Thermosphere data

Free thermosphere density and wind data from the CHAMP, GRACE, GRACE-FO, GOCE, and Swarm missions.

Update on June 30, 2025: Uploaded accelerometer-derived Swarm A density data (version 01) covering the period from November 2015 to December 2016.
Update on June 17, 2025: Uploaded accelerometer-derived GRACE C density and crosswind data (version 02c) covering the period from January to April 2025.
Update on June 2, 2025: Uploaded POD-derived Swarm density data (version 02) covering April 2025.
Update on March 16, 2025: Uploaded POD-derived Swarm density data (version 02) covering the period from 2014 to 2024. We implemented a new processing method in this new version, in which the smoothing adapts to the expected signal strength. The method maximises the density signal-to-noise ratio, substantially increasing the data quality.

The data can be accessed via our anonymous FTP server thermosphere.tudelft.nl using an FTP client (e.g. FileZilla). Enter ftp://thermosphere.tudelft.nl as the host and anonymous as the username.

Data and models

All freely available on our FTP server. You might need a FTP client to open the link (user anonymous, any password is accepted).

Geometry models

High-fidelity geometry models for the CHAMP, GRACE, GOCE and Swarm satellites are freely available under Creative Commons licence CC BY-NC-SA 4.0.

Aerodynamic models

Aerodynamic models generated by the SPARTA direct simulation Monte Carlo simulator are freely available under Creative Commons licence CC BY-NC-SA 4.0.

Radiation pressure models

Radiation pressure models based on ray tracing are freely available under Creative Commons licence CC BY-NC-SA 4.0.

Density and wind data

Density and wind data for the CHAMP, GRACE, GOCE and Swarm satellites are freely available under Creative Commons licence CC BY 4.0.

TOLEOS project

The TOLEOS project enabled the reprocessing of the CHAMP and GRACE datasets as well as the processing of the GRACE-FO dataset. More information can be found here.

References

If you use the data on this webpage, please cite our publications.

Accelerometer-derived density data

N. Hładczuk, J. van den IJssel, T. Kodikara, K., C. Siemes, P. Visser (2023) GRACE-FO radiation pressure modelling for accurate density and crosswind retrieval. Advances in Space Research. https://doi.org/10.1016/j.asr.2023.12.059

C. Siemes, C. Borries, S. Bruinsma, I. Fernandez-Gomez, N. Hładczuk, J. van den IJssel, T. Kodikara, K. Vielberg, P. Visser (2023) New Thermosphere Neutral Mass Density and Crosswind Datasets from CHAMP, GRACE, and GRACE-FO. Journal of Space Weather and Space Climate. https://doi.org/10.1051/swsc/2023014

G. March, J. van den IJssel, C. Siemes, P. Visser, E. Doornbos, M. Pilinski (2021) Gas-surface interactions modelling influence on satellite aerodynamics and thermosphere density. Journal of Space Weather and Space Climate, 11: 54. https://doi.org/10.1051/swsc/2021035

C. Siemes, J. de Teixeira da Encarnação, E. N. Doornbos, J. van den IJssel, J. Kraus, R. Pereštý, L. Grunwaldt, G. Apelbaum, J. Flury and P. E. Holmdahl Olsen (2016) Swarm accelerometer data processing from raw accelerations to thermospheric neutral densities. Earth, Planets and Space, 68: 92. https://doi.org/10.1186/s40623-016-0474-5

E. N. Doornbos (2012) Thermosphere density and wind determination from satellite dynamics. Dissertation, Springer Nature, Switzerland. ISBN 978-3-642-25129-0 (free PDF version)

Satellite geometry and aerodynamic models

G. March, E. N. Doornbos and P. N. M. A. Visser (2019) High-fidelity geometry models for improving the consistency of CHAMP, GRACE, GOCE and Swarm thermospheric density data sets. Advances in Space Research 63: 213–238. https://doi.org/10.1016/j.asr.2018.07.009

G. March, E. N. Doornbos and P. N. M. A. Visser (2019) CHAMP and GOCE thermospheric wind characterization with improved gas-surface interactions modelling. Advances in Space Research 64: 1225–1242. https://doi.org/10.1016/j.asr.2019.06.023

GNSS-derived density data

J. van den IJssel, E. Doornbos, E. Iorfida, G. March, C. Siemes, O. Montenbruck (2020) Thermosphere densities derived from Swarm GPS observations. Advances in Space Research. https://doi.org/10.1016/j.asr.2020.01.004

P. Visser and J. van den IJssel J (2016) Orbit determination and estimation of non-gravitational accelerations for the GOCE reentry phase. Advances in Space Research 58: 1840–1853. https://doi.org/10.1016/j.asr.2016.07.013

The original data was obtained from the following sources

CHAMP data: GFZ's Information System and Data Center
GOCE and Swarm data: ESA's Earth Online webpage
GRACE and GRACE-FO data: NASA's Physical Oceanography Distributed Active Archive Center (PO.DAAC)

Thermosphere data

Data and models

All freely available on our FTP server. You might need a FTP client to open the link (user anonymous, any password is accepted).

Geometry models

High-fidelity geometry models for the CHAMP, GRACE, GOCE and Swarm satellites are freely available under Creative Commons licence CC BY-NC-SA 4.0.

Aerodynamic models

Aerodynamic models generated by the SPARTA direct simulation Monte Carlo simulator are freely available under Creative Commons licence CC BY-NC-SA 4.0.

Radiation pressure models

Radiation pressure models based on ray tracing are freely available under Creative Commons licence CC BY-NC-SA 4.0.

Density and wind data

Density and wind data for the CHAMP, GRACE, GOCE and Swarm satellites are freely available under Creative Commons licence CC BY 4.0.

TOLEOS project

The TOLEOS project enabled the reprocessing of the CHAMP and GRACE datasets as well as the processing of the GRACE-FO dataset. More information can be found here.

References

Team members

Christian Siemes

Jose van den IJssel

Pieter Visser

Sabin Anton

Natalia Hładczuk

Frederik Jacobs

Former team members

Eelco Doornbos

Tim Visser

Günther March

Elisabetta Iorfida

Funding sources

The generation of our models and data was supported by

ESA – European Space Agency

NWO – Dutch Research Council

Swarm DISC - Data, Innovation and Science Cluster

Address

Contact

Links

Thermosphere data

Data and models

All freely available on our FTP server. You might need a FTP client to open the link (user anonymous, any password is accepted).

Geometry modelsHigh-fidelity geometry models for the CHAMP, GRACE, GOCE and Swarm satellites are freely available under Creative Commons licence CC BY-NC-SA 4.0.

Aerodynamic modelsAerodynamic models generated by the SPARTA direct simulation Monte Carlo simulator are freely available under Creative Commons licence CC BY-NC-SA 4.0.

Radiation pressure modelsRadiation pressure models based on ray tracing are freely available under Creative Commons licence CC BY-NC-SA 4.0.

Density and wind dataDensity and wind data for the CHAMP, GRACE, GOCE and Swarm satellites are freely available under Creative Commons licence CC BY 4.0.

TOLEOS projectThe TOLEOS project enabled the reprocessing of the CHAMP and GRACE datasets as well as the processing of the GRACE-FO dataset. More information can be found here.

References

Team members

Former team members

Eelco Doornbos

Tim Visser

Günther March

Elisabetta Iorfida

Funding sources

The generation of our models and data was supported by

Address

Contact

Links

Geometry models

High-fidelity geometry models for the CHAMP, GRACE, GOCE and Swarm satellites are freely available under Creative Commons licence CC BY-NC-SA 4.0.

Aerodynamic models

Aerodynamic models generated by the SPARTA direct simulation Monte Carlo simulator are freely available under Creative Commons licence CC BY-NC-SA 4.0.

Radiation pressure models

Radiation pressure models based on ray tracing are freely available under Creative Commons licence CC BY-NC-SA 4.0.

Density and wind data

Density and wind data for the CHAMP, GRACE, GOCE and Swarm satellites are freely available under Creative Commons licence CC BY 4.0.

TOLEOS project

The TOLEOS project enabled the reprocessing of the CHAMP and GRACE datasets as well as the processing of the GRACE-FO dataset. More information can be found here.