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  • 1. Engebretson, Mark J.
    et al.
    Kirkevold, Kathryn R.
    Steinmetz, Erik S.
    Pilipenko, Viacheslav A.
    Moldwin, Mark B.
    McCuen, Brett A.
    Clauer, C. R.
    Hartinger, Michael D.
    Coyle, Shane
    Opgenoorth, Hermann J.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysik.
    Schillings, Audrey
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysik.
    Willer, Anna N.
    Edwards, Thom R.
    Boteler, David H.
    Gerrard, Andy J.
    Freeman, Mervyn P.
    Rose, Michael C.
    Interhemispheric Comparisons of Large Nighttime Magnetic Perturbation Events Relevant to GICs2020Ingår i: Journal of Geophysical Research - Space Physics, ISSN 2169-9380, E-ISSN 2169-9402, Vol. 125, nr 8, artikel-id e2020JA028128Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Nearly all studies of impulsive magnetic perturbation events (MPEs) with large magnetic field variability (dB/dt) that can produce dangerous geomagnetically induced currents (GICs) have used data from the Northern Hemisphere. Here we present details of four large‐amplitude MPE events (|ΔBx| > 900 nT and |dB/dt| > 10 nT/s in at least one component) observed between 2015 and 2018 in conjugate high‐latitude regions (65–80° corrected geomagnetic latitude), using magnetometer data from (1) Pangnirtung and Iqaluit in eastern Arctic Canada and the magnetically conjugate South Pole Station in Antarctica and (2) the Greenland West Coast Chain and two magnetically conjugate chains in Antarctica, AAL‐PIP and BAS LPM. From one to three different isolated MPEs localized in corrected geomagnetic latitude were observed during three premidnight events; many were simultaneous within 3 min in both hemispheres. Their conjugate latitudinal amplitude profiles, however, matched qualitatively at best. During an extended postmidnight interval, which we associate with an interval of omega bands, multiple highly localized MPEs occurred independently in time at each station in both hemispheres. These nighttime MPEs occurred under a wide range of geomagnetic conditions, but common to each was a negative interplanetary magnetic field Bz that exhibited at least a modest increase at or near the time of the event. A comparison of perturbation amplitudes to modeled ionospheric conductances in conjugate hemispheres clearly favored a current generator model over a voltage generator model for three of the four events; neither model provided a good fit for the premidnight event that occurred near vernal equinox.

  • 2.
    Engebretson, Mark J.
    et al.
    Augsburg University, MN, Minneapolis, United States.
    Pilipenko, Viacheslav A.
    Augsburg University, MN, Minneapolis, United States; Institute of Physics of the Earth, Moscow, Russian Federation.
    Steinmetz, Erik S.
    Augsburg University, MN, Minneapolis, United States.
    Moldwin, Mark B.
    University of Michigan, MI, Ann Arbor, United States.
    Connors, Martin G.
    Athabasca University, AB, Athabasca, Canada.
    Boteler, David H.
    Natural Resources Canada, ON, Ottawa, Canada.
    Singer, Howard J.
    NOAA Space Weather Prediction Center, CO, Boulder, United States.
    Opgenoorth, Hermann J.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysik.
    Schillings, Audrey
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysik.
    Ohtani, Shin
    JHU/APL, MD, Laurel, United States.
    Gjerloev, Jesper
    JHU/APL, MD, Laurel, United States.
    Russell, Christopher T.
    UCLA Department of Earth Planetary and Space Sciences, CA, Los Angeles, United States.
    Nighttime Magnetic Perturbation Events Observed in Arctic Canada: 3. Occurrence and Amplitude as Functions of Magnetic Latitude, Local Time, and Magnetic Disturbance Indices2021Ingår i: Space Weather: The International Journal of Research and Application, E-ISSN 1542-7390, Vol. 19, nr 3, artikel-id e2020SW002526Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Rapid changes of magnetic fields associated with nighttime magnetic perturbation events (MPEs) with amplitudes |ΔB| of hundreds of nT and 5–10 min duration can induce geomagnetically induced currents (GICs) that can harm technological systems. This study compares the occurrence and amplitude of nighttime MPEs with |dB/dt| ≥ 6 nT/s observed during 2015 and 2017 at five stations in Arctic Canada ranging from 64.7° to 75.2° in corrected geomagnetic latitude (MLAT) as functions of magnetic local time (MLT), the SME (SuperMAG version of AE) and SYM/H magnetic indices, and time delay after substorm onsets. Although most MPEs occurred within 30 min after a substorm onset, ∼10% of those observed at the four lower latitude stations occurred over two hours after the most recent onset. A broad distribution in local time appeared at all five stations between 1700 and 0100 MLT, and a narrower distribution appeared at the lower latitude stations between 0200 and 0700 MLT. There was little or no correlation between MPE amplitude and the SYM/H index; most MPEs at all stations occurred for SYM/H values between −40 and 0 nT. SME index values for MPEs observed >1 h after the most recent substorm onset fell in the lower half of the range of SME values for events during substorms, and dipolarizations in synchronous orbit at GOES 13 during these events were weaker or more often nonexistent. These observations suggest that substorms are neither necessary nor sufficient to cause MPEs, and hence predictions of GICs cannot focus solely on substorms.

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  • 3.
    Hamrin, Maria
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysik.
    Schillings, Audrey
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysik.
    Opgenoorth, Hermann J.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysik.
    Nesbit-Östman, Sara
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysik.
    Krämer, Eva
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysik.
    Araújo, Juan Carlos
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för naturvetenskapernas och matematikens didaktik.
    Baddeley, Lisa
    Department of Arctic Geophysics, University Centre in Svalbard, Longyearbyen, Norway.
    Gunell, Herbert
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysik.
    Pitkänen, Timo
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysik. Institute of Space Sciences, Shandong University, Weihai, China.
    Gjerloev, Jesper
    Johns Hopkins University, Laurel, MD, USA.
    Barnes, R. J.
    Johns Hopkins University, Laurel, MD, USA.
    Space weather disturbances in non-stormy times: occurrence of dB/dt spikes during three solar cycles2023Ingår i: Journal of Geophysical Research - Space Physics, ISSN 2169-9380, E-ISSN 2169-9402, Vol. 128, nr 10, artikel-id e2023JA031804Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Spatio-temporal variations of ionospheric currents cause rapid magnetic field variations at ground level and Geomagnetically Induced Currents (GICs) that can be harmful for human infrastructure. The risk for large excursions in the magnetic field time derivative, “dB/dt spikes”, is known to be high during geomagnetic storms and substorms. However, less is known about the occurrence of spikes during non-stormy times. We use data from ground-based globally covering magnetometers (SuperMAG database) from the years 1985–2021. We investigate the spike occurrence (|dB/dt| > 100 nT/min) as a function of magnetic local time (MLT), magnetic latitude (Mlat), and the solar cycle phases during non-stormy times (−15 nT ≤ SYM-H < 0). We sort our data into substorm (AL < 200 nT) intervals (“SUB”) and less active intervals between consecutive substorms (“nonSUB”). We find that spikes commonly occur in both SUBs and nonSUBs during non-stormy times (3–23 spikes/day), covering 18–12 MLT and 65°–80° Mlat. This also implies a risk for infrastructure damage during non-stormy times, especially when several spikes occur nearby in space and time, possibly causing infrastructure weathering. We find that spikes are more common in the declining phase of the solar cycle, and that the occurrence of SUB spikes propagates from one midnight to one morning hotspot with ∼10 min in MLT for each minute in universal time (UTC). Finally, we discuss causes for the spikes in terms of spatio-temporal variations of ionospheric currents.

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  • 4.
    Lester, Mark
    et al.
    School of Physics and Astronomy, University of Leicester, Leicester, United Kingdom.
    Sanchez-Cano, Beatriz
    School of Physics and Astronomy, University of Leicester, Leicester, United Kingdom.
    Potts, Daniel
    School of Physics and Astronomy, University of Leicester, Leicester, United Kingdom.
    Lillis, Rob
    Space Sciences Laboratory, University of California, CA, Berkeley, United States.
    Cartacci, Marco
    Istituto di Astrofisica e Planetologia Spaziali, Istituto Nazionale di Astrofisica, Rome, Italy.
    Bernardini, Fabrizio
    Istituto di Astrofisica e Planetologia Spaziali, Istituto Nazionale di Astrofisica, Rome, Italy.
    Orosei, Roberto
    Istituto di Radioastronomia, Istituto Nazionale di Astrofisica, Bologna, Italy.
    Perry, Matthew
    Planetary Science Institute, CO, Lakewood, United States.
    Putzig, Nathaniel
    Planetary Science Institute, CO, Lakewood, United States.
    Campbell, Bruce
    Center for Earth and Planetary Studies, Smithsonian Institution, DC, Washington, United States.
    Blelly, Pierre-Louis
    Institut de Recherche en Astrophysique et Planétologie, Toulouse, France.
    Milan, Steve
    School of Physics and Astronomy, University of Leicester, Leicester, United Kingdom.
    Opgenoorth, Hermann J.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysik. School of Physics and Astronomy, University of Leicester, Leicester, United Kingdom.
    Witasse, Olivier
    European Space Agency (ESA), European Space Research and Technology Centre (ESTEC), Noordwijk, Netherlands.
    Redrojo, Elena M. M.
    Valquer Laboratorios, Villaminaya, Spain.
    Russell, Aaron
    Planetary Science Institute, CO, Lakewood, United States.
    The Impact of Energetic Particles on the Martian Ionosphere During a Full Solar Cycle of Radar Observations: Radar Blackouts2022Ingår i: Journal of Geophysical Research - Space Physics, ISSN 2169-9380, E-ISSN 2169-9402, Vol. 127, nr 2, artikel-id e2021JA029535Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We present the first long-term characterization of ionization layers in the lower ionosphere of Mars (below ∼90 km), a region inaccessible to orbital in-situ observations, based on an analysis of radar echo blackouts observed on Mars Express and the Mars Reconnaissance Orbiter from 2006 to 2017. A blackout occurs when the expected surface reflection is partly or totally attenuated for portions of an observation. Enhanced ionization at altitudes of 60–90 km, below the main ionospheric electron density peak, leads to increased absorption of the radar signal, resulting in the blackouts. We find that (a) MARSIS, operating at frequencies between 1.8 and 5 MHz, suffered more blackouts than SHARAD, which has a higher carrier frequency (20 MHz), (b) there is a clear correlation of blackout occurrence with solar cycle, (c) there is no apparent relationship between blackout occurrence and crustal magnetic fields, and (d) blackouts occur during both nightside and dayside observations, although the peak occurrence is deep on the nightside. Analysis of Mars Atmosphere and Volatile EvolutioN Solar Energetic Particle electron counts between 20 and 200 keV demonstrates that these electrons are likely responsible for attenuating the radar signals. We investigate the minimum SEP electron fluxes required to ionize the lower atmosphere and produce measurable attenuation. When both radars experience a blackout, the SEP electron fluxes are at their highest. Based on several case studies, we find that the average SEP spectrum responsible for a blackout is particularly enhanced at its higher energy end, that is, above 70 keV.

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  • 5.
    Lillis, Robert J.
    et al.
    Space Sciences Laboratory, University of California, CA, Berkeley, United States.
    Mitchell, David
    Space Sciences Laboratory, University of California, CA, Berkeley, United States.
    Montabone, Luca
    Space Sciences Institute, CO, Boulder, United States.
    Heavens, Nicholas
    Space Sciences Institute, CO, Boulder, United States.
    Harrison, Tanya
    Planet Federal Inc., DC, Washington, United States.
    Stuurman, Cassie
    Jet Propulsion Laboratory, California Institute of Technology, CA, Pasadena, United States.
    Guzewich, Scott
    NASA Goddard Space Flight Ctr., MD, Greenbelt, United States.
    England, Scott
    Virginia Tech University, VA, Blacksburg, United States.
    Withers, Paul
    Boston University, MA, Boston, United States.
    Chaffin, Mike
    Laboratory for Atmospheric and Space Physics, University of Colorado, CO, Boulder, United States.
    Curry, Shannon
    Space Sciences Laboratory, University of California, CA, Berkeley, United States.
    Ao, Chi
    Jet Propulsion Laboratory, California Institute of Technology, CA, Pasadena, United States.
    Matousek, Steven
    Jet Propulsion Laboratory, California Institute of Technology, CA, Pasadena, United States.
    Barba, Nathan
    Jet Propulsion Laboratory, California Institute of Technology, CA, Pasadena, United States.
    Woolley, Ryan
    Jet Propulsion Laboratory, California Institute of Technology, CA, Pasadena, United States.
    Smith, Isaac
    York University, ON, Toronto, Canada.
    Osinski, Gordon R.
    University of Western Ontario, ON, London, Canada.
    Kleinböhl, Armin
    Jet Propulsion Laboratory, California Institute of Technology, CA, Pasadena, United States.
    Tamppari, Leslie
    Jet Propulsion Laboratory, California Institute of Technology, CA, Pasadena, United States.
    Mischna, Michael
    Jet Propulsion Laboratory, California Institute of Technology, CA, Pasadena, United States.
    Kass, David
    Jet Propulsion Laboratory, California Institute of Technology, CA, Pasadena, United States.
    Smith, Michael
    NASA Goddard Space Flight Ctr., MD, Greenbelt, United States.
    Wolff, Michael
    Space Sciences Institute, CO, Boulder, United States.
    Kahre, Melinda
    NASA Ames Research Ctr., CA, Mountain View, United States.
    Spiga, Aymeric
    Laboratoire de Météorologie Dynamique, IPSL, Paris, France.
    Forget, François
    Laboratoire de Météorologie Dynamique, IPSL, Paris, France.
    Cantor, Bruce
    Malin Space Science Systems, CA, San Diego, United States.
    Deighan, Justin
    Laboratory for Atmospheric and Space Physics, University of Colorado, CO, Boulder, United States.
    Brecht, Amanda
    NASA Ames Research Ctr., CA, Mountain View, United States.
    Bougher, Stephen
    University of Michigan, MI, Ann Arbor, United States.
    Fowler, Christopher M.
    Space Sciences Laboratory, University of California, CA, Berkeley, United States.
    Andrews, David
    Swedish Institute of Space Physics, Uppsala, Sweden.
    Patzold, Martin
    Rheinisches Institut für Umweltforschung, Abt. Planetenforschung, Cologne, Germany.
    Peter, Kerstin
    Rheinisches Institut für Umweltforschung, Abt. Planetenforschung, Cologne, Germany.
    Tellmann, Silvia
    Rheinisches Institut für Umweltforschung, Abt. Planetenforschung, Cologne, Germany.
    Lester, Mark
    School of Physics and Astronomy, University of Leicester, United Kingdom.
    Sánchez-Cano, Beatriz
    School of Physics and Astronomy, University of Leicester, United Kingdom.
    Luhmann, Janet
    Space Sciences Laboratory, University of California, CA, Berkeley, United States.
    Leblanc, François
    Laboratoire Atmosphères, Observations Spatiales, IPSL, Paris, France.
    Halekas, Jasper
    University of Iowa, IA, Iowa City, United States.
    Brain, David
    Laboratory for Atmospheric and Space Physics, University of Colorado, CO, Boulder, United States.
    Fang, Xiaohua
    Laboratory for Atmospheric and Space Physics, University of Colorado, CO, Boulder, United States.
    Espley, Jared
    NASA Goddard Space Flight Ctr., MD, Greenbelt, United States.
    Opgenoorth, Hermann J.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysik.
    Vaisberg, Oleg
    Space Research Institute, Moscow, Russian Federation.
    Hinson, David
    SETI Institute, CA, Mountain View, United States.
    Asmar, Sami
    Jet Propulsion Laboratory, California Institute of Technology, CA, Pasadena, United States.
    Vander Hook, Joshua
    Jet Propulsion Laboratory, California Institute of Technology, CA, Pasadena, United States.
    Karatekin, Ozgur
    Royal Belgian Observatory, Uccle, Belgium.
    Barjatya, Aroh
    Embry Riddle Aeronautical University, FL, Daytona Beach, United States.
    Tripathi, Abhishek
    Space Sciences Laboratory, University of California, CA, Berkeley, United States.
    MOSAIC: A satellite constellation to enable groundbreaking mars climate system science and prepare for human exploration2021Ingår i: Planetary Science Journal, E-ISSN 2632-3338, Vol. 2, nr 5, artikel-id 211Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The Martian climate system has been revealed to rival the complexity of Earth's. Over the last 20 yr, a fragmented and incomplete picture has emerged of its structure and variability; we remain largely ignorant of many of the physical processes driving matter and energy flow between and within Mars' diverse climate domains. Mars Orbiters for Surface, Atmosphere, and Ionosphere Connections (MOSAIC) is a constellation of ten platforms focused on understanding these climate connections, with orbits and instruments tailored to observe the Martian climate system from three complementary perspectives. First, low-circular near-polar Sun-synchronous orbits (a large mothership and three smallsats spaced in local time) enable vertical profiling of wind, aerosols, water, and temperature, as well as mapping of surface and subsurface ice. Second, elliptical orbits sampling all of Mars' plasma regions enable multipoint measurements necessary to understand mass/energy transport and ion-driven escape, also enabling, with the polar orbiters, dense radio occultation coverage. Last, longitudinally spaced areostationary orbits enable synoptic views of the lower atmosphere necessary to understand global and mesoscale dynamics, global views of the hydrogen and oxygen exospheres, and upstream measurements of space weather conditions. MOSAIC will characterize climate system variability diurnally and seasonally, on meso-, regional, and global scales, targeting the shallow subsurface all the way out to the solar wind, making many first-of-their-kind measurements. Importantly, these measurements will also prepare for human exploration and habitation of Mars by providing water resource prospecting, operational forecasting of dust and radiation hazards, and ionospheric communication/positioning disruptions.

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  • 6.
    Liu, William
    et al.
    National Space Science Centre, Chinese Academy of Sciences, Beijing, China.
    Blanc, Michel
    National Space Science Centre, Chinese Academy of Sciences, Beijing, China; University of Toulouse, Toulouse, France.
    Wang, Chi
    National Space Science Centre, Chinese Academy of Sciences, Beijing, China.
    Donavan, Eric
    University of Calgary, Calgary, Canada.
    Foster, John
    MIT Haystack Observatory, MA, Cambridge, United States.
    Lester, Mark
    University of Leicester, Leicester, United Kingdom.
    Opgenoorth, Hermann J.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysik. University of Leicester, Leicester, United Kingdom.
    Ren, Liwen
    National Space Science Centre, Chinese Academy of Sciences, Beijing, China.
    Scientific challenges and instrumentation for the International Meridian Circle Program2021Ingår i: Science China. Earth Sciences, ISSN 1674-7313, E-ISSN 1869-1897, Vol. 64, nr 12, s. 2090-2097Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Earth’s ecosystems and human activities are threatened by a broad spectrum of hazards of major importance for the safety of ground infrastructures, space systems and space flight: solar activity, earthquakes, atmospheric and climatic disturbances, changes in the geomagnetic field, fluctuations of the global electric circuit. Monitoring and understanding these major hazards to better predict and mitigate their effects is one of the greatest scientific and operational challenges of the 21st century. Though diverse, these hazards share one feature in common: they all leave their characteristic imprints on a critical layer of the Earth’s environment: its ionosphere, middle and upper atmosphere (IMUA). The objective of the International Meridian Circle Program (IMCP), a major international program led by the Chines Academy of Sciences (CAS), is to deploy, integrate and operate a global network of research and monitoring instruments to use the IMUA as a screen on which to detect these imprints. In this article, we first show that the geometry required for the IMCP global observation system leads to a deployment of instruments in priority along the 120°E–60°W great meridian circle, which will cover in an optimal way both the dominant geographic and geomagnetic latitude variations, possibly complemented by a second Great Circle along the 30°E–150°W meridians to capture longitude variations. Then, starting from the Chinese Meridian Project (CMP) network and using it as a template, we give a preliminary and promising description of the instruments to be integrated and deployed along the 120°E–60° W great circle running across China, Australia and the Americas.

  • 7.
    Norenius, Linus
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysik.
    Hamrin, Maria
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysik.
    Goncharov, O.
    Faculty of Mathematics and Physics, Charles University, Prague, Czech Republic.
    Gunell, Herbert
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysik.
    Opgenoorth, Hermann J.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysik.
    Pitkänen, Timo
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysik. Space Physics and Astronomy Research Unit, University of Oulu, Oulu, Finland.
    Chong, Ghai Siung
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysik.
    Partamies, N.
    Department of Geophysics, The University Centre in Svalbard, Svalbard, Longyearbyen, Norway; Birkeland Centre for Space Science, Bergen, Norway.
    Baddeley, L.
    Department of Geophysics, The University Centre in Svalbard, Svalbard, Longyearbyen, Norway; Birkeland Centre for Space Science, Bergen, Norway.
    Ground-Based Magnetometer Response to Impacting Magnetosheath Jets2021Ingår i: Journal of Geophysical Research - Space Physics, ISSN 2169-9380, E-ISSN 2169-9402, Vol. 126, nr 8, artikel-id e2021JA029115Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Localized dynamic pressure pulses in the magnetosheath, or jets, have been a popular topic for discussion in recent decades. Studies show that they can propagate through the magnetosheath and impact the magnetopause, possibly showing up as geoeffective elements at ground level. However, questions still remain on how geoeffective they can be. Previous studies have been limited to case studies during few days and with only a handful of events. In this study we have found 65 cases of impacting jets using observations from the Multiscale Magnetospheric mission during 2015–2017. We examine their geoeffectiveness using ground-based magnetometers (GMAGs). From our statistics we find that GMAGs observe responses as fluctuations in the geomagnetic field with amplitudes of 34 nT, frequencies of 1.9 mHz, and damping times of 370 s. Further, the parallel length and the maximum dynamic pressure of the jet dictate the amplitude of the observed GMAG response. Longer and higher pressure jets inducing larger amplitude responses in GMAG horizontal components. The median time required for the signal to be detected by GMAGs is 190 s. We also examine if jets can be harmful for human infrastructure and cannot exclude that such events could exist.

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  • 8.
    Opgenoorth, Hermann J.
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysik. Department of Physics and Astronomy, University of Leicester, LE1 7RH Leicester, UK.
    Wimmer-Schweingruber, Robert F.
    Belehaki, Anna
    Berghmans, David
    Hapgood, Mike
    Hesse, Michael
    Kauristie, Kirsti
    Lester, Mark
    Lilensten, Jean
    Messerotti, Mauro
    Temmer, Manuela
    Assessment and recommendations for a consolidated European approach to space weather - as part of a global space weather effort2019Ingår i: Journal of Space Weather and Space Climate, E-ISSN 2115-7251, Vol. 9, artikel-id A37Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Over the last 10-20 years there has been an ever-increasing international awareness of risks to modern society from adverse and potentially harmful - and in extreme cases even disastrous - space weather events. Many individual countries and even international organisations like the United Nations (UN) have begun to increase their activities in preparing for and mitigating effects of adverse space weather. As in the rest of the world there is also in Europe an urgent need for coordination of Space Weather efforts in individual countries as well as in and among European organisations such as the European Space Agency (ESA) and the European Union (EU). This coordination should not only improve our ability to meet space weather risks, but also enable Europe to contribute to on-going global space weather efforts. While space weather is a global threat, which needs a global response, it also requires tailored regional and trans-regional responses that require coordination at all levels. Commissioned by the European Space Science Committee (ESSC) of the European Science Foundation, the authors - together with ex-officio advice from ESA and the EU - have over two years assessed European activities in the realm of space weather and formulated a set of recommendations to ESA, the EU and their respective member states, about how to prepare Europe for the increasing impact of adverse space weather effects on man-made infrastructure and our society as a whole. We have also analysed parallel international activities worldwide, and we give advice how Europe could incorporate its future activities into a global scheme.

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  • 9. Sanchez-Cano, Beatriz
    et al.
    Lester, Mark
    Witasse, Olivier
    Morgan, David D.
    Opgenoorth, Hermann J.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysik. Radio and Space Plasma Physics Group, Department of Physics and Astronomy, University of Leicester, Leicester, UK.
    Andrews, David J.
    Blelly, Pierre-Louis
    Cowley, Stanley W. H.
    Kopf, Andrew J.
    Leblanc, Francois
    Espley, Jared R.
    Cardesin-Moinelo, Alejandro
    Mars' Ionospheric Interaction With Comet C/2013 A1 Siding Spring's Coma at Their Closest Approach as Seen by Mars Express2020Ingår i: Journal of Geophysical Research - Space Physics, ISSN 2169-9380, E-ISSN 2169-9402, Vol. 125, nr 1, artikel-id e2019JA027344Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    On 19 October 2014, Mars experienced a close encounter with Comet C/2013 A1 Siding Spring. Using data from the Mars Advanced Radar for Subsurface and Ionosphere Sounding (MARSIS) on board Mars Express (MEX), we assess the interaction of the Martian ionosphere with the comet's coma and possibly magnetic tail during the orbit of their closest approach. The topside ionospheric electron density profile is evaluated from the altitude of the peak density of the ionosphere up to the MEX altitude. We find complex and rapid variability in the ionospheric profile along the MEX orbit, not seen even after the impact of a large coronal mass ejection. Before closest approach, large electron density reductions predominate, which could be caused either by comet water damping or comet magnetic field interactions. After closest approach, a substantial electron density rise predominates. Moreover, several extra topside layers are visible along the whole orbit at different altitudes, which could be related to different processes as we discuss.

  • 10.
    Schillings, Audrey
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysik. School of Physics and Astronomy, University of Leicester, Leicester, United Kingdom.
    Palin, L.
    Toulouse, France.
    Opgenoorth, Hermann J.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysik. School of Physics and Astronomy, University of Leicester, Leicester, United Kingdom.
    Hamrin, Maria
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysik.
    Rosenqvist, L.
    Swedish Defence Research Agency, Stockholm, Sweden.
    Gjerloev, J.W.
    JHU/APL, MD, Laurel, United States; Department of Physics and Technology, University of Bergen, Bergen, Norway.
    Juusola, L.
    Finnish Meteorological Institute, Helsinki, Finland.
    Barnes, R.
    JHU/APL, MD, Laurel, United States.
    Distribution and Occurrence Frequency of dB/dt Spikes During Magnetic Storms 1980–20202022Ingår i: Space Weather: The International Journal of Research and Application, E-ISSN 1542-7390, Vol. 20, nr 5, artikel-id e2021SW002953Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The physical magnetospheric cause for geomagnetically induced currents (GICs) are rapid time-varying magnetic fields (dB/dt), which occur mainly during magnetic substorms and storms. When, where and why exactly such rapid dB/dt may occur is insufficiently understood. We investigated all storms since 1980 and analyzed the negative and positive dB/dt spikes (>|500| nT/min) in the north and east component using a worldwide coverage (SuperMAG). Our analysis confirmed the existence of two dB/dt spikes "hotspots" located in the pre-midnight and in the morning magnetic local time sector, independently of the geographic location of the stations. The associated physical phenomena are probably substorm current wedge onsets and westward traveling surges (WTS) in the evening sector, and wave- or vortex-like current flows in the morning sector known as Omega bands. We observed a spatiotemporal evolution of the negative northern dB/dt spikes. The spikes initially occur in the pre-midnight sector, and then develop in time toward the morning sector. This spatiotemporal sequence is correlated with bursts in the AE index, and can be repeated several times throughout a storm. Finally, we investigated the peak value of Dst and AE during the storm period in comparison with the dB/dt spike occurrence frequency, we did not find any correlation. This result implies that a moderate storm with many spikes can be as (or more) dangerous for ground-based infrastructures than a major storm with fewer dB/dt spikes. Our findings regarding the physical causes and characteristics of dB/dt spikes may help to improve the GIC forecast for the affected regions.

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  • 11.
    Schillings, Audrey
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysik. School of Physics and Astronomy, University of Leicester, United Kingdom.
    Palin, Laurianne
    Thales Alenia Space, Toulouse, France.
    Bower, Gemma E.
    School of Physics and Astronomy, University of Leicester, United Kingdom.
    Opgenoorth, Hermann J.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysik. School of Physics and Astronomy, University of Leicester, United Kingdom.
    Milan, Steve E.
    School of Physics and Astronomy, University of Leicester, United Kingdom.
    Kauristie, Kirsti
    Finnish Meteorological Institute, Dynamicum Erik Palménin aukio 1, Helsinki, Finland.
    Juusola, Liisa
    Finnish Meteorological Institute, Dynamicum Erik Palménin aukio 1, Helsinki, Finland.
    Reeves, Geoff D.
    Space Science and Applications Group, Los Alamos National Laboratory, NM, Los Alamos, United States.
    Henderson, Mike G.
    Space Science and Applications Group, Los Alamos National Laboratory, NM, Los Alamos, United States.
    Paxton, Larry J.
    Johns Hopkins University Applied Physics Laboratory, Laurel, United States.
    Lester, Mark
    School of Physics and Astronomy, University of Leicester, United Kingdom.
    Hamrin, Maria
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysik.
    Van De Kamp, Max
    Finnish Meteorological Institute, Dynamicum Erik Palménin aukio 1, Helsinki, Finland.
    Signatures of wedgelets over Fennoscandia during the St Patrick s Day Storm 20152023Ingår i: Journal of Space Weather and Space Climate, E-ISSN 2115-7251, Vol. 13, artikel-id 19Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    During the long main phase of the St Patrick's Day storm on March 17, 2015, we found three separate enhancements of the westward electrojet. These enhancements are observed in the ionospheric equivalent currents computed using geomagnetic data over Fennoscandia. Using data from the IMAGE magnetometer network, we identified localised field-aligned current (FAC) systems superimposed on the pre-existing ionospheric current system. We suggest that these localised current systems are wedgelets and that they can potentially contribute to a larger-scale structure of a substorm current wedge (SCW). Each wedgelet is associated with a negative BX spike. Each spike is recorded at a higher latitude than the former one and all three are very localised over Fennoscandia. The first spike occurred at 17:34 UT and was observed at Lycksele, R rvik and Nurmij rvi, the second spike was recorded at 17:41 UT and located at Lycksele and R rvik, whereas the last spike occurred at 17:47 UT and was observed at Kevo and Abisko. Simultaneous optical auroral data and electron injections at the geosynchronous orbit indicate that one or more substorms took place in the polar ionosphere at the time of the wedgelets. This study demonstrates the occurrence of small and short-lived structures such as wedgelets at different locations over a short time scale, 15 min in this case.

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  • 12. Stergiopoulou, K.
    et al.
    Andrews, D. J.
    Edberg, N. J. T.
    Halekas, J.
    Kopf, A.
    Lester, M.
    Opgenoorth, Hermann J.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysik.
    Sanchez-Cano, B.
    Mars Express Observations of Cold Plasma Structures in the Martian Magnetotail2020Ingår i: Journal of Geophysical Research - Space Physics, ISSN 2169-9380, E-ISSN 2169-9402, Vol. 125, nr 10, artikel-id e2020JA028056Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We present observations from five Mars Express (MEX) orbits in September 2016 while the spacecraft passed through the Martian induced magnetotail at altitudes up to 3,500 km. On these orbits, the Mars Advanced Radar for Subsurface and Ionosphere Sounding (MARSIS) instrument was operated in Active Ionospheric Sounding (AIS) mode at much higher altitude than normal, acting as a local sounder and detecting cold plasma structures in this region. In this paper we combine MARSIS tail measurements with solar wind data from the Solar Wind Ion Analyzer (SWIA) instrument and the Magnetometer (MAG) from Mars Atmosphere and Volatile EvolutioN (MAVEN) in order to investigate possible factors affecting plasma transport from the dayside and through the terminator. MARSIS observed structured cold ionospheric plasma along its trajectory, at all altitudes and solar zenith angles (SZAs). Isolated regions of cold plasma were also observed on each orbit as the spacecraft crossed the terminator, even at high altitudes. We conclude that the variability of plasma seen in the tail results from a multifactorial transport process, the development of which cannot be attributed to a sole parameter influencing it, despite the availability of simultaneous high quality solar wind measurements.

  • 13.
    Sánchez-Cano, Beatriz
    et al.
    School of Physics and Astronomy, University of Leicester, Leicester, United Kingdom.
    Lester, Mark
    School of Physics and Astronomy, University of Leicester, Leicester, United Kingdom.
    Andrews, David J.
    Swedish Institute of Space Physics, Uppsala, Sweden.
    Opgenoorth, Hermann
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysik. School of Physics and Astronomy, University of Leicester, Leicester, United Kingdom.
    Lillis, Robert
    Space Sciences Laboratory, University of California Berkeley, CA, Berkeley, United States.
    Leblanc, François
    Laboratoire Atmosphères, Milieux, Observations Spatiales. Centre National de la Recherche Scientifique, Sorbonne Université, Paris, France.
    Fowler, Christopher M.
    Space Sciences Laboratory, University of California Berkeley, CA, Berkeley, United States.
    Fang, Xiaohua
    Laboratory for Atmospheric and Space Physics, University of Colorado Boulder, CO, Boulder, United States.
    Vaisberg, Oleg
    Space Research Institute of Russian academy of Sciences, Moscow, Russian Federation.
    Mayyasi, Majd
    Boston University, MA, Boston, United States.
    Holmberg, Mika
    European Space Research and Technology Center, European Space Agency, Noordwijk, Netherlands.
    Guo, Jingnan
    School of Earth and Space Sciences, University of Science and Technology of China, Hefei, China; CAS Center for Excellence in Comparative Planetology, Hefei, China.
    Hamrin, Maria
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysik.
    Mazelle, Christian
    Institut de Recherche en Astrophysique et Planétologie, Toulouse, France.
    Peter, Kerstin
    Department of Planetary Research, Rhenish Institute for Environmental Research at the University of Cologne, Cologne, Germany.
    Pätzold, Martin
    Department of Planetary Research, Rhenish Institute for Environmental Research at the University of Cologne, Cologne, Germany.
    Stergiopoulou, Katerina
    Swedish Institute of Space Physics, Uppsala, Sweden.
    Goetz, Charlotte
    European Space Research and Technology Center, European Space Agency, Noordwijk, Netherlands.
    Ermakov, Vladimir Nikolaevich
    Space Research Institute of Russian academy of Sciences, Moscow, Russian Federation.
    Shuvalov, Sergei
    Space Research Institute of Russian academy of Sciences, Moscow, Russian Federation.
    Wild, James A.
    Physics Department, Lancaster University, Lancaster, United Kingdom.
    Blelly, Pierre-Louis
    Institut de Recherche en Astrophysique et Planétologie, Toulouse, France.
    Mendillo, Michael
    Boston University, MA, Boston, United States.
    Bertucci, Cesar
    Instituto de Astronomía y Física del Espacio, Buenos Aires, Argentina.
    Cartacci, Marco
    Istituto Nazionale di Astrofisica, IAPS, Rome, Italy.
    Orosei, Roberto
    Istituto Nazionale di Astrofisica, Istituto di Radioastronomia, Bologna, Italy.
    Chu, Feng
    Department of Physics and Astronomy, University of Iowa, IA, Iowa City, United States.
    Kopf, Andrew J.
    Astronomical Applications Department, United States Naval Observatory, DC, Washington, United States.
    Girazian, Zachary
    Department of Physics and Astronomy, University of Iowa, IA, Iowa City, United States.
    Roman, Michael T.
    School of Physics and Astronomy, University of Leicester, Leicester, United Kingdom.
    Mars’ plasma system. Scientific potential of coordinated multipoint missions: "The next generation"2022Ingår i: Experimental astronomy, ISSN 0922-6435, E-ISSN 1572-9508, Vol. 54, s. 641-676Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The objective of this White Paper, submitted to ESA’s Voyage 2050 call, is to get a more holistic knowledge of the dynamics of the Martian plasma system, from its surface up to the undisturbed solar wind outside of the induced magnetosphere. This can only be achieved with coordinated multi-point observations with high temporal resolution as they have the scientific potential to track the whole dynamics of the system (from small to large scales), and they constitute the next generation of the exploration of Mars analogous to what happened at Earth a few decades ago. This White Paper discusses the key science questions that are still open at Mars and how they could be addressed with coordinated multipoint missions. The main science questions are: (i) How does solar wind driving impact the dynamics of the magnetosphere and ionosphere? (ii) What is the structure and nature of the tail of Mars’ magnetosphere at all scales? (iii) How does the lower atmosphere couple to the upper atmosphere? (iv) Why should we have a permanent in-situ Space Weather monitor at Mars? Each science question is devoted to a specific plasma region, and includes several specific scientific objectives to study in the coming decades. In addition, two mission concepts are also proposed based on coordinated multi-point science from a constellation of orbiting and ground-based platforms, which focus on understanding and solving the current science gaps.

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  • 14.
    Sánchez-Cano, Beatriz
    et al.
    School of Physics and Astronomy, University of Leicester, Leicester, United Kingdom.
    Witasse, Olivier
    European Space Agency, European Space Research and Technology Centre (ESTEC), Noordwijk, Netherlands.
    Knutsen, Elise W.
    LATMOS/IPSL, UVSQ Université Paris-Saclay, Sorbonne Université, CNRS, Guyancourt, France.
    Meggi, Dikshita
    School of Physics and Astronomy, University of Leicester, Leicester, United Kingdom.
    Viet, Shayla
    LATMOS/IPSL, UVSQ Université Paris-Saclay, Sorbonne Université, CNRS, Guyancourt, France.
    Lester, Mark
    School of Physics and Astronomy, University of Leicester, Leicester, United Kingdom.
    Wimmer-Schweingruber, Robert F.
    Institute of Experimental and Applied Physics, Christian-Albrechts-University, Kiel, Germany.
    Pinto, Marco
    European Space Agency, European Space Research and Technology Centre (ESTEC), Noordwijk, Netherlands.
    Moissl, Richard
    European Space Agency, European Space Research Institute (ESRIN), Frascati, Italy.
    Benkhoff, Johannes
    European Space Agency, European Space Research and Technology Centre (ESTEC), Noordwijk, Netherlands.
    Opgenoorth, Hermann J.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysik. School of Physics and Astronomy, University of Leicester, Leicester, United Kingdom.
    Auster, Uli
    Institut für Geophysik und extraterrestrische Physik, Technische Universität Braunschweig, Braunschweig, Germany.
    de Brujine, Jos
    European Space Agency, European Space Research and Technology Centre (ESTEC), Noordwijk, Netherlands.
    Collins, Peter
    European Space Agency, European Space Operations Centre (ESOC), Darmstadt, Germany.
    De Marchi, Guido
    European Space Agency, European Space Research and Technology Centre (ESTEC), Noordwijk, Netherlands.
    Fischer, David
    Space Research Institute, Austrian Academy of Sciences, Graz, Austria.
    Futaana, Yoshifumi
    Swedish Institute of Space Physics, Kiruna, Sweden.
    Godfrey, James
    European Space Agency, European Space Operations Centre (ESOC), Darmstadt, Germany.
    Heyner, Daniel
    Institut für Geophysik und extraterrestrische Physik, Technische Universität Braunschweig, Braunschweig, Germany.
    Holmstrom, Mats
    Swedish Institute of Space Physics, Kiruna, Sweden.
    Johnstone, Andrew
    European Space Agency, European Space Operations Centre (ESOC), Darmstadt, Germany.
    Joyce, Simon
    School of Physics and Astronomy, University of Leicester, Leicester, United Kingdom.
    Lakey, Daniel
    European Space Agency, European Space Operations Centre (ESOC), Darmstadt, Germany.
    Martinez, Santa
    European Space Agency, European Space Astronomy Centre (ESAC), Villafranca del Castillo, Spain.
    Milligan, David
    European Space Agency, European Space Operations Centre (ESOC), Darmstadt, Germany.
    Montagnon, Elsa
    European Space Agency, European Space Astronomy Centre (ESAC), Villafranca del Castillo, Spain.
    Müller, Daniel
    European Space Agency, European Space Research and Technology Centre (ESTEC), Noordwijk, Netherlands.
    Livi, Stefano A.
    Southwest Research Institute, TX, San Antonio, United States; Department of Climate and Space Sciences and Engineering, University of Michigan, MI, Ann Arbor, United States.
    Prusti, Timo
    European Space Agency, European Space Research and Technology Centre (ESTEC), Noordwijk, Netherlands.
    Raines, Jim
    Department of Climate and Space Sciences and Engineering, University of Michigan, MI, Ann Arbor, United States.
    Richter, Ingo
    Institut für Geophysik und extraterrestrische Physik, Technische Universität Braunschweig, Braunschweig, Germany.
    Schmid, Daniel
    Space Research Institute, Austrian Academy of Sciences, Graz, Austria.
    Schmitz, Peter
    European Space Agency, European Space Operations Centre (ESOC), Darmstadt, Germany.
    Svedhem, Håkan
    Delft University, Delft, Netherlands.
    Taylor, Matt G. G. T.
    European Space Agency, European Space Research and Technology Centre (ESTEC), Noordwijk, Netherlands.
    Tremolizzo, Elena
    European Space Agency, European Space Research and Technology Centre (ESTEC), Noordwijk, Netherlands.
    Titov, Dimitri
    Leiden Observatory, Leiden, Netherlands.
    Wilson, Colin
    European Space Agency, European Space Research and Technology Centre (ESTEC), Noordwijk, Netherlands.
    Wood, Simon
    European Space Agency, European Space Operations Centre (ESOC), Darmstadt, Germany.
    Zender, Joe
    European Space Agency, European Space Research and Technology Centre (ESTEC), Noordwijk, Netherlands.
    Solar Energetic Particle Events Detected in the Housekeeping Data of the European Space Agency's Spacecraft Flotilla in the Solar System2023Ingår i: Space Weather: The International Journal of Research and Application, E-ISSN 1542-7390, Vol. 21, nr 8, artikel-id e2023SW003540Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Despite the growing importance of planetary Space Weather forecasting and radiation protection for science and robotic exploration and the need for accurate Space Weather monitoring and predictions, only a limited number of spacecraft have dedicated instrumentation for this purpose. However, every spacecraft (planetary or astronomical) has hundreds of housekeeping sensors distributed across the spacecraft, some of which can be useful to detect radiation hazards produced by solar particle events. In particular, energetic particles that impact detectors and subsystems on a spacecraft can be identified by certain housekeeping sensors, such as the Error Detection and Correction (EDAC) memory counters, and their effects can be assessed. These counters typically have a sudden large increase in a short time in their error counts that generally match the arrival of energetic particles to the spacecraft. We investigate these engineering datasets for scientific purposes and perform a feasibility study of solar energetic particle event detections using EDAC counters from seven European Space Agency Solar System missions: Venus Express, Mars Express, ExoMars-Trace Gas Orbiter, Rosetta, BepiColombo, Solar Orbiter, and Gaia. Six cases studies, in which the same event was observed by different missions at different locations in the inner Solar System are analyzed. The results of this study show how engineering sensors, for example, EDAC counters, can be used to infer information about the solar particle environment at each spacecraft location. Therefore, we demonstrate the potential of the various EDAC to provide a network of solar particle detections at locations where no scientific observations of this kind are available.

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