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arXiv 2020年

作者： Hayakawa, Hisashi Ribeiro, José R. Ebihara, Yusuke Correia, Ana P. Sôma, Mitsuru Institute for Space-Earth Environmental Research Nagoya University Nagoya4648601 Japan Institute for Advanced Research Nagoya University Nagoya4648601 Japan UK Solar System Data Centre Space Physics and Operations Division RAL Space Science and Technology Facilities Council Rutherford Appleton Laboratory Harwell Oxford DidcotOxford-shireOX11 0QX United Kingdom Nishina Centre Riken Wako3510198 Japan Escola Secundária Henrique Medina Esposende Av. Dr. Henrique Barros Lima Esposende4740-203 Portugal Research Institute for Sustainable Humanosphere Kyoto University Uji6100011 Japan Unit of Synergetic Studies for Space Kyoto University Kyoto6068306 Japan National Astronomical Observatory of Japan Mitaka1818588 Japan

The importance of the investigation of magnetic superstorms is not limited to academic interest, because these superstorms can cause catastrophic impact on the modern civilisation due to our increasing dependency on technological infrastructure. In this context, the Carrington storm in September 1859 is considered as a benchmark of observational history owing to its magnetic disturbance and equatorial extent of the auroral oval. So far, several recent auroral reports at that time have been published but those reports are mainly derived from the Northern Hemisphere. In this study, we analyse datable auroral reports from South America and its vicinity, assess the auroral extent using philological and astrometric approaches, identify the auroral visibility at − 17.3° magnetic latitude and further poleward and reconstruct the equatorial boundary of the auroral oval to be 25.1° ± 0.5° in invariant latitude. Interestingly, brighter and more colourful auroral displays were reported in the South American sector than in the Northern Hemisphere. This north–south asymmetry is presumably associated with variations of their magnetic longitude and the weaker magnetic field over South America compared to the magnetic conjugate point and the increased amount of magnetospheric electron precipitation into the upper atmosphere. These results attest that the magnitude of the Carrington storm indicates that its extent falls within the range of other superstorms, such as those that occurred in May 1921 and February 1872, in terms of the equatorial boundary of the auroral oval. Copyright © 2020, The Authors. All rights reserved.

关键词： Storms

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Influence of Ultraviolet Irradiation on the Deposition of spacecraft Molecular Contamination

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Advances in Astronautics science and technology 2018年第2期1卷 183-190页

作者： Dai, Wei Qiu, Jiawen Shen, Zicai Yang, Yanbin Science and Technology on Reliability and Environmental Engineering Laboratory Beijing Institute of Space Environment Engineering 104 You Yi Street Hai Dian District Beijing 100094 China Institute of Spacecraft System Engineering China Academy of Space Technology 104 You Yi Street Hai Dian District Beijing 100094 China Beijing Institute of Space Environment Engineering 104 You Yi Street Hai Dian District Beijing 100094 China

On the basis of physical process analysis of molecular contamination deposition under ultraviolet irradiation, the model of contamination quantity from organic material is proposed. Then ground experiment is performed on the molecular contamination deposition process irradiated by the ultraviolet using silicon rubber material, and the influence of ultraviolet irradiation on the contamination deposition of spacecraft is studied. It is shown from experimental results that the UV irradiation has a significant enhancement on the deposition of contamination, and this effect increases linearly with the radiation dose, but decreases with the deposition temperature. © 2019, Chinese Society of Astronautics.

关键词： Ground experiment Model fitting Molecular contamination Physical modeling Ultraviolet radiation

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CO2–driven surface changes in the Hapi region on Comet 67P/Churyumov–Gerasimenko

arXiv

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arXiv 2022年

作者： Davidsson, Björn J.R. Schloerb, F. Peter Fornasier, Sonia Oklay, Nilda Gutiérrez, Pedro J. Buratti, Bonnie J. Chmielewski, Artur B. Gulkis, Samuel Hofstadter, Mark D. Keller, H. Uwe Sierks, Holger Güttler, Carsten Küppers, Michael Rickman, Hans Choukroun, Mathieu Lee, Seungwon Lellouch, Emmanuel Lethuillier, Anthony Da Deppo, Vania Groussin, Olivier Kührt, Ekkehard Thomas, Nicolas Tubiana, Cecilia El–Maarry, M. Ramy La Forgia, Fiorangela Mottola, Stefano Pajola, Maurizio Jet Propulsion Laboratory California Institute of Technology M/S 183–401 4800 Oak Grove Drive PasadenaCA91109 United States University of Massachusetts Department of Astronomy LGRT–B 847 710 North Pleasant Street AmherstMA01003–9305 United States LESIA Université Paris Cité Observatoire de Paris Université PSL CNRS Sorbonne Université 5 place Jules Janssen Meudon92195 France 1 rue Descartes CEDEX 05 Paris75231 France Berlin Germany Glorieta de la Astronomía s/n. Granada18080 Spain Jet Propulsion Laboratory California Institute of Technology M/S 183–601 4800 Oak Grove Drive PasadenaCA91109 United States Jet Propulsion Laboratory California Institute of Technology M/S 321–655 4800 Oak Grove Drive PasadenaCA91109 United States 200 W Highland Dr. Unit 104 SeattleWA98119 United States Jet Propulsion Laboratory California Institute of Technology 183–301 4800 Oak Grove Drive PasadenaCA91109 United States Technische Universität Braunschweig Mendelssohnstr. 3 Braunschweig38106 Germany Institut für Planetenforschung Asteroiden und Kometen Rutherfordstr. 2 Berlin12489 Germany Max Planck Institute for Solar System Research Justus–von–Liebig–Weg 3 Göttingen37077 Germany Camino Bajo del Castillo s/n Villanueva de la Cañada Madrid28692 Spain Centrum Badań Kosmicznych Polskiej Akademii Nauk Bartycka 18A WarszawaPL–00716 Poland Department of Physics and Astronomy Uppsala University Box 516 UppsalaSE–75120 Sweden Jet Propulsion Laboratory California Institute of Technology M/S 168–200 4800 Oak Grove Drive PasadenaCA91109 United States CNR–IFN Padova Via Trasea 7 Padova35131 Italy Aix Marseille Univ CNRS CNES LAM Marseille France Institute of Optical Sensor Systems Rutherfordstr. 2 Berlin12489 Germany Space Research and Planetology Division Physikalisches Inst. University of Bern Sidlerstrasse 5 BernCH–3012 Switzerland Istituto di Astrofisica e Planetologia Spaziali – IAPS INAF Via del Fosso del Cavaliere 100

Between 2014 December 31 and 2015 March 17, the OSIRIS cameras on Rosetta documented the growth of a 140 m wide and 0.5 m deep depression in the Hapi region on Comet 67P/Churyumov–Gerasimenko. This shallow pit is one of several that later formed elsewhere on the comet, all in smooth terrain that primarily is the result of airfall of coma particles. We have compiled observations of this region in Hapi by the microwave instrument MIRO on Rosetta, acquired during October and November 2014. We use thermophysical and radiative transfer models in order to reproduce the MIRO observations. This allows us to place constraints on the thermal inertia, diffusivity, chemical composition, stratification, extinction coefficients, and scattering properties of the surface material, and how they evolved during the months prior to pit formation. The results are placed in context through long–term comet nucleus evolution modelling. We propose that: 1) MIRO observes signatures that are consistent with a solid–state greenhouse effect in airfall material;2) CO2 ice is sufficiently close to the surface to have a measurable effect on MIRO antenna temperatures, and likely is responsible for the pit formation in Hapi observed by OSIRIS;3) the pressure at the CO2 sublimation front is sufficiently strong to expel dust and water ice outwards, and to compress comet material inwards, thereby causing the near–surface compaction observed by CONSERT, SESAME, and groundbased radar, manifested as the ‘consolidated terrain’ texture observed by OSIRIS. © 2022, CC BY-NC-ND.

关键词： Carbon dioxide

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The enhanced X-ray Timing and Polarimetry mission—eXTP

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science China(Physics,Mechanics & Astronomy) 2019年第2期62卷 3-27页

作者： ShuangNan Zhang Andrea Santangelo Marco Feroci YuPeng Xu FangJun Lu Yong Chen Hua Feng Shu Zhang Sφren Brandt Margarita Hernanz Luca Baldini Enrico Bozzo Riccardo Campana Alessandra De Rosa YongWei Dong Yuri Evangelista Vladimir Karas Norbert Meidinger Aline Meuris Kirpal Nandra Teng Pan Giovanni Pareschi Piotr Orleanski QiuShi Huang Stephane Schanne Giorgia Sironi Daniele Spiga Jiri Svoboda Gianpiero Tagliaferri Christoph Tenzer Andrea Vacchi Silvia Zane Dave Walton ZhanShan Wang Berend Winter Xin Wu Jean J.M.in't Zand Mahdi Ahangarianabhari Giovanni Ambrosi Filippo Ambrosino Marco Barbera Stefano Basso Jörg Bayer Ronaldo Bellazzini Pierluigi Bellutti Bruna Bertucci Giuseppe Bertuccio Giacomo Borghi XueLei Cao Franck Cadoux Francesco Ceraudo TianXiang Chen Yu Peng Chen Jerome Chevenez Marta Civitani Wei Cui WeiWei Cui Thomas Dauser Ettore Del Monte Sergio Di Cosimo Sebastian Diebold Victor Doroshenko Michal Dovciak YuanYuan Du Lorenzo Ducci QingMei Fan Yannick Favre Fabio Fuschino JoséLuis Ga'lvez Min Gao MingYu Ge Olivier Gevin Marco Grassi QuanYing Gu YuDong Gu DaWei Han Bin Hong Wei Hu Long Ji ShuMei Jia WeiChun Jiang Thomas Kennedy Ingo Kreykenbohm Irfan Kuvvetli Claudio Labanti Luca Latronico Gang Li MaoShun Li Xian Li Wei Li ZhengWei Li Olivier Limousin HongWei Liu XiaoJing Liu Bo Lu Tao Luo Daniele Macera Piero Malcovati Adrian Martindale Malgorzata Michalska Bin Meng Massimo Minuti Alfredo Morbidini Fabio Muleri Stephane Paltani Emanuele Perinati Antonino Picciotto Claudio Piemonte JinLu Qu Alexandre Rachevski Irina Rashevskaya Jerome Rodriguez Thomas Schanz ZhengXiang Shen LiZhi Sheng JiangBo Song LiMing Song Carmelo Sgro Liang Sun Ying Tan Phil Uttley Bo Wang DianLong Wang GuoFeng Wang Juan Wang LangPing Wang YuSa Wang Anna L.Watts XiangYang Wen Jörn Wilms ShaoLin Xiong JiaWei Yang Sheng Yang YanJi Yang Nian Yu WenDa Zhang Gianluigi Zampa Nicola Zampa Andrzej A.Zdziarski AiMei Zhang ChengMo Zhang Fan Zhang Long Zhang Tong Zhang Yi Zhang XiaoLi Zhang ZiLiang Zhang BaoSheng Zhao ShiJie Zheng Yu Peng Zhou Key Laboratory for Particle Astrophysics Institute of High Energy PhysicsChinese Academy of Sciences Institut für Astronomie und Astrophysik Eberhard Karls Universität INAF-Istituto di Astrofisica e Planetologia Spaziali INFN-Roma Tor Vergata Via della Ricerca Scientifica 1 Department of Engineering Physics and Center for Astrophysics Tsinghua University DTU Building 327DK-2800 Kongens Institute of Space Sciences 08193 Cerdanyola del Valles Institut d’Estudis Espacials de Catalunya Sezione di Pisa Istituto Nazionale di Fisica NucleareLargo Bruno Pontecorvo3 Department of Astronomy University of Genevachemin d’Ecogia 16 Osservatorio di Astrofisica e Scienza Dello Spazio di Bologna Istituto Nazionale di Astofisica Astronomical Institute Czech Academy of Sciences Max Planck Institute for Extraterrestrial Physics Giessenbachstr.1 CEA Paris-Saclay/IRFU Beijing Institute of Spacecraft System Engineering CAST Osservatorio Astronomico di Brera Istituto Nazionale di Astofisica Space Research Center Polish Academy of Sciences Key Laboratory of Advanced Material Microstructure of Education Ministry of China Institute of Precision Optical EngineeringSchool of Physics Science and EngineeringTongji University Department of Physics and Center for Astrophysics Tsinghua University Universita’degli Studi di Udine Via delle Scienze 206 Mullard Space Science Laboratory University College London Department of Nuclear and Particle Physics University of Geneva SRON Netherlands Institute for Space Research Politecnico di Milano Sezione di Perugia Istituto Nazionale di Fisica Nucleare Dipartimento di Fisica e Chimica Fondazione Bruno Kessler Dr.Karl Remeis-Observatory and Erlangen Centre for Astroparticle Physics Universität Erlangen-Nürnberg University of Pavia Department of ElectronicsInformation and Biomedical Engineering and INFN Pavia Sezione di Torino Istituto Nazionale di Fisica NucleareVia Pietro Giuria1 Department of Physics and Astronomy University of Leicester Sezione di Trieste Istituto Nazionale di Fisica Nucleare

In this paper we present the enhanced X-ray Timing and Polarimetry mission—eXTP. eXTP is a space science mission designed to study fundamental physics under extreme conditions of density, gravity and magnetism. The mission aims at determining the equation of state of matter at supra-nuclear density, measuring effects of QED, and understanding the dynamics of matter in strong-field gravity. In addition to investigating fundamental physics, eXTP will be a very powerful observatory for astrophysics that will provide observations of unprecedented quality on a variety of galactic and extragalactic objects. In particular, its wide field monitoring capabilities will be highly instrumental to detect the electro-magnetic counterparts of gravitational wave *** paper provides a detailed description of:(1) the technological and technical aspects, and the expected performance of the instruments of the scientific payload;(2) the elements and functions of the mission, from the spacecraft to the ground segment.

关键词： X-ray instrumentation X-ray polarimetry X-ray timing space mission:eXTP

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Chasing rainbows and ocean glints: Inner working angle constraints for the Habitable Worlds Observatory

arXiv

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arXiv 2023年

作者： Vaughan, Sophia R. Gebhard, Timothy D. Bott, Kimberly Casewell, Sarah L. Cowan, Nicolas B. Doelman, David S. Kenworthy, Matthew Mazoyer, Johan Millar-Blanchaer, Maxwell A. Trees, Victor J.H. Stam, Daphne M. Absil, Olivier Altinier, Lisa Baudoz, Pierre Belikov, Ruslan Bidot, Alexis Birkby, Jayne L. Bonse, Markus J. Brandl, Bernhard Carlotti, Alexis Choquet, Elodie van Dam, Dirk Desai, Niyati Fogarty, Kevin Fowler, J. van Gorkom, Kyle Gutierrez, Yann Guyon, Olivier Haffert, Sebastiaan Y. Herscovici-Schiller, Olivier Hours, Adrien Juanola-Parramon, Roser Kleisioti, Evangelia König, Lorenzo van Kooten, Maaike Krasteva, Mariya Laginja, Iva Landman, Rico Leboulleux, Lucie Mouillet, David N'Diaye, Mamadou Por, Emiel H. Pueyo, Laurent Snik, Frans Astrophysics Department of Physics University of Oxford Denys Wilkinson Building Keble Road OxfordOX1 3RH United Kingdom Max Planck Institute for Intelligent Systems Max-Planck-Ring 4 Tübingen72076 Germany ETH Zurich Institute for Particle Physics & Astrophysics Wolfgang-Pauli-Str. 27 Zurich8092 Switzerland Department of Earth and Planetary Sciences University of California RiversideCA92521 United States NASA Nexus for Exoplanet System Science Virtual Planetary Laboratory Team SeattleWA98195 United States NASA Nexus for Exoplanet System Science Terrestrial Polarization Team OrlandoFL32826 United States Centre for Exoplanet Research School of Physics and Astronomy University of Leicester University Road LeicesterLE1 7RH United Kingdom Department of Earth & Planetary Sciences Department of Physics McGill University 3600 rue University MontréalQCH3A 2T8 Canada Leiden Observatory Leiden University P.O. Box 9513 Leiden2300 RA Netherlands SRON Netherlands Institute for Space Research Niels Bohrweg 4 Leiden2333 CA Netherlands LESIA Observatoire de Paris Université PSL CNRS Sorbonne Université Université de Paris Meudon92195 France Department of Physics University of California Santa BarbaraCA93106 United States Department of Geoscience & Remote Sensing Delft University of Technology Stevinweg 1 Delft2628 CN Netherlands Utrechtseweg 297 de Bilt 3731 GA Netherlands Delft University of Technology Kluyverweg 1 Delft2629 HS Netherlands STAR Institute Université de Liège Allée du six Août 19c Liège4000 Belgium Aix Marseille Université CNRS CNES LAM Marseille France NASA Ames Research Center Bldg. 245 Moffett Field United States Université Grenoble Alpes CNRS IPAG Grenoble38000 France Department of Astronomy California Institute of Technology PasadenaCA91125 United States Department of Astronomy & Astrophysics University of California Santa CruzCA95064 United States Steward Observatory University of Arizona 933 North C

NASA is engaged in planning for a Habitable Worlds Observatory (HabWorlds), a coronagraphic space mission to detect rocky planets in habitable zones and establish their habitability. Surface liquid water is central to the definition of planetary habitability. Photometric and polarimetric phase curves of starlight reflected by an exoplanet can reveal ocean glint, rainbows and other phenomena caused by scattering by clouds or atmospheric gas. Direct imaging missions are optimised for planets near quadrature, but HabWorlds’ coronagraph may obscure the phase angles where such optical features are strongest. The range of accessible phase angles for a given exoplanet will depend on the planet’s orbital inclination and/or the coronagraph’s inner working angle (IWA). We use a recently-created catalog relevant to HabWorlds of 164 stars to estimate the number of exo-Earths that could be searched for ocean glint, rainbows, and polarization effects due to Rayleigh scattering. We find that the polarimetric Rayleigh scattering peak is accessible in most of the exo-Earth planetary systems. The rainbow due to water clouds at phase angles of ∼20–60◦ would be accessible with HabWorlds for a planet with an Earth equivalent instellation in ∼46 systems, while the ocean glint signature at phase angles of ∼130–170◦ would be accessible in ∼16 systems, assuming an IWA =62 mas (3λ/D). Improving the IWA =41 mas (2λ/D) increases accessibility to rainbows and glints by factors of approximately 2 and 3, respectively. By observing these scattering features, HabWorlds could detect a surface ocean and water cycle, key indicators of habitability. © 2023, CC BY-NC-ND.

关键词： Observatories

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The insight HP3 penetrator (Mole) on mars: Soil properties derived from the penetration attempts and related activities

arXiv

引用

arXiv 2021年

作者： Spohn, Tilman Hudson, T.L. Marteau, E. Golombek, M. Grott, M. Wippermann, T. Ali, K.S. Schmelzbach, C. Kedar, S. Hurst, K. Trebi-Ollennu, A. Ansan, V. Garvin, J. Knollenberg, J. Müller, N. Piqueux, S. Lichtenheldt, R. Krause, C. Fantinati, C. Brinkman, N. Sollberger, D. Delage, P. Vrettos, C. Reershemius, S. Wisniewski, L. Grygorczuk, J. Robertsson, J. Edme, P. Andersson, F. Krömer, O. Lognonné, P. Giardini, D. Smrekar, S.E. Banerdt, W.B. International Space Science Institute Hallerstrasse 6 Bern3012 Switzerland DLR Institute of Planetary Research Rutherfordstr. 2 Berlin12489 Germany DLR Institute of Space Systems Robert-Hooke-Str. 7 Bremen28359 Germany DLR MUSC Space Operations and Astronaut Training Linder Höhe Köln51147 Germany DLR Institute of System Dynamics and Control Münchener Strasse 20 Wessling82234 Germany Jet Propulsion Laboratory California Institute of Technology Oak Grove Drive PasadenaCa91109 United States NASA Goddard Space Flight Center 8800 Greenbelt Road GreenbeltMD20771 United States Astronika Sp. z o.o ul. Bartycka 18 Warszawa00-716 Poland Institute of Geophysics Department of Earth Sciences ETH Zürich ZürichCH-8092 Switzerland Laboratoire de Planétologie et Géodynamique de Nantes Université de Nantes Nantes44322 France École nationale des ponts et chaussées Laboratoire Navier Paris France Department of Civil Engineering University of Kaiserslautern Kaiserslautern Germany Institut du Physique du Globe Paris Paris France Astrium Bremen Germany

The NASA InSight Lander on Mars includes the Heat Flow and Physical Properties Package HP3 to measure the surface heat flow of the planet. The package uses temperature sensors that would have been brought to the target depth of 3–5 m by a small penetrator, nicknamed the mole. The mole requiring friction on its hull to balance remaining recoil from its hammer mechanism did not penetrate to the targeted depth. Instead, by precessing about a point midway along its hull, it carved a 7 cm deep and 5-6 cm wide pit and reached a depth of initially 31 cm. The root cause of the failure - as was determined through an extensive, almost two years long campaign - was a lack of friction in an unexpectedly thick cohesive duricrust. During the campaign – described in detail in this paper – the mole penetrated further aided by friction applied using the scoop at the end of the robotic Instrument Deployment Arm and by direct support by the latter. The mole finally reached a depth of 40 cm, bringing the mole body 1–2 cm below the surface. It reversed its downward motion twice during attempts to provide friction through pressure on the regolith instead of directly with the scoop to the hull. The penetration record of the mole and its thermal sensors were used to measure thermal and mechanical soil parameters such as the penetration resistance of the duricrust of 0.5 - 1.2 MPa and a penetration resistance of a deeper layer (> 30 cm depth) of 5.3 MPa. Applying cone penetration theory, the resistance of the duricrust was used to estimate a cohesion of the latter of 4 - 25 kPa depending on the internal friction angle of the duricrust. Pushing the scoop with its blade into the surface and chopping off a piece of duricrust provided another estimate of the cohesion of 5.8 kPa. The hammerings of the mole were recorded by the seismometer SEIS and the signals could be used to derive a P-wave velocity of 114+40−19 m/s and a S-wave velocity of 60+10−7 m/s (Brinkman et al., 2021) representative of

关键词： Soils

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No thick carbon dioxide atmosphere on the rocky exoplanet TRAPPIST-1c

arXiv

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arXiv 2023年

作者： Zieba, Sebastian Kreidberg, Laura Ducrot, Elsa Gillon, Michaël Morley, Caroline Schaefer, Laura Tamburo, Patrick Koll, Daniel D.B. Lyu, Xintong Acuña, Lorena Agol, Eric Iyer, Aishwarya R. Hu, Renyu Lincowski, Andrew P. Meadows, Victoria S. Selsis, Franck Bolmont, Emeline Mandell, Avi M. Suissa, Gabrielle Max-Planck-Institut für Astronomie Königstuhl 17 HeidelbergD-69117 Germany Leiden Observatory Leiden University Niels Bohrweg 2 Leiden2333CA Netherlands Université Paris-Saclay Université Paris-Cité CEA CNRS AIM France Paris Region Fellow Marie Sklodowska-Curie Action France Astrobiology Research Unit University of Liège Allée du 6 août 19 Liège4000 Belgium Department of Astronomy University of Texas 2515 Speedway AustinTX78712 United States Department of Earth and Planetary Sciences Stanford University StanfordCA United States Department of Astronomy The Institute for Astrophysical Research Boston University 725 Commonwealth Ave. BostonMA02215 United States Department of Atmospheric and Oceanic Sciences Peking University Beijing China Aix-Marseille Université CNRS CNES Institut Origines LAM Marseille France Department of Astronomy Astrobiology Program University of Washington Box 351580 SeattleWA98195 United States NASA Nexus for Exoplanet System Science Virtual Planetary Laboratory Team University of Washington Box 351580 SeattleWA98195 United States School of Earth and Space Exploration Arizona State University 525 E. University Dr. TempeAZ85281 United States NASA FINESST Fellow United States Jet Propulsion Laboratory California Institute of Technology PasadenaCA United States Division of Geological and Planetary Sciences California Institute of Technology PasadenaCA United States Laboratoire d’astrophysique de Bordeaux Univ. Bordeaux CNRS B18N allée Geoffroy Saint-Hilaire Pessac33615 France Observatoire Astronomique Université de Genève chemin Pegasi 51 VersoixCH-1290 Switzerland Centre Vie dans l’Univers Université de Genève Geneva Switzerland NASA Goddard Space Flight Center 8800 Greenbelt Rd GreenbeltMD United States Sellers Exoplanet Environments Collaboration NASA Goddard United States

Seven rocky planets orbit the nearby dwarf star TRAPPIST-1, providing a unique opportunity to search for atmospheres on small planets outside the Solar system [1]. Thanks to the recent launch of the James Webb space Telescope (JWST), possible atmospheric constituents such as carbon dioxide (CO2) are now detectable [2, 3]. Recent JWST observations of the innermost planet TRAPPIST-1 b showed that it is most probably a bare rock without any CO2 in its atmosphere [4]. Here we report the detection of thermal emission from the dayside of TRAPPIST-1 c with the Mid-Infrared Instrument (MIRI) on JWST at 15 µm. We measure a planet-to-star flux ratio of fp/f∗ = 421 ± 94 parts per million (ppm) which corresponds to an inferred dayside brightness temperature of 380 ± 31 K. This high dayside temperature disfavours a thick, CO2-rich atmosphere on the planet. The data rule out cloud-free O2/CO2 mixtures with surface pressures ranging from 10 bar (with 10 ppm CO2) to 0.1 bar (pure CO2). A Venus-analogue atmosphere with sulfuric acid clouds is also disfavoured at 2.6σ confidence. Thinner atmospheres or bare-rock surfaces are consistent with our measured planet-to-star flux ratio. The absence of a thick, CO2-rich atmosphere on TRAPPIST-1 c suggests a relatively volatile-poor formation history, with less than 9.5+7.5−2.3 Earth oceans of water. If all planets in the system formed in the same way, this would indicate a limited reservoir of volatiles for the potentially habitable planets in the system. © 2023, CC BY.

关键词： Carbon dioxide

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Near-real-time monitoring of global CO2 emissions reveals the effects of the COVID-19 pandemic (vol 11, 5172, 2020)

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NATURE COMMUNICATIONS 2020年第1期11卷 5172页

作者： Liu, Zhu Ciais, Philippe Deng, Zhu Lei, Ruixue Davis, Steven J. Feng, Sha Zheng, Bo Cui, Duo Dou, Xinyu Zhu, Biqing Guo, Rui Ke, Piyu Sun, Taochun Lu, Chenxi He, Pan Wang, Yuan Yue, Xu Wang, Yilong Lei, Yadong Zhou, Hao Cai, Zhaonan Wu, Yuhui Guo, Runtao Han, Tingxuan Xue, Jinjun Boucher, Olivier Boucher, Eulalie Chevallier, Frederic Tanaka, Katsumasa Wei, Yiming Zhong, Haiwang Kang, Chongqing Zhang, Ning Chen, Bin Xi, Fengming Liu, Miaomiao Breon, Francois-Marie Lu, Yonglong Zhang, Qiang Guan, Dabo Gong, Peng Kammen, Daniel M. He, Kebin Schellnhuber, Hans Joachim Department of Earth System Science Tsinghua University Beijing China. zhuliu@***. Laboratoire des Sciences du Climat et de l'Environnement LSCE CEA CNRS UVSQ Centre d'Etudes Orme de Merisiers Gif-sur-Yvette France. Department of Earth System Science Tsinghua University Beijing China. Department of Meteorology and Atmospheric Science The Pennsylvania State University University Park PA USA. Department of Earth System Science University of California Irvine 3232 Croul Hall Irvine CA USA. Division of Geological and Planetary Sciences California Institute of Technology Pasadena CA USA. Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control Collaborative Innovation Center of Atmospheric Environment and Equipment Technology School of Environmental Science and Engineering Nanjing University of Information Science & Technology Nanjing China. Key Laboratory of Land Surface Pattern and Simulation Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing China. Climate Change Research Center Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China. Key Laboratory of Middle Atmosphere and Global Environment Observation Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China. School of Environment Tsinghua University Beijing China. School of Mathematical School Tsinghua University Beijing China. Department of Mathematical Sciences Tsinghua University Beijing China. Center of Hubei Cooperative Innovation for Emissions Trading System Wuhan China. Institut Pierre-Simon Laplace Sorbonne Université / CNRS Paris France. Université Paris Dauphine Place du Maréchal de Lattre de Tassigny 75016 Paris France. Center for Energy and Environmental Policy Research Beijing Institute of Technology Beijing China. Department of Electrical Engineering the State Key Lab of Control and Simulation of Power Systems and Generation Equipment Institute for National Governance and G

A Correction to this paper has been published: https://***/10.1038/s41467-020-20254-5

关键词： Climate sciences Atmospheric science Environmental sciences Environmental social sciences

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Bragg's Additivity Rule and Core and Bond model studied by real-time TDDFT electronic stopping simulations: the case of water vapor

arXiv

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arXiv 2021年

作者： Gu, Bin Muñoz-Santiburcio, Daniel Pieve, Fabiana Da Cleri, Fabrizio Artacho, Emilio Kohanoff, Jorge Department of Physics Nanjing University of Information Science and Technology Nanjing210044 China Atomistic Simulation Centre Queen's University Belfast BelfastBT71NN United Kingdom CIC Nanogune BRTA Tolosa Hiribidea 76 San Sebastian20018 Spain Royal Belgian Institute for Space Aeronomy Av Circulaire 3 Brussels1180 Belgium University of Lille CNRS UMR8520 IEMN Institut d'Electronique Microélectronique et Nanotechnologie LilleF-59000 France Ikerbasque Basque Foundation for Science Bilbao48011 Spain Donostia International Physics Center DIPC Paseo Manuel de Lardizabal 4 San Sebastian20018 Spain Theory of Condensed Matter Cavendish Laboratory University of Cambridge J. J. Thomson Ave CambridgeCB3 0HE United Kingdom Instituto de Fusión Nuclear "Guillermo Velarde" Universidad Politécnica de Madrid c/José Gutierrez Abascal 2 Madrid28006 Spain

The electronic stopping power (Se) of water vapor (H2O), hydrogen (H2) and oxygen (O2) gases for protons in a broad range of energies, centered in the Bragg peak, was calculated using real-time time-dependent density functional theory (rt-TDDFT) simulations with Gaussian basis sets. This was done for a kinetic energy of incident protons (Ek) ranging from 1.56 keV/amu to 1.6 MeV/amu. Se was calculated as the average over geometrically pre-sampled short ion trajectories. The average Se(Ek) values were found to rapidly converge with 25-30 pre-sampled, 2 nm-long ion trajectories. The rt-TDDFT Se(Ek) curves were compared to experimental and SRIM data, and used to validate the Bragg's Additivity Rule (BAR). Discrepancies were analyzed in terms of basis set effects and omitted nuclear stopping at low energies. At variance with SRIM, we found that BAR is applicable to our rt-TDDFT simulations of 2H2 + O2 → 2H2O without scaling for Ek > 40 keV/amu. The hydrogen and oxygen Core and Bond (CAB) contributions to electronic stopping were calculated and found to be slightly smaller than SRIM values as a result of a red-shift in our rt-TDDFT Se(Ek) curves and a re-distribution of weights due to some bond contributions being neglected in SRIM. Copyright © 2021, The Authors. All rights reserved.

关键词： Water vapor

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First unambiguous detection of ammonia in the atmosphere of a planetary mass companion with JWST/MIRI coronagraphs

arXiv

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arXiv 2024年

作者： Mâlin, Mathilde Boccaletti, Anthony Perrot, Clément Baudoz, Pierre Rouan, Daniel Lagage, Pierre-Olivier Waters, Rens Güdel, Manuel Henning, Thomas Vandenbussche, Bart Absil, Olivier Barrado, David Charnay, Benjamin Choquet, Elodie Cossou, Christophe Danielski, Camilla Decin, Leen Glauser, Adrian M. Pye, John Olofsson, Goran Glasse, Alistair Patapis, Polychronis Royer, Pierre Scheithauer, Silvia Serabyn, Eugene Tremblin, Pascal Whiteford, Niall van Dishoeck, Ewine F. Ostlin, Göran Ray, Tom P. Wright, Gillian Department of Physics & Astronomy Johns Hopkins University 3400 N. Charles Street BaltimoreMD21218 United States Space Telescope Science Institute 3700 San Martin Drive BaltimoreMD21218 United States LIRA Observatoire de Paris Université PSL Sorbonne Université Université Paris Cité CY Cergy Paris Université CNRS Meudon92190 France Université Paris-Saclay Université Paris Cité CEA CNRS AIM Gif-sur-Yvette91191 France Department of Astrophysics IMAPP Radboud University PO Box 9010 Nijmegen6500 GL Netherlands HFML FELIX. Radboud University PO box 9010 Nijmegen6500 GL Netherlands SRON Netherlands Institute for Space Research Niels Bohrweg 4 Leiden2333 CA Netherlands Department of Astrophysics University of Vienna Türkenschanzstrasse 17 Vienna1180 Austria ETH Zürich Institute for Particle Physics and Astrophysics Wolfgang-Pauli-Strasse 27 Zürich8093 Switzerland Königstuhl 17 Heidelberg69117 Germany Institute of Astronomy KU Leuven Celestijnenlaan 200D Leuven3001 Belgium STAR Institute Université de Liège Allée du Six Août 19c Liège4000 Belgium CSIC-INTA ESAC Campus Camino Bajo del Castillo s/n Villanueva de la Cañada Madrid28692 Spain Aix Marseille Univ CNRS CNES LAM Marseille France Université Paris-Saclay CEA IRFU Gif-sur-Yvette91191 France INAF - Osservatorio Astrofisico di Arcetri Largo E. Fermi 5 Firenze50125 Italy School of Physics & Astronomy Space Park Leicester University of Leicester 92 Corporation Road LeicesterLE4 5SP United Kingdom Department of Astronomy Stockholm University AlbaNova University Center Stockholm10691 Sweden UK Astronomy Technology Centre Royal Observatory Blackford Hill EdinburghEH9 3HJ United Kingdom Jet Propulsion Laboratory California Institute of Technology 4800 Oak Grove Dr. PasadenaCA91109 United States Université Paris-Saclay UVSQ CNRS CEA Maison de la Simulation Gif-sur-Yvette91191 France Department of Astrophysics American Museum of Natural History New YorkNY1

Context. The newly accessible mid-infrared (MIR) window offered by the James Webb space Telescope (JWST) for exoplanet imaging is expected to provide valuable information to characterize their atmospheres. In particular, coronagraphs on board the JWST Mid-InfraRed instrument (MIRI) are capable of imaging the coldest directly imaged giant planets at the wavelengths where they emit most of their flux. The MIRI coronagraphs have been specially designed to detect the NH3 absorption around 10.5 µm, which has been predicted by atmospheric models and should be detectable for planets colder than 1200 K. Aims. We aim to assess the presence of NH3 while refining the atmospheric parameters of one of the coldest companions detected by directly imaging GJ 504 b. Its mass is still a matter of debate and depending on the host star age estimate, the companion could either be placed in the brown dwarf regime of ∼ 20 MJup or in the young Jovian planet regime of ∼ 4 MJup. Methods. We present an analysis of new MIRI observations, using the coronagraphic filters F1065C, F1140C, and F1550C of the GJ 504 system. We took advantage of previous observations of reference stars to build a library of images and to perform a more efficient subtraction of the stellar diffraction pattern. We used an atmospheric grid from the Exo-REM model to refine the atmospheric parameters by combining archival near-infrared (NIR) photometry with the MIR photometry. Results. We detected the presence of NH3 at 12.5 σ and measured its volume mixing ratio of 10−5.3±0.07 in the atmosphere of GJ 504 b. These results are in line with atmospheric model expectations for a planetary-mass object and observed in brown dwarfs within a similar temperature range. The best-fit model with Exo-REM provides updated values of its atmospheric parameters, yielding a temperature of Teff = 512±10 K and radius of R = 1.08+−00.0403 RJup. Conclusions. These observations demonstrate the capability of MIRI coronagraphs to detect NH3 and to

关键词： space telescopes

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