A5038361096- Ionosphere and magnetosphere dynamics
- Solar and Space Plasma Dynamics
- Geomagnetism and Paleomagnetism Studies
- Earthquake Detection and Analysis
- Astro and Planetary Science
- GNSS positioning and interference
- Geophysics and Gravity Measurements
- Planetary Science and Exploration
- Magnetic confinement fusion research
- Distributed and Parallel Computing Systems
- Atmospheric Ozone and Climate
- Astrophysics and Cosmic Phenomena
- Scientific Computing and Data Management
- Research Data Management Practices
- Space Exploration and Technology
- Big Data Technologies and Applications
- Meteorological Phenomena and Simulations
- Computational Physics and Python Applications
- Space exploration and regulation
- Complex Systems and Time Series Analysis
- Spacecraft and Cryogenic Technologies
- Laser-induced spectroscopy and plasma
- Atomic and Subatomic Physics Research
- Lightning and Electromagnetic Phenomena
- Plasma Diagnostics and Applications
Goddard Space Flight Center
2014-2024
Heliophysics
2008-2024
Auburn University
2023
DigitalSpace (United States)
2023
Heliophysics Science Division
2011-2019
Space Physics Data Facility
1997-2011
University of Maryland, College Park
1997-2011
Jensen Hughes (United States)
1997
University of Alaska Fairbanks
1997
Professional Services Group (United States)
1992
The origin of whistler mode radiation in the plasmasphere is examined from 3 years plasma wave observations Dynamics Explorer and Imager for Magnetopause‐to‐Aurora Global Exploration spacecraft. These data are used to construct intensity maps plasmasphere. highest average intensities show source locations and/or sites amplification. Each type classified on basis its magnetic latitude longitude rather than any spectral feature. Equatorial electromagnetic (EM) emissions (∼30–330 Hz),...
Reconnection is accepted as an important process for driving the solar wind/magnetospheric interaction although it not fully understood. In particular, reconnection northward interplanetary magnetic field (IMF) at high‐latitudes tailward of cusp, has received little attention in comparison with equatorial southward IMF. Using Hawkeye data we present first direct observations high‐latitude magnetopause (75°) during IMF form sunward flowing protons. This flow nearly aligned, approximately...
On 15 October 1981 Dynamics Explorer 2 crossed the polar cusp at 1015 MLT and observed three distinct ion populations as it was moving poleward. These had peak‐flux energy around 2.7 keV, 850 eV 360 eV. At time of observation, IMF southward. The first step coincided with a rotation flow from westward to poleward then eastward. second third steps showed directed principally Furthermore, magnetic electric perturbations in are well fitted by an elongated flux tube footprint model. results...
For decades, observations of Faraday rotation have provided unique insights into the plasma density and magnetic field structure solar wind. (FR) is plane polarization when linearly polarized radiation propagates through a magnetized plasma, such as corona, coronal mass ejection (CME), or stream interaction region. FR measurements are very versatile: they provide deeper understanding large-scale over range heliocentric distances (especially <mml:math...
A new technique is introduced that remotely measures the plasma density profile in plasmasphere. Radio imager (RPI) echo observations provide delay time as function of frequency, from which position along magnetic field line can be calculated. An example nightside plasmasphere (L=3) shows having its minimum value near equator and rapidly increasing densities above 40° latitude. The increases at a faster rate toward ionosphere than strength. index power law strength few tenths to close unity...
Using the sounding measurements from radio plasma imager on IMAGE and a density inversion algorithm, we derive profiles along magnetic field in few L shells every 14 hours at local noon before, during, after 31 March 2001 storm. An empirical model of plasmaspheric distribution is derived as reference using before During storm equatorial was substantially depleted range shells. The flux tubes were refilled filling ratio, normalized by its quiet time value storm, introduced to assess evolution...
Abstract Solitary magnetic structures known as SLAMS (short large‐amplitude structures) have been considered essential elements of collisionless shocks with quasi‐parallel geometries. Yet the physics underlying their formation remains an open question. In this paper, we use measurements from magnetospheric multiscale mission combined fully kinetic simulations to study SLAMS. We find that gyro‐resonance between solar wind ions and right‐hand circularly polarized electromagnetic waves results...
The first empirical model of the equatorial mass density plasmasphere is constructed using ground‐based ULF wave diagnostics. Plasmaspheric between L = 1.7 and 3.2 has been determined over 5200 hours data from pairs stations in MEASURE array ground magnetometers. least squares fit to as a function shows that falls logarithmically with . Average ion also estimated by combining plasmaspheric electron profiles IMAGE Radio Plasma Imager (RPI). Additionally, we use RPI database examine how...
Progress in space weather research and awareness needs community-wide strategies procedures to evaluate our modeling assets. Here we present the activities of Ambient Solar Wind Validation Team embedded COSPAR ISWAT initiative. We aim bridge gap between model developers end-users provide community with an assessment state-of-the-art solar wind forecasting. To this end, develop open online platform for validating models by comparing their solutions situ spacecraft measurements. The will allow...
The Radio Plasma Imager (RPI) is a 3 kHz to MHz radio sounder, incorporating modern digital processing techniques and long electronically‐tuned antennas, that flown large radial distances into the high‐latitude magnetosphere on for Magnetopause‐to‐Aurora Global Exploration (IMAGE) satellite. Clear echoes, similar those observed by ionospheric topside sounders, are routinely from polar‐cap ionosphere RPI even when IMAGE located at geocentric up approximately 5 Earth radii. Using an inversion...
Among the objectives of Radio Plasma Imager (RPI) on IMAGE is observation Earth's plasmasphere from satellite's polar orbit, with apogee ≈8 R E geocentric distance and perigee near 1200 km altitude. This objective here pursued by (1) remote sounding high‐altitude regions outside main plasmasphere, (2) within (3) in situ passive measurements natural wave activity. During both inside plasmapause, RPI echoes that follow non‐field‐aligned ray paths are usually not discrete traces...
[1] Simultaneous observations by Cluster and Los Alamos National Laboratory (LANL) spacecraft Canadian Array for Real-Time Investigations of Magnetic Activity International Monitor Auroral Geomagnetic Effects magnetometer arrays during a sudden storm commencement on 25 September 2001 show evidence relativistic electron acceleration compressional-mode ULF waves. The waves are driven the quasiperiodic solar wind dynamical pressure fluctuations that continuously buffet magnetosphere ∼3 h....
Abstract Global observations of He + ions from the Imager for Magnetopause‐to‐Aurora Exploration mission Extreme Ultraviolet are used to examine dynamics plasmasphere content using integrated mass through times erosion and refilling . Perhaps most basic important attributes its spatial distribution. However, our understanding is often constrained by method measurement. Storm‐time loss a kind exhalation where plasma lost. Refilling or inhalation into body occurs during following calm. Using...
We report comprehensive statistical results for 4 years of Hawkeye observations totaling 1757 boundary crossings. Our objective is to use the full set plasma, magnetic field, and plasma wave data identify every cusp‐associated interval (entry layer, cusp, mantle), spatially map these regions, isolate primary variables affecting their occurrence frequency location. find that SM coordinates best order angular position cusp region intervals GSM are better ordering in radial distance, especially...
Abstract. We show a clear correlation between the ULF wave power (Pc5 range) inside and outside Earth's magnetosphere during high speed streams in 1995. trace fluctuations beginning 200RE upstream using Wind data, to just from bow shock magnetosheath Geotail data compare pulsations on ground at Kilpisjarvi station. With our 5-month set we draw following conclusions. Pc5 range are found streams; they non-Alfvénic leading edge Alfvénic central region. Compressional modulated shock, some...
Magnetic field, electric field and energetic electron measurements from CRRES, GOES‐6 ‐7 satellites are used to investigate the production of up 2 MeV fluxes through a storm sudden commencement (SSC) event on August 27, 1991. Strong Pc‐5 oscillations, whose is mainly along radial direction, an order‐of‐magnitude enhancement in relativistic occurred simultaneously two‐hour period. The enhanced found have pancake‐like pitch angle distribution, which consistent with being accelerated near...
Abstract The Space Physics Archive Search and Extract Consortium has developed implemented the SPASE Data Model that provides a common language for registering wide range of Heliophysics data other products. enables discovery access tools such any researcher can obtain easily, thereby facilitating research, including on space weather. includes descriptions Simulation Models Numerical Output, pioneered by Integrated Medium Planetary Exploration (IMPEx) group in Europe, subsequently adopted...
Over the past 10 years, a paradigm shift has happened in world of science and information technology. Open is becoming de facto standard, as underlined by recent recommendation on Science approved United Nations Educational, Scientific Cultural Organization (UNESCO) November 2021. In parallel, artificial intelligence (AI) machine learning (ML) technologies are already part our daily life, profoundly impacting societies. This reality far different from when 2015-2025 COmmittee SPAce Research...
Electron density N e distributions in the northern polar region are determined from 1.4 to 5.0 R E at invariant latitudes greater than 70° using radio plasma imager (RPI) on IMAGE satellite over period June 2000 November 2001. An empirical model this is derived as a function of radial distance and geomagnetic activity. A power law with index −5.09 ± 0.03 describes variation distance. The appears increase exponentially Kp index. altitude dependence low activity qualitatively consistent...
Several year's worth of observations from the plasma wave instruments on both Magnetopause‐to‐Aurora Global Exploration (IMAGE) and Polar spacecraft are used to study seasonal solar cycle variations in spectrum auroral kilometric radiation (AKR). Only AKR when were Northern Hemisphere emission cones used. The results analysis show significant changes as a function dipole tilt. average spectral peak for positive tilt is ∼150 kHz but ∼300 during times negative In addition, up two orders...