified around 100 lines and report an additional 18 lines that remain unidentified. The majority consists of H I recombination lines arising from the ionized gas layer bordering the PDR. The H I line ratios are well matched by emissivity coefficients from H recombination theory, but deviate by up to 10% because of contamination by He I lines. We report the observed emission lines of various ionization stages of Ne, P, S, Cl, Ar, Fe, and Ni. We show how the Ne III/Ne II, S IV/S III, and Ar III/Ar II ratios trace the conditions in the ionized layer bordering the PDR, while Fe III/Fe II and Ni III/Ni II exhibit a different behavior, as there are significant contributions to Fe II and Ni II from the neutral PDR gas. We observe the pure-rotational H2 lines in the vibrational ground state from 0–0 S(1) to 0–0 S (8), and in the first vibrationally excited state from 1–1 S (5) to 1–1 S(9). We derive H2 excitation diagrams, and for the three observed dissociation fronts, the rotational excitation can be approximated with one thermal (~700 K) component representative of an average gas temperature, and one nonthermal component (~2700 K) probing the effect of UV pumping. We compare these results to an existing model of the Orion Bar PDR, and find that the predicted excitation matches the data qualitatively, while adjustments to the parameters of the PDR model are required to reproduce the intensity of the 0–0 S (6) to S (8) lines.
Restringido
Model Update and Surface Operation Performance of the MEDA-TIRS Radiometer Onboard NASA’s Mars 2020 Perseverance Rover
(Springer Nature, 2025-07-14) Sebastián Martínez, Eduardo; Martínez, Germán M.; Smith, Michael; Peinado, V.; Mora Sotomayor, L.; Vicente Retortillo, Álvaro; Rodríguez Manfredi, J. A.; Ministerio de Economía y Competitividad (MINECO); Ministerio de Ciencia e Innovación (MICINN); Agencia Estatal de Investigación (AEI); National Aeronautics and Space Administration (NASA); Instituto Nacional de Técnica Aeroespacial (España); Centro de Astrobiología del Instituto Nacional de Técnica Aeroespacial y CSIC, MDM-2017-0737
We describe new updates in the data retrieval process of the Mars Environmental Dynamics Analyzer Thermal-InfraRed Sensor (MEDA-TIRS) onboard NASA’s Mars 2020 Perseverance rover and analyze its performance under these new updates for the first 700 sols of this mission. The primary goal of these updates is to reduce the uncertainty in each of the quantities measured by TIRS, thereby improving its performance in measuring atmospheric and ground temperature, reflected shortwave solar radiation, and the upwelling and downwelling longwave irradiances across the entire spectrum. Our updates include results from new modeling efforts and tests conducted during the cruise and operational phase on Mars to characterize the electronic conditioning system and to calculate new noise and offset values. Based on the annual degradation rates of the TIRS channel detectors due to dust deposition, we compare projected values of resolution and accuracy to pre-flight requirements. These projections are useful for estimating the radiometer’s lifetime and for using its data in the context of the future Mars Sample Return and other future mission.
Acceso Abierto
Strong parameter hierarchy in the interstellar phosphorus chemical network
(Frontiers in Bioscience Publications, 2025-07-30) Marina, Fernández-Ruz; Jimenez-Serra, Izaskun; Castro, Mario; Ruiz-Bermejo, Marta; Aguirre, Jacobo; European Research Council (ERC); Ministerio de Ciencia e Innovación (MICINN); Consejo Superior de Investigaciones Científicas (CSIC)
Phosphorus-bearing molecules are fundamental for life on Earth, yet their astrochemical origins remain poorly understood. Their formation in the interstellar medium has been challenging to elucidate due to limited spectroscopic detections and the reliance on theoretical models that depend on numerous kinetic parameters whose values are very uncertain. Multi-parameter models often suffer from “sloppiness”, where many parameter combinations exhibit negligible influence on model outcomes, while a few dominate system behavior. In this study, we introduce the Fisher Information Spectral Reduction (FISR) algorithm, a novel and computationally efficient method to reduce the complexity of such sloppy models. Our approach exposes the strong parameter hierarchy governing these systems by identifying and eliminating parameters associated with insensitive directions in the parameter space. Applying this methodology to the phosphorus astrochemistry network, we reduce the number of reaction rate coefficients from 14 to 3, pinpointing the key reactions and kinetic parameters responsible for forming PO and PN, the main phosphorus-bearing molecules typically detected in interstellar space. The simplified model retains its predictive accuracy, offering deeper insights into the mechanisms driving phosphorus chemistry in the interstellar medium. This methodology is applicable to multi-parameter models of any kind and, specifically in astrochemistry, facilitates the development of simpler, more realistic and interpretable models to effectively guide targeted observational efforts.
Acceso Abierto
Gypsophytes and the use of Martian Gypsum: A review of their potential for agriculture on Mars
(Elsevier BV, 2025-09-25) de Luis, Miguel; López-Pujol, Jordi; Mota, Juan Francisco; Merlo, Encarna; Álvarez-Jiménez, Julio; Aparicio Sánchez, Jose Ignacio; Bartolomé, Carmen; Ormö, Jens; Parro, Laura M.; Ministerio de Ciencia e Innovación (MICINN); Junta de Andalucía
Gypsophytes are plants that thrive on gypsum soils on Earth. They possess some adaptive traits that could constitute pre-adaptations to the conditions for potential cultivation in a controlled habitat on Mars. Martian agriculture should utilize substrates obtained directly from the planet itself. However, the detection of perchlorates in the soil of Mars raises doubts about this possibility. These molecules are distributed globally and in concentrations toxic to both humans and plants. The polar winds may preserve some Martian gypsum outcrops from the effects of perchlorates. If so, using this Martian gypsum as a growing substrate for gypsophytes may be a viable option. In the medium term, implementing gypsophyte adaptations on staple crops would also be possible using CRISPR-Cas9 and/or other gene-editing technologies. According to the literature reviewed, Gypsophila struthium subsp. struthium shows a high degree of colonization capacity and high resistance to drought. This taxon serves as an ecological facilitator for other species, and its germination appears to be favored by the presence of gypsum. Several experimental results suggest it would be worthwhile to test the cultivation of this and other plants on reliable simulants or Martian gypsum through sample return missions or on a mission that would perform the cultivation on Mars itself.
Acceso Abierto
Ejecta from the DART-produced active asteroid Dimorphos
(Springer Nature, 2023-03-01) Li, Jian Yang; Hirabayashi, Masatoshi; Farnham, Tony; Sunshine, Jessica; Knight, Matthew; Tancredi, Gonzalo; Moreno, Fernando; Murphy, Brian; Opitom, Cyrielle; Chesley, Steve; Scheeres, Daniel; Thomas, Cristina; Fahnestock, Eugene; Cheng, Andrew; Dressel, Linda; Ernst, Carolyn; Ferrari, Fabio; Fitzsimmons, Alan; Leva, Simone; Ivanovski, Stavro; Kareta, Theodore; Kolokolova, Ludmilla; Lister, Tim; Raducan, Sabina; Rivkin, Andrew; Rossi, Alessandro; Soldini, Stefania; Stickle, Angela; Vick, Alison; Vicent, Jean-Baptiste; Weaver, Harold; Bagnulo, Stefano; Bannister, Michele; Cambioni, Saverio; Campo Bagatin, Adriano; Chabot, Nancy; Cremonese, Gabriele; Daly, Terik; Dotto, Elisabetta; Glenar, David; Granvik, Mikael; Hasselmann, Pedro; Herreros, Isabel; Jacobson, Seth; Jutzi, Martín; Kohout, Tomas; La Forgia, Tomas; Lazzarin, Monica; Lin, Zhong Yi; Lolachi, Ramin; Lucchetti, Alice; Makadia, Rahil; Mazzotta Epifani, Elena; Michel, Patrick; Migliorini, Alessandra; Moskovitz, Nicholas; Ormö, Jens; Pajola, Maurizio; Sánchez, Paul; Schwartz, Stephen; Snodgrass, Colin; Steckloff, Jordan; Stubbs, Timothy; Trigo Rodríguez, Josep; Swiss National Science Foundation (SNSF); National Aeronautics and Space Administration (NASA); Agencia Estatal de Investigación (AEI); Agencia Nacional de Investigación e Innovación (ANII); Institute of Geology of the Czech Academy of Sciences; Academy of Finland; Centro de Astrobiología del Instituto Nacional de Técnica Aeroespacial y CSIC, MDM-2017-0737
Some active asteroids have been proposed to be formed as a result of impact events. Because active asteroids are generally discovered by chance only after their tails have fully formed, the process of how impact ejecta evolve into a tail has, to our knowledge, not been directly observed. The Double Asteroid Redirection Test (DART) mission of NASA, in addition to having successfully changed the orbital period of Dimorphos, demonstrated the activation process of an asteroid resulting from an impact under precisely known conditions. Here we report the observations of the DART impact ejecta with the Hubble Space Telescope from impact time T + 15 min to T + 18.5 days at spatial resolutions of around 2.1 km per pixel. Our observations reveal the complex evolution of the ejecta, which are first dominated by the gravitational interaction between the Didymos binary system and the ejected dust and subsequently by solar radiation pressure. The lowest-speed ejecta dispersed through a sustained tail that had a consistent morphology with previously observed asteroid tails thought to be produced by an impact. The evolution of the ejecta after the controlled impact experiment of DART thus provides a framework for understanding the fundamental mechanisms that act on asteroids disrupted by a natural impact.
Acceso Abierto
Morphology of ejecta features from the impact on asteroid Dimorphos
(Nature, 2025-02-14) Ferrari, Fabio; Panicucci, Paolo; Merisio, Gianmario; Pugliatti, Mattia; Li, Jian Yang; Fahnestock, Eugene; Raducan, Sabina; Jutzi, Martín; Soldini, Stefania; Hirabayashi, Masatoshi; Merrill, Colby; Michel, Patrick; Moreno, Fernando; Tancredi, Gonzalo; Sunshine, Jessica; Ormö, Jens; Herreros, Isabel; Agrusa, Harrison; Karatekin, Özgür; Zhang, Yun; Chabot, Nancy; Cheng, Andrew; Richardson, Derek; Rivkin, Andrew; Campo Bagati, Adriano; Farnham, Tony; Ivanovski, Stavro; Lucchetti, Alice; Pajola, Maurizio; Rossi, Alessandro; Scheeres, Daniel; Tusberti, Filippo; National Aeronautics and Space Administration (NASA); European Research Council (ERC); Swiss National Science Foundation (SNSF); Centre National D'Etudes Spatiales (CNES); Agencia Estatal de Investigación (AEI); Agencia Nacional de Investigacíon e Innovacíon (ANII); Consejo Superior de Investigaciones Científicas (CSIC); Agenzia Spaziale Italiana (ASI)
Hypervelocity impacts play a significant role in the evolution of asteroids, causing material to be ejected and partially reaccreted. However, the dynamics and evolution of ejected material in a binary asteroid system have never been observed directly. Observations of Double Asteroid Redirection Test (DART) impact on asteroid Dimorphos have revealed features on a scale of thousands of kilometers, including curved ejecta streams and a tail bifurcation originating from the Didymos system. Here we show that these features result naturally from the dynamical interaction of the ejecta with the binary system and solar radiation pressure. These mechanisms may be used to constrain the orbit of a secondary body, or to investigate the binary nature of an asteroid. Also, they may reveal breakup or fission events in active asteroids, and help determine the asteroid’s properties following an impact event. In the case of DART, our findings suggest that Dimorphos is a very weak, rubble-pile asteroid, with an ejecta mass estimated to be in the range of (1.1-5.5)×107 kg.
Restringido
Effect of Target Layering in Gravity-Dominated Cratering in Nature, Experiments, and Numerical Simulations
(AGU Publishing, 2024-04-26) Ormö, Jens; Raducan, S. D.; Housen, K. R.; Wünnemann, K.; Collins, Gareth; Rossi, Angelo Pio; Melero-Asensio, Irene; Consejo Superior de Investigaciones Científicas (CSIC); Agencia Estatal de Investigación (AEI); European Research Council (ERC); Centro de Astrobiología del Instituto Nacional de Técnica Aeroespacial y CSIC, MDM-2017-0737
Impacts into layered targets may generate “concentric craters” where a wider outer crater in the top layer surrounds a smaller, nested crater in the basement, which itself may be complex or simple. The influence of target on cratering depends on the ratio of target strength to lithostatic stress, which, in turn, is affected by gravity, target density, and crater diameter. When this ratio is large, the crater size is primarily determined by target strength, whereas gravitational forces dominate when the ratio is small. In two-layer targets, strength may dominate in one or both layers, whereby the outer crater develops in the weaker top layer and the nested crater in the stronger substrate. However, large natural craters that should be gravity-dominated in both cover strata and substrate may be concentric, the reasons for which are not yet fully understood. We performed qualitative impact experiments at 10–502 G and 1.8 km/s with the Boeing Corp. Hypervelocity centrifuge gun, and at 1 G and 0.4 km/s with the CAB CSIC-INTA gas gun into layered sand targets of different compositions and grain densities but similar granulometry to analyze gravity-dominated cratering. The results are compared with iSALE-2D numerical simulations and natural craters on Earth and Mars. We show that target layering also affects the excavation process and concentric crater formation in gravity-dominated impacts. The most important factors are the density and internal friction of each target layer, respectively. We propose that this is also valid for natural craters of sizes that should make their formation gravity-dominated.
Acceso Abierto
Successful kinetic impact into an asteroid for planetary defence
(Springer, 2023-03-01) Terik Dalay, Ronald; Ernst, Carolyn; Barnouin, Oliver; Chabot, Nancy; Rivkin, Andrew; Cheng, Andrew; Adams, Elena; Agrusa, Harrison; Abdel, Elisabeth; Alford, Amy; Asphaug, Erik; Atchison, Justin; Badger, Andrew; Baki, Paul; Ballouz, Ronald; Bekker, Dmitriy; Bellerose, Julie; Bhaskaran, Shyam; Buratti, Bonnie; Cambioni, Saverio; Chen, Michelle; Chesley, Steven; Chiu, George; Collins, Gareth; Cox, Matthew; DeCoster, Mallory; Ericksen, Peter; Espiritu, Raymond; Faber, Alan; Farnham, Tony; Ferrari, Fabio; Fletcher, Zachary; Gaskell, Robert; Graninger, Dawn; Haque, Musad; Harrington Duff, Alicia; Hefter, Sarah; Herreros, Isabel; Hirabayashi, Masatoshi; Huang, Philip; Hsieh, Syau Yun; Jacobson, Seth; Jenkins, Stephen; Jensenius, Mark; John, Jeremy; Jutzi, Martin; Kohout, Tomas; Krueger, Timothy; Laipert, Frank; López, Norberto; Luther, Robert; Lucchetti, Alice; Mages, Declan; Marchi, Simone; Martín, Anna; McQuaide, Marie; Michel, Patrick; Moskovitz, Nicholas; Murphy, Ian; Murdoch, Naomi; Naidu, Shantanu; Nair, Hari; Nolan, Michael; Ormö, Jens; Pajola, Maurizio; Palmer, Eric; Peachey, James; Pravec, Petr; Raducan, Sabina; Ramesh, K. T.; Ramirez, Joshua; Reynolds, Edward; Richman, Joshua; Robin, Colas; Rodríguez, Luis; Roufberg, Lew; Rush, Brian; Sawyer, Carolyn; Scheeres, Daniel; Scheirich, Petr; Schwartz, Stephen; Shannon, Matthew; Shapiro, Brett; Shearer, Caitlin; Smith, Eva; Steele, Joshua; Steckloff, Jordan; Stickle, Angela; Sunshine, Jessica; Superfin, Emil; Tarzi, Zahi; Thomas, Cristina; Thomas, Justin; Trigo Rodríguez, Josep M.; Tropf, Teresa; Vaughan, Andrew; Velez, Dianna; Waller, Dany; Wilson, Daniel; Wortman, Kristin; Zhang, Yun; Swiss National Science Foundation (SNSF); European Commission (EC); National Aeronautics and Space Administration (NASA); Centre National d’Etudes Spatiales (CNES); Agencia Estatal de Investigación (AEI); Centro de Astrobiología del Instituto Nacional de Técnica Aeroespacial y CSIC, MDM-2017-0737
Although no known asteroid poses a threat to Earth for at least the next century, the catalogue of near-Earth asteroids is incomplete for objects whose impacts would produce regional devastation. Several approaches have been proposed to potentially prevent an asteroid impact with Earth by deflecting or disrupting an asteroid. A test of kinetic impact technology was identified as the highest-priority space mission related to asteroid mitigation. NASA’s Double Asteroid Redirection Test (DART) mission is a full-scale test of kinetic impact technology. The mission’s target asteroid was Dimorphos, the secondary member of the S-type binary near-Earth asteroid (65803) Didymos. This binary asteroid system was chosen to enable ground-based telescopes to quantify the asteroid deflection caused by the impact of the DART spacecraft. Although past missions have utilized impactors to investigate the properties of small bodies, those earlier missions were not intended to deflect their targets and did not achieve measurable deflections. Here we report the DART spacecraft’s autonomous kinetic impact into Dimorphos and reconstruct the impact event, including the timeline leading to impact, the location and nature of the DART impact site, and the size and shape of Dimorphos. The successful impact of the DART spacecraft with Dimorphos and the resulting change in the orbit of Dimorphos demonstrates that kinetic impactor technology is a viable technique to potentially defend Earth if necessary.
Acceso Abierto
Boulder exhumation and segregation by impacts on rubble-pile asteroids
(Elsevier, 2022-07-21) Ormö, Jens; Raducan, Sabina D.; Jutzi, Martin; Herreros, Isabel; Luther, Robert; Collins, Gareth S.; Wünnemann, Kai; Mora Rueda, Marcos; Hamann, C.; European Commission; Centro de Astrobiología del Instituto Nacional de Técnica Aeroespacial y CSIC, MDM-2017-0737
Small asteroids are often considered to be rubble-pile objects, and such asteroids may be the most likely type of Near Earth Objects (NEOs) to pose a threat to Earth. However, impact cratering on such bodies is complex and not yet understood. We perform three low-velocity (≈ 400 m/s) impact experiments in granular targets with and without projectile-size boulders. We conducted SPH simulations that closely reproduced the impact experiments. Our results suggest that cratering on heterogeneous targets displaces and ejects boulders, rather than fragmenting them, unless directly hit. We also see indications that as long as the energy required to disrupt the boulder is small compared to the kinetic energy of the impact, the disruption of boulders directly hit by the projectile may have minimal effect on the crater size. The presence of boulders within the target causes ejecta curtains with higher ejection angles compared to homogeneous targets. At the same time, there is a segregation of the fine ejecta from the boulders, resulting in boulders landing at larger distances than the surrounding fine grained material. However, boulders located in the target near the maximum extent of the expanding excavation cavity are merely exhumed and distributed radially around the crater rim, forming ring patterns similar to the ones observed on asteroids Itokawa, Ryugu and Bennu. Altogether, on rubble-pile asteroids this process will redistribute boulders and finer-grained material heterogeneously, both areally around the crater and vertically in the regolith. In the context of a kinetic impactor on a rubble-pile asteroid and the DART mission, our results indicate that the presence of boulders will reduce the momentum transfer compared to a homogeneous, fine-grained target.
Acceso Abierto
The Proximal Ejecta Around the Marine-Target Lockne Impact Structure, Sweden
(American Geophysical Union, 2023-07) Sturkell, Erik; Ormö, Jens; Austin Hegardt, Eric; Stockmann, Gabrielle; Meland, Erik; Wikström, Torbjörn
Very few impact craters on Earth have preserved proximal ejecta (ejecta blanket), which when present help us to better understand the cratering processes when asteroid hits Earth. The 458 Ma old Lockne impact structure consists of a 7.5-km wide nested crater in the crystalline basement surrounded by an approximately 3-km wide brim developed in the upper sedimentary target. The asteroid struck a marine environment with 500 m sea water, 50-m lithified limestone, and 30 m of Cambrian clay covering a peneplainized crystalline basement. The transient crater that developed in rock and water obtained a “soup-plate” shape and reached about 7 km from the impact crater center, the farthest on the down-range side. The brim of the soup-plate was partially stripped of Ordovician limestone and water before the emplacement of inner impact crater ejecta. Most of the ejecta rest upon the Cambrian clay (today shale). The asteroid struck obliquely from the east, which is reflected in the ejecta distribution. The proximal ejecta field is divided into two crescent-shaped areas to the northwest and southwest of the nested crater and covers 26 km2. Resistivity profiles, mapping, and core drilling show that the thickness of the ejecta masses range between 30 and 50 m with a total volume of about 1 km3. They were not re-worked by the resurge. They represent roughly 26 vol% of the calculated excavated volume of crystalline rocks. Thus, it can be concluded that the Lockne impact crater has a well-preserved ejecta blanket.

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