A5102901170- Ionosphere and magnetosphere dynamics
- Solar and Space Plasma Dynamics
- Geomagnetism and Paleomagnetism Studies
- Earthquake Detection and Analysis
- GNSS positioning and interference
- Geophysics and Gravity Measurements
- Hemoglobin structure and function
- Spectroscopy and Quantum Chemical Studies
- Atmospheric Ozone and Climate
- Astro and Planetary Science
- Nitric Oxide and Endothelin Effects
- Electron Spin Resonance Studies
- Photoreceptor and optogenetics research
- Oceanographic and Atmospheric Processes
- Teleoperation and Haptic Systems
- Robot Manipulation and Learning
- Heme Oxygenase-1 and Carbon Monoxide
- Photosynthetic Processes and Mechanisms
- Mass Spectrometry Techniques and Applications
- Space Science and Extraterrestrial Life
- Seismic Waves and Analysis
- Erythrocyte Function and Pathophysiology
- Underwater Vehicles and Communication Systems
- Protein Structure and Dynamics
- Plasma Diagnostics and Applications
Korea Astronomy and Space Science Institute
2015-2024
Korea University of Science and Technology
2016-2024
Seoul National University
2011-2024
Korea University
2019-2024
Western University
2023
University of Saskatchewan
2023
Pusan National University
2007-2018
GFZ Helmholtz Centre for Geosciences
2008-2015
Busan National University of Education
2014
University of Potsdam
2010-2013
Swarm, a three-satellite constellation to study the dynamics of Earth’s magnetic field and its interactions with Earth system, is expected be launched in late 2013. The objective Swarm mission provide best ever survey geomagnetic temporal evolution, order gain new insights into system by improving our understanding interior environment. In derive advanced models (and other higher-level data products) it necessary take explicit advantage aspect Swarm. SCARF (SatelliteConstellationApplication...
We present a statistical study of the temporal- and spatial-scale characteristics different field-aligned current (FAC) types derived with Swarm satellite formation. divide FACs into two classes: small-scale, up to some 10 km, which are carried predominantly by kinetic Alfvén waves, large-scale sizes more than 150 km. For determining temporal variability we consider measurements at same point, orbital crossovers near poles, but times. From correlation analysis obtain persistent period...
Abstract. Based on the multi-year data base (2001–2009) of CHAMP Planar Langmuir Probe (PLP) and GRACE K-Band Ranging (KBR1B) data, typical features ionospheric plasma irregularities are studied at altitudes (300–400 km) (~500 km). The phenomena we focusing equatorial bubbles (EPBs). Similar seasonal/longitudinal (S/L) distributions EPB have been found both during solar active quiet years. Peak occurrence rates, defined as number events within an S/L bin divided by passes over that bin,...
In this study, we investigated the scale sizes of equatorial plasma irregularities (EPIs) using measurements from Swarm satellites during its early mission and final constellation phases. We found that with longitudinal separation between larger than 0.4°, no significant correlation was any more. This result suggests EPI structures include density less 44 km in zonal direction. During earlier phase, clearly better correlations are obtained northern hemisphere, implying more fragmented...
Using the equatorial electrojet (EEJ) peak current intensity as deduced from CHAMP magnetic observations years 2001 through 2009, we investigated relationship between sudden stratospheric warming (SSW) and lunitidal signatures in tropical ionosphere. There is a practically one‐to‐one correspondence midwinter SSW periods strongest 13 day modulation of EEJ strength observed by CHAMP. That is, all December to August 2009 were accompanied an enhanced strength. No other geophysical phenomenon...
Abstract Based on magnetic field data sampled by the Swarm satellite constellation it is possible for first time to determine uniquely F region currents at low latitudes. Initial results are presented from 200 days of formation flight (17 April 5 November 2014). Detailed have been obtained interhemispheric field‐aligned connecting solar quiet day variation ( Sq ) current systems in two hemispheres. We obtain prominent Southern (winter) Hemisphere Northern around noon. Weaker opposite...
Abstract We present multimission observations of field‐aligned currents, auroral oval, and magnetopause crossings during the 17 March 2015 magnetic storm. Dayside reconnection is expected to transport flux, strengthen lead polar cap expansion erosion. Our assemble evidence for all these manifestations. After a prolonged period strongly southward interplanetary field, Swarm AMPERE observe significant intensification currents. The dayside as seen by DMSP, appears thin arc associated with...
This study reports comprehensive observations for the G5-level geomagnetic storm that occurred from May 10 to 12, 2024, most intense event since 2003 Halloween storm. The was triggered by a series of coronal mass ejections (CMEs) originating merging two active regions 13664/13668, which formed large and complex photospheric magnetic configuration produced X-class flares in early 2024. Among events, significant CME, driven an X2.2 flare on 9, caught up with merged preceding slower CME...
Abstract We investigate the climatology of Martian ionospheric disturbances using Mars Atmosphere and Volatile Evolution missioN (MAVEN) data in 2014–2023. The disturbance strength is estimated by calculating residuals situ density from its large‐scale (filter window size ∼560 km) background normalizing residual with background, as has been commonly used terrestrial aeronomy. are statistically stronger (a) local winter hemisphere than summer (b) on nightside dayside, stark contrast across...
We present multi-scale observations of a foreshock transient and its impact on the magnetosheath, magnetosphere ionosphere, utilizing data from Cluster, THEMIS, ground-based radars, magnetometers. During storm recovery phase March 25, 2015, Cluster spacecraft observed at GSE (8, -0.5, -13) Re. Subsequently, THEMIS A E, residing in equatorial plane, detected large-scale high-speed jets postnoon sector between 7 9 Re Earth. At geosynchronous orbit, GOES-13 crossed magnetopause, during which...
KASI has been developing LEO satellite observation missions to study the Earth's ionosphere and upper atmosphere. These include SNIPE (Small scale magNetospheric Ionospheric Plasma Experiment), SNIPE-2 Experiment-2), ROKITS (Republic Of Korea Imaging Test System), ATHENA (Aurora THErmosphere ioNosphere for spAceweather). The successful launch of Experiment) mission in May 2023, featuring a formation flight three nanosatellites, enables simultaneous spatio-temporal changes plasma...
In the post-sunset tropical ionospheric F-region plasma density often exhibits depletions, which are usually called equatorial bubbles (EPBs). this paper we give an overview of Swarm Level 2 Ionospheric Bubble Index (IBI), is a standard scientific data mission. This product L2-IBI generated from magnetic field and observations onboard Swarm, gives information as to whether observation affected by EPBs. We validate performance using measurements CHAMP satellite, provided similar those Swarm....
We investigated the magnetic signatures of plasma blobs, as observed by CHAMP satellite. In total, we have identified 52 blobs with clear density enhancements and signatures. each blob field strength was depressed, components perpendicular to main direction showed fluctuations. The variation in implies that enhanced pressure is balanced a reduction, deflection indicates presence field‐aligned currents. Both characteristics are consistent bubble Concurrent observations (at ∼350 km altitude)...
Abstract. By using 3-year global positioning system (GPS) measurements from December 2013 to November 2016, we provide in this study a detailed survey on the climatology of GPS signal loss Swarm onboard receivers. Our results show that losses prefer occur at both low latitudes between ±5 and ±20∘ magnetic latitude (MLAT) high above 60∘ MLAT hemispheres. These events all are observed mainly during equinoxes solstice months, while totally absent June months. At caused by equatorial plasma...
Abstract In this study, we provide for the first time observation of latitudinal four‐peak structure F region electron density in nightside ionosphere. The special configuration Swarm satellites, B having chance to resample regions A/C with successively increasing differences, provides an unprecedented opportunity check evolution these peaks. Overall, structures have very low occurrence rates, only 4% orbits. two mid‐latitude peaks prefer appear close ±40° magnetic latitude, while...
Key Points Two clearly different systems of IHFACs exist at low and middle latitudes, respectively, with a boundary near ±35° in magnetic latitudes The latitudinal longitudinal structures depend strongly on wave forcing from the lower atmosphere, below 30 km Midlatitude have similar climatology equinoxes/June solstice, while those December solstice exhibit behavior
Abstract Low‐latitude plasma blobs have been studied since their first being reported in 1986. However, investigations on temporal evolution of a blob or continental scale (>2,000 km) ionospheric contexts around it are relatively rare. Overcoming these limitations can help elucidate the generation mechanisms. On 21 January 2021, Ionospheric Connection Explorer satellite encountered typical low‐latitude near northeastern coast South America. The event was collocated with local enhancement...
The 27‐day solar modulation of the low‐latitude ionosphere is investigated for maximum period using in situ satellite measurement data and total electron contents (TEC) estimated from signals global positioning system (GPS). Whereas density temperature topside observed at an altitude 685 km manifest delayed responses to variations daily F10.7 values, similar those previously reported 840 km, nighttime‐scale height, obtained by comparing densities altitudes local times, was shown vary...
Using magnetic field observations of the CHAMP satellite we provide first comprehensive study F ‐region dynamo currents as a function season, local time, geographic longitude, and solar activity. From bipolar variations zonal component density vertical current driven by is deduced. The strength smallest around June solstice, which attributed to reduced Pedersen conductance caused lower electron neutral at that season. During hours noon highest densities are observed. They flowing downward...
Abstract. Field-aligned currents (FACs) generate magnetic deflections perpendicular to the ambient Earth field. We investigate characteristics of FACs associated with equatorial plasma bubbles (EPBs) as deduced from field measurements by CHAMP satellite. Meridional inside EPBs show a clear hemispheric anti-symmetry for events observed before 21:00 LT: inward in Northern Hemisphere and outward Southern Hemisphere. When an eastward electric is assumed signature signifies Poynting flux directed...
Equatorial spread-F ionospheric plasma irregularities on the night-side, commonly called equatorial bubbles (EPB), include electron density variations over a wide range of spatial scales. Here we focus intermediate-scale structures ranging from 100 m to 10 km, which play an important role in evolution EPBs. High-resolution CHAMP magnetic field measurements sampled along north-south track at 50 Hz are interpreted terms diamagnetic effect for illustrating details variations. We provide first...
Abstract The European Space Agency's Swarm constellation can measure electric field, magnetic and plasma density on board multiple satellites at altitudes of about 500 km. Based the data set high latitudes, we estimate Poynting flux ionospheric reflection coefficients Alfvén waves with scale sizes 10–100 are generally higher surrounding cusp auroral regions than in polar cap summer winter hemisphere. In (winter) hemisphere peak dayside (nightside). Distributions not controlled by those situ...
Abstract We report the preliminary inter-satellite comparisons of in situ ion density measurements by velocity meter (IVM) onboard FORMOSAT-7/COSMIC-2 (F7/C2) and Ionospheric Connection Explorer (ICON) missions, during solar minimum period December 2019 to November 2020. The initial reveal identical diurnal, seasonal, latitude/longitude variations two ion-density measurements, with F7/C2 consistently yielding stronger values than ICON, which could partly result from difference their orbit...
The ionosphere, Earth's space environment, exhibits widespread turbulent structuring, or plasma irregularities, visualized by the auroral displays seen in polar regions. Such irregularities have been studied for decades, but turbulence remains an elusive phenomenon. We combine scale-dependent measurements from a ground-based radar with satellite observations to characterize small-scale simultaneously bottomside and topside ionosphere perform statistical analysis on aggregate both instruments...