Local News
Showing 1 to 24 of 32.
New Paper! Ionospheric Response to the 10 May 2024 Geomagnetic Storm as Observed in GNSS Radio Occultation Electron Density
2025.03.12
Wonseok (Andrew) Lee (CUA/675) Guiping Liu (675), Dong Wu (613), Douglas Rowland (675), 2025: "Ionospheric Response to the 10 May 2024 Geomagnetic Storm as Observed in GNSS Radio Occultation Electron Density", Journal of Geophysical Research, https://doi.org/10.1029/2024JA033489, This paper studies the spatiotemporal and altitude variations in ionospheric F-region electron density in response to the 10 May 2024 geomagnetic storm. Using the unprecedented sampling by ~12,000 electron density profile each day from radio occultation observations, the study found that F-region TEC decreased globally while topside TEC increased, with peak heights rising during daytime and falling at night in low latitudes. Additionally, the equatorial ionospheric anomaly expanded significantly immediately after the storm onset and then remained merged for approximately one day.
New Paper! Impact of Arctic and Antarctic sudden stratospheric warmings on thermospheric composition
2025.01.31
Zhang, J. (Utah State U.), O. Jens (Clemson Univ.), N.M. Pedatella (UCAR), G. Liu (675), 2005 "Impact of Arctic and Antarctic sudden stratospheric warmings on thermospheric composition", Journal of Geophysical Research, https://doi.org/10.1029/2024JA032562. This paper studies the impact of SSWs on thermospheric composition changes during both Arctic and Antarctic SSW events from 2018-2021, using GOLD and GUVI observations and WACCM-X simulations. The results show that O/N2 is reduced by ~10% at low-to-mid latitudes following the Arctic SSW onset while the changes are less pronounced during the 2019 Antarctic SSW. These O/N2 changes are likely associated with the reversals of the lower thermosphere mean meridional circulation arising from westward propagating planetary waves.
Chapter published! "Traveling Ionospheric Disturbances" was published in the "Reference Module in Earth Systems and Environmental Sciences,"
2025.01.22
The chapter "Traveling Ionospheric Disturbances" was published in the "Reference Module in Earth Systems and Environmental Sciences," published by Elsevier. This chapter provides an overview of these plasma irregularities, including history of observations, generation mechanisms, and outstanding questions. Angeline G. Burrell (NRL), Jeff Klenzing (675), Kate A. Zawdie (NRL), Traveling Ionospheric Disturbances, Reference Module in Earth Systems and Environmental Sciences, Elsevier, 2024, ISBN 9780124095489, https://doi.org/10.1016/B978-0-323-96026-7.00173-9.
New paper: "Resolving the Generation Mechanisms and Electrodynamical Effects of Medium Scale Traveling Ionospheric Disturbances (MSTIDs)"
2025.01.22
The paper "Resolving the Generation Mechanisms and Electrodynamical Effects of Medium Scale Traveling Ionospheric Disturbances (MSTIDs)" was accepted in Frontiers in Astronomy and Space Sciences. This paper presents an overview of propagating structures in ionospheric plasma density, includes multiple generation mechanisms such as ion-neutral collisions, plasma instabilities, and electromagnetic forcing. Observational limitations can impede characterization and identification of MSTID generation mechanisms. We discuss inconsistencies in current terminology used to describe these and provide a set of recommendations for description and discussion. Jeff Klenzing (675), Kate Zawdie (Naval Research Laboratory (NRL)), Elvira Astafyeva (Institut de Physique du Globe de Paris), Anna Belehaki (National Observatory of Athens), Meghan Burleigh (NRL), Angeline G. Burrell (NRL), Cosme A. Figueiredo (Federal University of Campina Grande), Nathaniel A. Frissell (University of Scranton), Weizheng Fu (Nagoya University), Dustin Hickey (NRL), Joe Huba (Symtek Technologies / 675), Pavel Inchin (Computational Physics), Stephen R. Kaeppler (Clemson University), V Lakshmi Narayanan (Krea University), Mani Sivakandan (Leibniz Institute of Atmospheric Physics), Jonathon Smith (CUA/675), Chao Xiong (Wuhan University), Tatsuhiro Yokoyama (Kyoto University), Matt Zettergren (Embry-Riddle Aeronautical University), Shun-Rong Zhang (MIT Haystack Observatory), Resolving the Generation Mechanisms and Electrodynamical Effects of Medium Scale Traveling Ionospheric Disturbances (MSTIDs), Front. Astron. Space Sci., Volume 12, 2025, doi: 10.3389/fspas.2025.1539821
New Paper out: Understanding and modeling the dynamics of storm-time atmospheric neutral density using random forests
2025.01.06
We have a new paper out with our colleagues! Murphy, K. (Northumbria University) , Halford, A. J. (675), Liu, V. (John Hopkins University), Klenzing, J. (675), Smith, J. (CUA/675), Garcia-Sage, K. (674), Pettit, J. (George Mason 674), Rae, J. (Northumbria University) (2025). Understanding and modeling the dynamics of storm-time atmospheric neutral density using random forests. Space Weather, 23, e2024SW003928. https://doi.org/10.1029/2024SW003928. Even though low Earth-orbiting satellites are in space where the density of air is thin, they still experience drag or friction as they fly through what little atmosphere there is along their orbit. This drag causes satellite orbits to decay over time. During enhanced space weather, such as geomagnetic storms, this drag increases, making it difficult to track and predict the motion of satellites. In this work, we develop a new model that includes solar and geomagnetic proxies for predicting atmospheric density, the key contributor to satellite drag, utilizing combined solar and geomagnetic data. This new model performs better than models based only on solar data, especially during geomagnetic storms and periods of extreme space weather. Overall, this work highlights the importance of near-Earth processes in enhancing satellite drag during geomagnetic storms.
New paper out! The Impact of Lower Atmosphere Forecast Uncertainties on WACCM-X Prediction of Ionosphere-Thermosphere System During Geomagnetic Storms.
2025.01.06
Wonseok (Andrew) Lee (CUA/675), In-Sun Song (Yonsei University), Ja Soon Shim (USRA/674), Guiping Liu (675), and Geonhwa Jee (KOPRI) (2024). The Impact of Lower Atmosphere Forecast Uncertainties on WACCM-X Prediction of Ionosphere-Thermosphere System During Geomagnetic Storms. Space Weather, 22, e2024SW004137, https://doi.org/10.1029/2024SW004137 , This paper investigates the impact of lower atmosphere forecast uncertainties on the Ionosphere-Thermosphere system using the WACCM-X for April 2010 and March 2013 geomagnetic storms. The forecast errors in TEC could be due to the deviations in the tidal waves.
The ITM Lab Bookends the NASA Calendar!
2025.01.01
Aurorasaurus and Spritacular citizen scientists are featured in the 2025 NASA Science Calendar (https://science.nasa.gov/multimedia/2025-nasa-science-planning-guide/). The month of January features a photo by Aurorasaurus Ambassador Gunjan Sinha, and December features a photo by Spritacular participant Nicolas Escurat. You can download the images and the calendar at https://science.nasa.gov/multimedia/2025-nasa-science-planning-guide/
New Paper: Association of structured continuum emission with dynamic aurora
2024.12.30
New Nature paper out with our collaborators titled "Association of structured continuum emission with dynamic aurora" Spanswick, E., Liang, J., Houghton, J. et al. Association of structured continuum emission with dynamic aurora. Nat Commun 15, 10802 (2024). https://doi.org/10.1038/s41467-024-55081-5 https://www.nature.com/articles/s41467-024-55081-5
New Paper Alert
2024.12.16
New paper out in Geophysical Research articles with our collaborators: Elliott, S. S., Colpitts, C., Breneman, A. W., Pettit, J. M., Cantwell, K. A., Cattell, C. A., et al. (2024). A multi-platform statistical analysis of the azimuthal spatial extent of the microburst precipitation region. Journal of Geophysical Research: Space Physics, 129, e2024JA033208. https://doi.org/10.1029/2024JA033208 Microbursts are short-duration (<1 s) bursts of electrons that precipitate from the magnetosphere into the atmosphere. They are thought to be caused by scattering by a plasma wave called chorus. Microburst precipitation contributes to outer radiation belt loss after enhancements during geomagnetic storms. The contribution depends on the size and duration of the microburst region. We present a statistical analysis of chorus and energetic electron precipitation to determine the size of the microburst precipitation region. We also analyze how the size depends on geomagnetic activity. Our results show that the region is often large and the size increases with geomagnetic activity.
New paper on the aurora with Citizen Scientists out!
2024.12.04
New paper with our collaborators, Grandin, M. (FMI), Bruus, E. (Citizen Scientist), Ledvina, V. E. (UAF), Partamies, N. (UNIS), Barthelemy, M. (Université Grenoble Alpes), Martinis, C. (BU), Dayton-Oxland, R. (University of Southampton), Gallardo-Lacourt, B. (CUA/675), Nishimura, Y. (BU), Herlingshaw, K. (UNIS), Thomas, N. (University of Oulu), Karvinen, E. (Citizen Scientist), Lach, D. (Citizen Scientist), Spijkers, M. (Citizen Scientist), and Bergstrand, C. (Citizen Scientist): The geomagnetic superstorm of 10 May 2024: Citizen science observations, EGUsphere, https://doi.org/10.5194/egusphere-2024-2174, 2024. In this recently accepted paper, we analyzed citizen scientist data to study the Gannon Storm of 10 May 2024. We gathered 696 reports from over 30 countries, including details on aurora sightings, colors, forms, and disruptions like network and power failures. Additionally, we incorporated 186 auroral observations from the Skywarden catalog. Our findings revealed that the aurora was visible at geomagnetic latitudes between 30° and 60°, well beyond predictions, with some reports from lower latitudes. The observed aurora had predominantly red and pink colors, likely due to large fluxes of low-energy particles (<1 keV). The study highlights the value of citizen science but also the challenges of using basic online forms for data collection, suggesting ways to improve future studies on extreme geomagnetic events.
New paper out led by our collaborators on Medium-scale traveling ionospheric disturbances created by primary gravity waves generated by a winter storm.
2024.12.02
New paper out by Masaru Kogure (674/CUA), Ming-Yang Chou (674/CUA), Jia Yue (674/CUA), Yuichi Otsuka (Nagoya Univ. - Japan) , Huxin Liu (Kyushu Univ. Japan), Fabrizio Sassi (675), Nicholas Pedatella (HAO, Boulder), Cora E. Randall ((Univ. of Colorado, Boulder), and Lynn Harvey (Univ. of Colorado) have their paper accepted in Journal of Space Weather and Space Climate on Medium-scale traveling ionospheric disturbances created by primary gravity waves generated by a winter storm. This study explores the meteorological source and vertical propagation of gravity waves that drive daytime traveling ionospheric disturbances, using the specified dynamics version of the Whole Atmosphere Community Climate Model with thermosphere-ionosphere eXtension (SD-WACCM-X) and the Sami3 is Also a Model of the Ionosphere (SAMI3) simulations driven by SD-WACCM-X neutral wind and composition.
New Paper! The geomagnetic superstorm of 10 May 2024: Citizen science observations
2024.11.18
In this recently accepted paper, we analyzed citizen scientist data to study the Gannon Storm of 10 May 2024. We gathered 696 reports from over 30 countries, including details on aurora sightings, colors, forms, and disruptions like network and power failures. Additionally, we incorporated 186 auroral observations from the Skywarden catalog. Our findings revealed that the aurora was visible at geomagnetic latitudes between 30° and 60°, well beyond predictions, with some reports from lower latitudes. The observed aurora had predominantly red and pink colors, likely due to large fluxes of low-energy particles (<1 keV). The study highlights the value of citizen science but also the challenges of using basic online forms for data collection, suggesting ways to improve future studies on extreme geomagnetic events. Grandin, M. (FMI), Bruus, E. (Citizen Scientist), Ledvina, V. E. (UAF), Partamies, N. (UNIS), Barthelemy, M. (Université Grenoble Alpes), Martinis, C. (BU), Dayton-Oxland, R. (University of Southampton), Gallardo-Lacourt, B. (CUA/675), Nishimura, Y. (BU), Herlingshaw, K. (UNIS), Thomas, N. (University of Oulu), Karvinen, E. (Citizen Scientist), Lach, D. (Citizen Scientist), Spijkers, M. (Citizen Scientist), and Bergstrand, C. (Citizen Scientist): The geomagnetic superstorm of 10 May 2024: Citizen science observations, EGUsphere, https://doi.org/10.5194/egusphere-2024-2174, 2024.
New Paper! Auroral and magnetotail dynamics during quiet-time STEVE and SAID
2024.11.14
This paper explores quiet-time STEVE events, demonstrating that they share similar characteristics with substorm-time STEVE despite occurring during non-substorm auroral intensifications. During these quiet-time events, THEMIS satellites detected dipolarization fronts and fast plasma flows in the magnetotail, indicating that transient energy release in the plasma sheet was the source of both quiet-time STEVE and SAID). Unlike substorm-associated events, these quiet-time STEVE occurrences featured weaker particle injections and lower electron temperatures. Additionally, the plasmapause extended beyond geosynchronous orbit, with weak ring and tail currents observed. These findings suggest that even small energy releases in a quiet magnetosphere can significantly influence flow patterns and field-aligned current systems. Nishimura, Y. (BU), Gallardo-Lacourt, B. (675/CUA), Donovan, E. F. (University of Calgary), Angelopoulos, V. (UCLA), & Nishitani, N. (Nagoya University), 2024. Auroral and magnetotail dynamics during quiet-time STEVE and SAID. JGR: Space Physics, 129, e2024JA032941. https://doi.org/10.1029/2024JA032941.
New Paper: Increasing Mars Global Surveyor and Mars Atmosphere and Volatile EvolutioN Dataset Utility. Data
2024.11.14
Within this paper we discuss the process used to create an amended dataset and store it on the SPDF. The operational software to generate the archival data software uses the open-source Python package pysat, and an end-user module has been added to the pysatNASA module. The result is the addition of data products to the Mars Global Surveyor (MGS) magnetometer (MAG) dataset, its archival location on SPDF, and pysat compatibility. The primary and metadata format increases the convenience and efficiency for users of the MGS MAG data, and storage on SPDF increases the data's findability for the heliophysics community. The storage of planetary and heliophysics data in one location supports the use of data throughout the solar system for comparative studies, while the pysat compatibility enables loading data in an identical format for ease of processing. We encourage the use of the outlined process for past, present, and future space science missions of all sizes and funding levels. This includes balloons to Flagship-class missions. Esman TM (NPP/675), Halford AJ (675), Klenzing J (675), Burrell AG(NRL). Additions to Space Physics Data Facility and pysatNASA: Increasing Mars Global Surveyor and Mars Atmosphere and Volatile EvolutioN Dataset Utility. Data. 2024; 9(11):133. https://doi.org/10.3390/data9110133
New Paper Variation of the altitude of auroral emission during a substorm cycle: Stereoscopic optical observations during the LAMP rocket experiment
2024.11.12
This paper is from the LAMP (Loss from auroral microbursts precipitation) Rocket mission. We used multiple ground based observatories to determine the altitude of the aurora which allows us to infer the energy of the electrons contributing to the auroral light display. Movies of how this changes can be found in the supplemental information at the end of the paper. Hosokawa, K. (University of Electro-Communications, Tokyo, Japan), Miyoshi, Y. (Nagoya University, Nagoya, Japan), Mcharg, M. (USAF Academy), Ledvina, V. (University of Alaska Fairbanks), Hampton, D. (University of Alaska Fairbanks), Lessard, M. (UNH), M. Shumko (APL/JHU), K. Asamura (JAXA), T. Sakanoi (Tohoku University, Sendai, Japan), T. Mitani (JAXA), T. Namekawa(JAXA), M. Nosé(Nagoya City University, Nagoya, Japan), Y. Ogawa(National Institute of Polar Research, Tokyo, Japan), A. Jaynes(U.Iowa), A. Halford (675) (2024). Variation of the altitude of auroral emission during a substorm cycle: Stereoscopic optical observations during the LAMP rocket experiment. Journal of Geophysical Research: Space Physics, 129, e2024JA033036. https://doi.org/10.1029/2024JA033036
New Paper! Quantifying the mesoscale contribution to FACs during a magnetospheric substorm
2024.10.30
In this paper, we use a new ionospheric data assimilation technique, Lompe (Local mapping of the polar ionospheric electrodynamics), to specify ionospheric electrodynamics using a wide variety of input data and a priori assumptions about the physical nature of the ionospheric electric field. We isolate the terms of the ionospheric Ohm's law and find that mesoscale structures in the FACs are driven by Hall gradients, while the larger scale patterns are associated with the divergence of the electric field. We calculate the relative contribution of mesoscales to the overall FAC patterns during a magnetospheric substorm, and find that in the nightside, mesoscale FACs contribute up to 60% of the total. Gasparini, S., L. Kepko (675), and K. Laundal, 2024: "Quantifying the mesoscale contribution to FACs during a magnetospheric substorm", Geophys. Res. Lett. https://doi.org/10.1029/2024GL111045
New Paper: Unexpected STEVE observations at high latitude during quiet geomagnetic conditions
2024.10.08
In this paper, we analyzed an unusual observation of STEVE at very high latitudes, which occurred under exceptionally quiet geomagnetic conditions. This event was captured by one of the University of Calgary’s RGB all-sky imagers from the Transition Region Explorer (TREx) array, as well as by an AurorEye imaging system developed and operated by citizen scientists. Despite the quiet geomagnetic conditions, the observation revealed intense ionospheric electrodynamics, including a Subauroral Ion Drift (SAID) exceeding 4 km/s. This unique case study raises new questions about subauroral dynamics and the impact of magnetospheric configurations on the ionospheric response. Bea Gallardo-Lacourt (675/CUA), Toshi Nishimura (BU), Larry Kepko (675), Emma Spanswick (University of Calgary), D. Megan Gillies (Mount Royal University), David Knudsen (University of Calgary), Jonathan Burchill (University of Calgary), Susan Skone (University of Calgary), Victor Pinto (University of Santiago), Darren Chaddock (University of Calgary), Jeremy Kuzub (Citizen Scientists/ AurorEye), and Eric Donovan (University of Calgary) 2024: Unexpected STEVE observations at high latitude during quiet geomagnetic conditions. Geophysical Research Letters, https://doi.org/10.1029/2024GL110568.
New paper published: Special issue “16th International Symposium on Equatorial Aeronomy (ISEA-16), 2022”
2024.09.13
This special issue discusses the findings of the 16th International Symposium on Equatorial Aeronomy, which was held at the Research Institute for Sustainable Humanosphere, Kyoto University, Japan in September 2022. The meeting brought together researchers from atmospheric, ionospheric and magnetospheric sciences to discuss the current status and key questions of low-latitude aeronomy. The preface here summarizes the contributed papers. Yokoyama, T. (Kyoto University), Klenzing, J. (675), Milla, M.A. (Pontificia Universidad Catolica del Peru), Stolle, C. (Leibniz Institute of Atmospheric Physics, Germany), and Pallamraju, D. (Physical Research Laboratory, India). Special issue “16th International Symposium on Equatorial Aeronomy (ISEA-16), 2022”. Earth Planets Space 76, 115 (2024). https://doi.org/10.1186/s40623-024-02052-1.
New Paper out! Identifying the magnetospheric drivers of giant undulations
2024.09.13
This paper presents the first global simulation of giant undulations (GU) using the MAGE model to identify their magnetospheric drivers. The model successfully reproduces both the spatial and temporal scales of GU, while pinpointing mesoscale ring current injections, which drift westward, as the magnetospheric drivers behind these phenomena. Sorathia, K. A. (JHU/APL), Shumko, M. (JHU/APL), Sciola, A. (JHU/APL), Michael, A. (JHU/APL), Merkin, V. G. (JHU/APL), Gallardo-Lacourt, B. (675/CUA), Henderson, M. G. (LANL), Lin D. (NCAR/HAO), Bao, S. (Rice University), Garretson J. (JHU/APL), and Ukhorskiy (JHU/APL), 2024: “Identifying the magnetospheric drivers of giant undulations: Global modeling of the evolving inner magnetosphere and its auroral manifestations,” GRL, 51, e2024GL110772. https://doi.org/10.1029/2024GL110772.
New Paper Out! Exploring the relationship between STEVE and SAID during three events observed by SuperDARN
2024.08.26
Macho EP, Bristow W, Gallardo-Lacourt B, Shepherd SG, Ruohoniemi JM and Correia E (2024) Exploring the relationship between STEVE and SAID during three events observed by SuperDARN. Front. Astron. Space Sci. 11:1422164. doi: 10.3389/fspas.2024.1422164 Abstract: The phenomenon known as strong thermal emission velocity enhancement (STEVE) is a narrow optical structure that may extend longitudinally for thousands of kilometers. Initially observed by amateur photographers, it has recently garnered researchers’ attention. STEVE has been associated with a rapid westward flow of ions in the ionosphere, known as subauroral ion drift (SAID). In this work, we investigate three occurrences of STEVE, using data from one of the Time History of Events and Macroscale Interactions during Substorms (THEMIS) ground-based all-sky imagers (ASIs) located at Pinawa, Manitoba, and from the Super Dual Auroral Radar Network (SuperDARN). This approach allows us to verify the correlation between STEVE and SAID, as well as analyze the temporal variation of SAID observed during STEVE events. Our results suggest that the SAID activity starts before the STEVE, and the magnitude of the westward flow decreases as the STEVE progresses toward the end of its optical manifestation. Read the full paper at https://www.frontiersin.org/journals/astronomy-and-space-sciences/articles/10.3389/fspas.2024.1422164/full
New Paper! Solar Wind Drivers of Auroral Omega Bands
2024.08.26
Cribb, V., Pulkkinen, T. I., Kepko, L., Gallardo-Lacourt, B., & Donovan, E. (2024). Solar wind drivers of auroral omega bands. Geophysical Research Letters, 51, e2024GL109756. https://doi.org/10.1029/2024GL109756 Omega bands are eastward moving wave-like structures in the aurora that typically appear at the equatorward border of the auroral oval during periods of enhanced activity in Earth's magnetosphere. However, the specific drivers of these structures are not well understood. In this work, we perform a statistical analysis of spacecraft observations taken from multiple omega band events to identify potential drivers of these structures. We find that the solar wind exhibits increased speed, pressure, and particle density when omega bands appear overhead. These features are consistent with localized compression in the solar wind generated when a fast solar wind stream interacts with a slower leading stream. Our work suggests that the appearance of omega bands is driven by this compression. Read the full paper at https://doi.org/10.1029/2024GL109756
New Paper Published: A Survey of EMIC Waves in Van Allen Probe Data
2024.08.26
Inglis, A. R., Murphy, K. R., & Halford, A. (2024). A Survey of EMIC waves in Van Allen Probe data. Journal of Geophysical Research: Space Physics, 129, e2024JA032666. https://doi.org/10.1029/2024JA032666 Summary: Electromagnetic Ion Cyclotron (EMIC) waves are found throughout Earth's magnetosphere and the solar system. These waves in Earth's magnetosphere interact with the ring current and radiation belt population and push these particles into our atmosphere. Thus, it is useful to know when and where these waves occur. In this paper, we present a new approach toward identifying these waves in large data sets. Using this new approach, we identified 500 hr of EMIC waves from the Van Allen Probe B data set between Jan 2013–July 2019. Our catalog of events follows similar statistics found for EMIC waves by others, validating our methodology. Like others, we found that the waves occur more frequently on the dayside of the Earth. Higher amplitude waves were found at greater distances from the Earth, close to the edge of the magnetosphere. It was also found that the wave activity was greater during periods of geomagnetic activity than during quiet conditions. And in the interest of open science, we have made both the detection code and the list of waves available to the public. The full paper can be found at https://doi.org/10.1029/2024JA032666
New paper published in Physical Review Letters!
2024.07.22
"New Regime of Inertial Alfvén Wave Turbulence in the Auroral Ionosphere" was published in Physical Review Letters on July 22nd, 2024, by Francesca Di Mare (Catholic University of America and NASA Goddard ITM lab ) and Gregory G. Howes (Department of Physics and Astronomy, University of Iowa). The DOI:https://doi.org/10.1103/PhysRevLett.133.045201
New Paper! A Quantitative Analysis of the Uncertainties on Reconnection Electric Field Estimates Using Ionospheric Measurements
2024.06.21
New paper published by our own Sara Gasparini (Department of Physics and Technology, University of Bergen, Bergen, Norway and the NASA/GSFC ITM Lab) et al in the Journal of Geophysical Research: Space physics. Gasparini, S., Hatch, S. M., Reistad, J. P., Ohma, A., Laundal, K. M., Walker, S. J., & Madelaire, M. (2024). A quantitative analysis of the uncertainties on reconnection electric field estimates using ionospheric measurements. Journal of Geophysical Research: Space Physics, 129, e2024JA032599. https://doi.org/10.1029/2024JA032599
Showing 1 to 24 of 32.