A5085642855- Geomagnetism and Paleomagnetism Studies
- Geophysics and Gravity Measurements
- Geophysical and Geoelectrical Methods
- Planetary Science and Exploration
- Earthquake Detection and Analysis
- Astro and Planetary Science
- Solar and Space Plasma Dynamics
- Ionosphere and magnetosphere dynamics
- Cryospheric studies and observations
- Geological and Geophysical Studies
- Inertial Sensor and Navigation
- Geology and Paleoclimatology Research
- GNSS positioning and interference
- Scientific Research and Discoveries
- Arctic and Antarctic ice dynamics
- Space Science and Extraterrestrial Life
- Space Exploration and Technology
- Atmospheric and Environmental Gas Dynamics
- Methane Hydrates and Related Phenomena
- Gamma-ray bursts and supernovae
- Oceanographic and Atmospheric Processes
- Geochemistry and Geologic Mapping
- High-pressure geophysics and materials
- Spacecraft and Cryogenic Technologies
- Reservoir Engineering and Simulation Methods
Goddard Space Flight Center
2013-2025
University of Maryland, Baltimore County
2020
Deleted Institution
2005-2017
RTX (United States)
2000-2014
Planetary Science Institute
2013
Planetary Systems (United States)
2010
Continental (United States)
2006
National Oceanic and Atmospheric Administration
2005
Jensen Hughes (United States)
1992-1997
Applications Research (United States)
1989
The 12th generation of the International Geomagnetic Reference Field (IGRF) was adopted in December 2014 by Working Group V-MOD appointed Association Geomagnetism and Aeronomy (IAGA). It updates previous IGRF with a definitive main field model for epoch 2010.0, 2015.0, linear annual predictive secular variation 2015.0-2020.0. Here, we present equations defining model, provide spherical harmonic coefficients, maps magnetic declination, inclination, total intensity 2015.0 their predicted rates...
The eleventh generation of the International Geomagnetic Reference Field (IGRF) was adopted in December 2009 by Association Geomagnetism and Aeronomy (IAGA) Working Group V-MOD.It updates previous IGRF with a definitive main field model DGRF 2005.0, for 2010.0, linear predictive secular variation 2010.0-2015.0.In this note equations defining are provided together spherical harmonic coefficients generation.Maps magnetic Declination, Inclination Total Intensity epoch 2010.0 their predicted...
Abstract In December 2019, the International Association of Geomagnetism and Aeronomy (IAGA) Division V Working Group (V-MOD) adopted thirteenth generation Geomagnetic Reference Field (IGRF). This IGRF updates previous with a definitive main field model for epoch 2015.0, 2020.0, predictive linear secular variation 2020.0 to 2025.0. letter provides equations defining IGRF, spherical harmonic coefficients this model, maps magnetic declination, inclination total intensity their predicted rate...
Abstract We have determined the ice mass evolution of Antarctic and Greenland sheets (AIS GIS) Gulf Alaska (GOA) glaciers from a new GRACE global solution equal-area surface concentration parcels (mascons) in equivalent height water. The mascons were estimated directly reduction inter-satellite K-band range-rate (KBRR) observations, taking into account full noise covariance, formally iterating solution. increases signal recovery while reducing KBRR observation residuals. with 10 day 1 arcdeg...
A new model of the quiet-time, near-Earth magnetic field has been derived using a comprehensive approach, which includes not only POGO and Magsat satellite data, but also data from Ørsted CHAMP satellites. The resulting shows great improvement over its predecessors in terms completeness sources, time span noise reduction parameters. With well separated fields extended domain 1960 to mid-2002, is able detect known sequence geomagnetic jerks within this frame gives evidence for an event...
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...
Observations from the Gravity Recovery and Interior Laboratory (GRAIL) mission indicate a marked change in gravitational signature of lunar impact structures at morphological transition, with increasing diameter, complex craters to peak-ring basins. At crater diameters larger than ~200 km, central positive Bouguer anomaly is seen within innermost peak ring, an annular negative extends outward this ring outer topographic rim crest. These observations demonstrate that basin-forming impacts...
Abstract We have derived a gravity field solution in spherical harmonics to degree and order 900, GRGM900C, from the tracking data of Gravity Recovery Interior Laboratory (GRAIL) Primary (1 March 29 May 2012) Extended Missions (30 August 14 December 2012). A power law constraint 3.6 ×10 −4 / ℓ 2 was applied only for greater than 600. The model produces global correlations gravity, predicted lunar topography ≥ 0.98 through 638. model's strength varies minimum 575–675 over central nearside...
We present CHAOS-4, a new version in the CHAOS model series, which aims to describe Earth's magnetic field with high spatial and temporal resolution. Terms up spherical degree of at least n = 85 for lithospheric field, 16 time-varying core are robustly determined. More than 14 yr data from satellites Ørsted, CHAMP SAC-C, augmented observatory monthly mean values have been used this model. Maximum harmonic static (lithospheric) is 100. The expressed by expansion coefficients 20; its...
We have derived a model of the near-Earth magnetic field (up to spherical harmonic degree n= 50 for static field, and up 18 first time derivative) using more than 6.5 yr high-precision geomagnetic measurements from three satellites Ørsted, CHAMP SAC-C taken between 1999 March 2005 December. Our modelling approach goes in several aspects beyond that used recent models: (i) we use different data selection criteria allow higher activity (index Kp≤ 2o), thus include previous models; (ii)...
The near-Earth magnetic field is caused by sources in the Earth's core, ionosphere, magnetosphere, lithosphere and from coupling currents between ionosphere hemispheres. Traditionally, main (low degree internal field) magnetospheric have been modelled simultaneously, with fields other being separately. Such a scheme, however, can introduce spurious features, especially when spatial temporal scales of overlap. A new model, designated CM3 (Comprehensive Model: phase 3), third series efforts to...
A comprehensive magnetic field model named CM5 has been derived from CHAMP, Ørsted and SAC-C satellite observatory hourly-means data 2000 August to 2013 January using the Swarm Level-2 Comprehensive Inversion (CI) algorithm. is a recently launched constellation of three satellites map Earth's field. The CI technique includes several interesting features such as bias mitigation scheme known Selective Infinite Variance Weighting (SIVW), new treatment for attitude error in vector measurements,...
We investigate the spatiotemporal behavior of magnetic vertical component, Z, daily ionospheric current systems: equatorial electrojet (EEJ) and solar quiet (Sq) variations, considering induction in mantle oceans. The inducing EEJ Sq systems are provided by comprehensive model Sabaka et al. (2004). three‐dimensional (3‐D) conductivity Earth includes oceans laterally variable conductance a spherical conductor (1‐D) underneath. Our studies demonstrate that effects Z due to negligible...
Abstract We have analyzed Ka‒band range rate (KBRR) and Deep Space Network (DSN) data from the Gravity Recovery Interior Laboratory (GRAIL) primary mission (1 March to 29 May 2012) derive gravity models of Moon degree 420, 540, 660 in spherical harmonics. For these models, GRGM420A, GRGM540A, GRGM660PRIM, a Kaula constraint was applied only beyond 330. Variance‒component estimation (VCE) used adjust priori weights obtain calibrated error covariance. The global root‒mean‒square anomalies...
The differences between mass concentration (mascon) parameters and standard Stokes coefficient in the recovery of gravity information from climate experiment (GRACE) intersatellite K‐band range rate data are investigated. First, mascons decomposed into their representations to gauge solutions available using each two types parameters. Next, a direct comparison is made time series unconstrained solutions, one based on set global equal area mascon (equivalent 4° × at equator), other...
Geodetic analysis of radio tracking measurements the MESSENGER spacecraft while in orbit about Mercury has yielded new estimates for planet's gravity field, tidal Love number, and pole coordinates. The derived right ascension (α = 281.0082° ± 0.0009°; all uncertainties are 3 standard deviations) declination (δ =61.4164° 0.0003°) spin place Cassini state. Confirmation equilibrium state with an estimated mean (whole-planet) obliquity ϵ 1.968 0.027 arcmin enables confident determination...
We present a new global electrical conductivity model of Earth's mantle. The was derived by using novel methodology, which is based on inverting satellite magnetic field measurements from different sources simultaneously. Specifically, we estimated responses magnetospheric origin and ocean tidal signals the most recent Swarm CHAMP data. challenging task properly accounting for effect in data addressed through full three-dimensional solution Maxwell's equations. show that simultaneous...
Knowledge of the average density crust a planet is important in determining its interior structure. The combination high-resolution gravity and topography data has yielded low for Moon's crust, yet other terrestrial planets resolution field models hampered reasonable estimates. By using well-chosen constraints derived from during model determination satellite tracking data, we show that can robustly independently determine bulk crustal directly admittance between imperfect gravity. We find...
Abstract From the launch of Ørsted satellite in 1999, through CHAMP mission from 2000 to 2010, and now with Swarm constellation starting 2013, magnetometry has provided excellent monitoring near-Earth magnetic field regime. The advanced Comprehensive Inversion scheme been applied data before itself, but for first time all this new era, culminating CM6 model. highlights model include not only a continuous core description over entire period 1999 2019.5 good agreement CHAOS series, addition...
Techniques developed for the reduction and analysis of terrestrial satellite magnetic field data are used to better understand observations made by Mars Global Surveyor. A global distribution radial ( B r ) associated uncertainties is inverted an equivalent source magnetization then generate altitude‐normalized map at 200 km. The well‐represented a potential function crustal origin, consistent with remanent origin Martian features. correlation between 40546 calculated from solution...
Magnetic measurements taken by the Ørsted satellite during geomagnetic quiet conditions around January 1, 2000 have been used to derive a spherical harmonic model of Earth's magnetic field for epoch 2000.0. The maximum degree and order is 19 internal, 2 external, source fields; however, coefficients above 14 may not be robust. Such detailed exists only one previous epoch, 1980. Achieved rms misfit <2 nT scalar intensity <3 vector components perpendicular field. For scientific purposes...