A5100767178- Ionosphere and magnetosphere dynamics
- Solar and Space Plasma Dynamics
- Earthquake Detection and Analysis
- Geomagnetism and Paleomagnetism Studies
- Geophysics and Gravity Measurements
- Radiation Therapy and Dosimetry
- Astro and Planetary Science
- Spacecraft Design and Technology
- GNSS positioning and interference
- Radiation Detection and Scintillator Technologies
- Space Satellite Systems and Control
- Atmospheric Ozone and Climate
- Planetary Science and Exploration
- Satellite Communication Systems
- Space exploration and regulation
- Nuclear Physics and Applications
- Disaster Management and Resilience
- Advanced Radiotherapy Techniques
- Gamma-ray bursts and supernovae
- Oil, Gas, and Environmental Issues
- Radiation Dose and Imaging
- Precipitation Measurement and Analysis
- Meteorological Phenomena and Simulations
- Dust and Plasma Wave Phenomena
- Radio Astronomy Observations and Technology
Korea Astronomy and Space Science Institute
2014-2024
Korea Aerospace Research Institute
2022
Korea University of Science and Technology
2009-2021
Korea University
2019
University of California, Berkeley
2006
Korea Advanced Institute of Science and Technology
1998-2002
While numerous anomalies and failures of spacecraft have been reported since the beginning space age, weather effects on modern systems emphasized more with increase their complexity capability. However, relationship between commercial satellite has not studied extensively. In this paper, we investigate geostationary Earth orbit (GEO) archived by Satellite News Digest during 1997–2009 in order to search for possible influences anomaly occurrences. We analyze Kp index, local time, season then...
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...
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...
We present the first simultaneous observations of so-called "hot explosions" in cool atmosphere Sun made by New Solar Telescope (NST) Big Bear Observatory and Interface Region Imaging Spectrograph (IRIS) space. The data were obtained during joint IRIS-NST on 2014 July 30. explosion interest started around 19:20 UT lasted for about 10 minutes. Our findings are as follows: (1) IRIS brightening was observed three channels slit-jaw images, which cover temperature range from 4000 to 80,000 K; (2)...
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...
Abstract It is well known that electromagnetic ion cyclotron (EMIC) waves play an important role in controlling particle dynamics inside the Earth's magnetosphere, especially outer radiation belt. In order to understand results of wave‐particle interactions due EMIC waves, it know how are distributed and what features they have. this paper, we present some statistical analyses on spatial distribution low Earth orbit by using Swarm satellites from December 2013 June 2017 (~3.5 years) as a...
Abstract Low Earth orbit satellites frequently encounter Pc1 pulsations, but most have been observed with limited latitudinal extent or short lifetime. In this study we analyze two large‐scale pulsations (both latitudinally wide and long‐lasting) generated by ionospheric ducting effect using Swarm ground magnetometers on 25 June 3 September 2015. the both dayside nightside during storm time substorm (a strong geomagnetic 23 D st = − 204 nT ). We found were pervasive in magnetic local sectors...
Abstract The rapid increase of electron temperature in the early morning hours at low latitudes is a well‐known ionospheric phenomenon called overshoot. In this study, we extensively investigate dependence overshoot on local time, season, latitude/longitude/altitude, and magnetic activity. density data set used study are obtained from (1) Swarm constellation two different altitudes 470 520 km with identical payloads (2) Floating Potential Measurement Unit onboard International Space Station...
While the ion and electron temperatures inside equatorial plasma bubbles (EPBs) are normally lower than those in an ambient plasma, with enhanced (BETs) found occasionally topside ionosphere. Here we report characteristics of BETs identified from observations first Republic China Satellite (ROCSAT‐1), Korea Multi‐purpose (KOMPSAT‐1), Defense Meteorological Program (DMSP) F15 during solar maximum period between 2000 2001. The oxygen fraction BETs, which was no that ionosphere, similar to case...
In this paper, an operational Dst index prediction model is developed by combining empirical and Artificial Neural Network (ANN) models. ANN algorithms are widely used to predict space weather conditions. While they require a large amount of data for machine learning, large-scale geomagnetic storms have not occurred sufficiently the last 20 years, Advanced Composition Explorer (ACE) Deep Space Climate Observatory (DSCOVR) mission operation period. Conversely, models based on numerical...
Abstract Accurate knowledge of the global distribution magnetospheric chorus waves is essential for radiation belt modeling because it provides a direct link to understanding losses and acceleration processes. In this paper, we report on newly developed models amplitudes based in situ measurements interplanetary magnetic field (IMF) solar wind parameters as well geomagnetic indices using an artificial neural network technique. We find that speed IMF B Z are most influential affect evolution...
Abstract The whistler anisotropy (or electromagnetic electron cyclotron) instability may be operative in many geomagnetic and heliospherical environments, including the radiation belt, solar wind, corona. present investigation carries out a comparative analysis between two‐dimensional particle‐in‐cell simulation of weakly growing velocity moment‐based quasi‐linear theory under assumption bi‐Maxwellian distribution function. It is shown that simplified provides qualitative agreement with more...
This study was performed by the policy research project of Ministry Land, Transport and Maritime Affairs, which title is "Developing safety standards management space radiation on polar route". In this research, total six experiments were using Korean commercial flights (B747). Three those are route other three north pacific route. Space exposure measured average 84.7 uSv. The simulation result CARI-6M program gives 84.9 uSv, very similar to value. For departure flight route, 74.4 It seems...
Small-scale magNetosphere and Ionosphere Plasma Experiment (SNIPE) mission is aimed to observe a small-scale structure of the physical phenomena in near-Earth environment. SNIPE comprises four 6U size nanosats that perform formation flying meet scientific objectives mission. In this study, we designed system validated it using numerical simulations collect temporal spatial differences for The requirements spacecraft are pass same point at different times be located longitude points on...
We present preliminary observations of the field-aligned-irregularities (FAIs) in E and F regions during solar minimum (2009 - 2010) using 40.8 MHz coherent backscatter radar at Daejeon (<TEX>$36.18^{\circ}N$</TEX>, <TEX>$127.14^{\circ}E$</TEX>, <TEX>$26.7^{\circ}N$</TEX> dip latitude) South Korea. The radar, which consists 24 Yagi antennas, observes FAIs a single beam with peak power kW. has been continuously operated since December 2009. Depending on manner occurrence echoes, E-region...
Abstract The temporal variations in cosmic radiation on aircraft under constant flight conditions were measured by a Liulin detector. Rather than commercial long‐distance aircraft, we used military reconnaissance performing circular at altitude over the Korean Peninsula. At 9144 m (30,000 ft), mean and standard deviation of dose rate (among 35 measurements) was 2.3 0.17 μSv/h, respectively. experiment yielded two observational results. First, changed time 5–7 h; second, no strong correlation...
Abstract Multiple‐harmonic electron cyclotron emissions, often known in the literature as ( n + 1/2) f ce are a common occurrence magnetosphere. These emissions interpreted terms of Bernstein mode instability driven by loss cone velocity distribution function. Alternatively, they can be quasi‐thermal emission electrostatic fluctuations magnetized plasmas. The present paper carries out one‐dimensional relativistic electromagnetic particle‐in‐cell simulation and also employs reduced...
The Korean Solar Radio Burst Locator (KSRBL) is a solar radio spectrograph observing the broad frequency range from 0.245 to 18 GHz with capability of locating wideband gyrosynchrotron bursts. Due characteristics spiral feed, beam center varies in pattern frequency, making modulation over spectrum. After calibration process, we obtained dynamic spectra consistent Nobeyama Polarimeter (NoRP). We compared and analyzed locations bursts observed by KSRBL results Radioheliograph (NoRH)...
The Small Scale magNetospheric and Ionospheric Plasma Experiment (SNIPE)'s scientific goal is to observe spatial temporal variations of the micro-scale plasma structures on topside ionosphere. four 6U CubeSats (~10 kg) will be launched into a polar orbit at ~500 km. distances each satellite controlled from 10 km more than ~1,000 by formation flying algorithm. SNIPE mission equipped with identical instruments, Solid-State Telescopes(SST), Magnetometers(Mag), Langmuir Probes(LP). All payloads...
Abstract In this paper, we statistically investigate an artifact in Langmuir Probe (LP) observations of Swarm satellites. A small peak electron density ( N e ) is frequently found the data around dayside dip equator. On contrary, they appear neither Total Electron Content Swarm/Global Positioning System Receivers nor COSMIC‐2 in‐situ measurements at similar altitudes but with low orbit inclination. Arguably, does not represent natural ionospheric irregularities likely to result from...