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GRACE-FO radiation pressure modelling for accurate density and crosswind retrieval

Hladczuk, N.A. (author), van den IJssel, J.A.A. (author), Kodikara, T. (author), Siemes, C. (author), Visser, P.N.A.M. (author)

Uncertainties in radiation pressure modelling play a significant role in the thermospheric density and crosswind observations derived from the GRACE-FO accelerometer, especially during low solar activity. Under such conditions, the radiation pressure acceleration matches the magnitude of the aerodynamic acceleration along the track and...

journal article 2024

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Uncertainty of thermosphere mass density observations derived from accelerometer and GNSS tracking data

Siemes, C. (author), van den IJssel, J.A.A. (author), Visser, P.N.A.M. (author)

Thermosphere mass density and crosswind can be derived from accelerometer and GNSS tracking data. However, present datasets are often provided without comprehensive uncertainty specifications. We present a newly developed method that propagates measurement noise and errors in the satellite specification, thermosphere models, and radiation flux...

journal article 2024

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Topside Ionosphere Sounding From the CHAMP, GRACE, and GRACE-FO Missions

Schreiter, Lucas (author), Stolle, Claudia (author), Rauberg, Jan (author), Kervalishvili, Guram (author), van den IJssel, J.A.A. (author), Arnold, Daniel (author), Xiong, Chao (author), Callegare, Andyara (author)

Satellites in Low Earth Orbit (LEO) are essential for sounding the topside ionosphere. In this work, we present and validate a data set of Total Electron Content (TEC) and in situ electron density observations from the Gravity Recovery And Climate Experiment (GRACE) and GRACE-Follow-On missions as well as a TEC data set from the CHAllenging...

journal article 2023

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New thermosphere neutral mass density and crosswind datasets from CHAMP, GRACE, and GRACE-FO

Siemes, C. (author), Borries, Claudia (author), Bruinsma, S. (author), Fernandez-Gomez, I. (author), Hladczuk, N.A. (author), van den IJssel, J.A.A. (author), Kodikara, T. (author), Vielberg, K. (author), Visser, P.N.A.M. (author)

We present new neutral mass density and crosswind observations for the CHAMP, GRACE, and GRACE-FO missions, filling the last gaps in our database of accelerometer-derived thermosphere observations. For consistency, we processed the data over the entire lifetime of these missions, noting that the results for GRACE in 2011- 2017 and GRACE-FO...

journal article 2023

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Interhemispheric Asymmetry of the Thermospheric Neutral Density Response to the 7–9 September 2017 Geomagnetic Storms

Zhu, Qingyu (author), Lu, Gang (author), Lei, Jiuhou (author), Deng, Yue (author), Doornbos, E.N. (author), van den IJssel, J.A.A. (author), Siemes, C. (author)

The thermospheric neutral density response to the 7–9 September 2017 storms is investigated based on the Swarm satellite observations and the thermosphere-ionosphere-electrodynamic general circulation model (TIEGCM) simulation. The Swarm data depicted a prominent interhemispheric asymmetry (IHA) in the afternoon sector during the second storm...

journal article 2023

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Dayside Upper-Thermospheric Density Fluctuations as Observed by GRACE and GRACE-FO at ∼500 km Height

Park, Jaeheung (author), van den IJssel, J.A.A. (author), Siemes, C. (author)

We statistically investigate fluctuation amplitudes (normalized to the background values) of dayside low-/mid-latitude upper-thermospheric mass density as observed by the Gravity Recovery and Climate Experiment (GRACE) and GRACE-Follow-On (GRACE-FO) spacecraft at ∼500 km altitude between 2002 and 2022. There are three new findings in our...

journal article 2023

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Daedalus MASE (mission assessment through simulation exercise): A toolset for analysis of in situ missions and for processing global circulation model outputs in the lower thermosphere-ionosphere

Sarris, Theodore E. (author), Tourgaidis, Stelios (author), Pirnaris, Panagiotis (author), Baloukidis, Dimitris (author), Papadakis, Konstantinos (author), Doornbos, Eelco (author), Siemes, C. (author), Visser, P.N.A.M. (author), van den IJssel, J.A.A. (author)

Daedalus MASE (Mission Assessment through Simulation Exercise) is an open-source package of scientific analysis tools aimed at research in the Lower Thermosphere-Ionosphere (LTI). It was created with the purpose to assess the performance and demonstrate closure of the mission objectives of Daedalus, a mission concept targeting to perform in...

journal article 2023

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CASPA-ADM: a mission concept for observing thermospheric mass density

Siemes, C. (author), Maddox, Stephen (author), Carraz, Olivier (author), Cross, Trevor (author), George, Steven (author), van den IJssel, J.A.A. (author), Kiss-Toth, Marton (author), Pastena, Massimiliano (author), Visser, P.N.A.M. (author)

Cold Atom technology has undergone rapid development in recent years and has been demonstrated in space in the form of cold atom scientific experiments and technology demonstrators, but has so far not been used as the fundamental sensor technology in a science mission. The European Space Agency therefore funded a 7-month project to define the...

journal article 2022

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Exospheric Temperature Measured by NASA-GOLD Under Low Solar Activity: Comparison With Other Data Sets

Park, Jaeheung (author), Evans, Joseph S. (author), Eastes, Richard W. (author), Lumpe, Jerry D. (author), van den IJssel, J.A.A. (author), Englert, Christoph R. (author), Stevens, Michael H. (author)

Exospheric temperature is one of the key parameters in constructing thermospheric models and has been extensively studied with in situ observations and remote sensing. The Global-scale Observations of the Limb and Disk (GOLD) at a geosynchronous vantage point provides dayglow limb images for two longitude sectors, from which we can estimate...

journal article 2022

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A Novel Method to Derive Exospheric Temperatures from Swarm Thermospheric Densities during Quiet Times

Lin, Yingyun (author), Xu, Jiyao (author), van den IJssel, J.A.A. (author), Yuan, Wei (author)

One of the most important parameters in the atmosphere, the neutral temperature, becomes difficult to measure at high altitudes such as the exosphere. Therefore, based on the assumption of static equilibrium and isothermal atmosphere, a new method was developed to derive quiet-time exospheric temperatures using neutral atmospheric densities from...

journal article 2022

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Gas-surface interactions modelling influence on satellite aerodynamics and thermosphere mass density

March, G. (author), van den IJssel, J.A.A. (author), Siemes, C. (author), Visser, P.N.A.M. (author), Doornbos, Eelco N. (author), Pilinski, Marcin (author)

The satellite acceleration data from the CHAMP, GRACE, GOCE, and Swarm missions provide detailed information on the thermosphere density over the last two decades. Recent work on reducing errors in modelling the spacecraft geometry has greatly reduced scale differences between the thermosphere data sets from these missions. However, residual...

journal article 2021

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Lower-Thermosphere-ionosphere (LTI) quantities: Current status of measuring techniques and models

Palmroth, Minna (author), Grandin, Maxime (author), Sarris, Theodoros (author), Doornbos, Eelco (author), Tourgaidis, Stelios (author), March, G. (author), Siemes, C. (author), van den IJssel, J.A.A. (author), Visser, P.N.A.M. (author)

<p>The lower-Thermosphere-ionosphere (LTI) system consists of the upper atmosphere and the lower part of the ionosphere and as such comprises a complex system coupled to both the atmosphere below and space above. The atmospheric part of the LTI is dominated by laws of continuum fluid dynamics and chemistry, while the ionosphere is a plasma...

journal article 2021

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Two-Dimensional Reconstruction of Ionospheric Plasma Density Variations Using Swarm

Fæhn Follestad, A. (author), Clausen, L. B.N. (author), Miloch, W. J. (author), van den IJssel, J.A.A. (author), Haagmans, R. (author)

Space weather phenomena such as scintillations of Global Navigation Satellite Systems (GNSS) signals are of increasing importance for aviation, the maritime, and civil engineering industries. The ionospheric plasma irregularities causing scintillations are associated with strong gradients in ionospheric plasma density. To provide nowcasts and...

journal article 2020

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On the Occurrence of GPS Signal Amplitude Degradation for Receivers on Board LEO Satellites

Xiong, Chao (author), Xu, Ji Sheng (author), Stolle, Claudia (author), van den IJssel, J.A.A. (author), Yin, Fan (author), Kervalishvili, Guram N. (author), Zangerl, Franz (author)

Transient signal loss of the global positioning system (GPS) has been frequently observed by receivers on board the European Space Agency's Swarm mission when the satellites encounter ionospheric plasma irregularities. In this study we provided the first comparison of the GPS signal amplitude degradations from receivers on board low Earth...

journal article 2020

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Description of the multi-approach gravity field models from Swarm GPS data

De Teixeira Da Encarnação, J. (author), Visser, P.N.A.M. (author), Arnold, Daniel (author), Bezdek, Ales (author), Doornbos, E.N. (author), Ellmer, Matthias (author), Guo, Junyi (author), van den IJssel, J.A.A. (author), Iorfida, E. (author)

Although the knowledge of the gravity of the Earth has improved considerably with CHAMP, GRACE, and GOCE (see appendices for a list of abbreviations) satellite missions, the geophysical community has identified the need for the continued monitoring of the time-variable component with the purpose of estimating the hydrological and...

journal article 2020

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Thermosphere densities derived from Swarm GPS observations

van den IJssel, J.A.A. (author), Doornbos, Eelco (author), Iorfida, E. (author), March, G. (author), Siemes, C. (author), Montenbruck, Oliver (author)

After the detection of many anomalies in the Swarm accelerometer data, an alternative method has been developed to determine thermospheric densities for the three-satellite mission. Using a precise orbit determination approach, non-gravitational and aerodynamic-only accelerations are estimated from the high-quality Swarm GPS data. The GPS...

journal article 2020

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Absolute and relative orbit determination for the CHAMP/GRACE constellation

Mao, X. (author), Visser, P.N.A.M. (author), van den IJssel, J.A.A. (author)

Precise orbit determination was investigated for a satellite constellation comprised of two different missions, the CHAllenging Minisatellite Payload (CHAMP) satellite and the Gravity Recovery And Climate Experiment (GRACE) twin satellites. The orbital planes of these two missions aligned closely during March to May 2005, allowing precise...

journal article 2019

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High-dynamic baseline determination for the Swarm constellation

Mao, X. (author), Visser, P.N.A.M. (author), van den IJssel, J.A.A. (author)

Baseline determination for the European Space Agency Swarm magnetic field mission is investigated. Swarm consists of three identical satellites -A, -B and -C. The Swarm-A and -C form a pendulum formation whose baseline length varies between about 30 and 180 km. Swarm-B flies in a higher orbit, causing its orbital plane to slowly rotate with...

journal article 2019

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The impact of GPS receiver modifications and ionospheric activity on Swarm baseline determination

Mao, X. (author), Visser, P.N.A.M. (author), van den IJssel, J.A.A. (author)

The European Space Agency (ESA) Swarm mission is a satellite constellation launched on 22 November 2013 aiming at observing the Earth geomagnetic field and its temporal variations. The three identical satellites are equipped with high-precision dual-frequency Global Positioning System (GPS) receivers, which make the constellation an ideal...

journal article 2018

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Update on thermospheric density products from satellite observations

March, G. (author), Visser, T. (author), Doornbos, E.N. (author), Iorfida, E. (author), van den IJssel, J.A.A. (author), Visser, P.N.A.M. (author)

poster 2018