Cyril Simon Wedlund

Academic interests

My science interests range from aeronomy (auroral emissions, ionospheric plasma) to planetary space sciences (comets, Mars/Venus). 

I am currently involved in the ESA Rosetta mission to comet 67P/C-G with emphasis on the interpretation of ion and plasma measurements from the RPC suite of instruments by use of global hybrid simulations. My interests range from electron and proton precipitation of solar origin in the atmospheres of the Earth, Mars and Venus to the physico-chemical processes at the origin of airglow and aurora in the solar system, using space-born (Mars Express, Rosetta, Cluster, DMSP) and ground-based (EISCAT, ALIS) instrumentation. In order to analyse, understand and interpret these complex datasets, I develop and use numerical models describing in 1-D or in 3-D the space environment of planets and comets.


I hold a PhD in Astrophysics from the University Joseph Fourier of Grenoble, France (2006).

Keywords: Comets, Earth, Mars, Simulations: Hybrid/PIC model development, Kinetic transport of electrons and protons, Ionosphere-Magnetosphere coupling, Optical tomography of the aurora, solar wind mass loading, data analysis and interpretation, Rosetta, Mars Express, EISCAT, ALIS.

Positions held

  • Research Associate, Aalto University, Department of Radio Science and Electrical Engineering, Espoo, Finland (2014-2015)
  • Researcher, Finnish Meteorological Institute (FMI), Helsinki, Finland (2013)
  • Researcher, Belgian Institute for Space Aeronomy (BIRA-IASB), Brussels, Belgium (2008-2012)
  • Research fellow, European Space Agency ESA, Noordwijk, Netherlands (2006-2008)


Tags: Comets, Mars, Earth, Modelling and simulation, Ionospheres, Magnetospheres, Aurora


  • Simon Wedlund, Cyril; Bodewits, Dennis; Alho, Markku; Hoekstra, Ronnie; Behar, Etienne; Gronoff, Guillaume; Gunell, Herbert; Nilsson, Hans; Kallio, Esa & Beth, Arnaud (2019). Solar wind charge exchange in cometary atmospheres - I. Charge-changing and ionization cross sections for He and H particles in H2O. Astronomy and Astrophysics.  ISSN 0004-6361.  630, s 1- 22 . doi: 10.1051/0004-6361/201834848
  • Egeland, Alv & Simon Wedlund, Cyril (2018). Birkeland's Electromagnetic Cannon. IEEE Transactions on Plasma Science.  ISSN 0093-3813.  46(6), s 2154- 2161 . doi: 10.1109/TPS.2018.2834980
  • Madsen, Birgitte; Simon Wedlund, Cyril; Eriksson, A.; Goetz, C.; Karlsson, T.; Gunell, H.; Spicher, Andres; Henri, P; Vallieres, X & Miloch, Wojciech Jacek (2018). Extremely Low-Frequency Waves Inside the Diamagnetic Cavity of Comet 67P/Churyumov-Gerasimenko. Geophysical Research Letters.  ISSN 0094-8276.  45(9), s 3854- 3864 . doi: 10.1029/2017GL076415 Full text in Research Archive.
  • Bougher, Stephen W.; Brain, David A.; Fox, Jane L.; Gonzalez-Galindo, Francisco; Simon Wedlund, Cyril & Withers, Paul G. (2017). Upper Neutral Atmosphere and Ionosphere, In Richard W. Zurek (ed.),  The Atmosphere and Climate of Mars.  Cambridge University Press.  ISBN 9781107016187.  14.  s 433 - 463
  • Eriksson, AI; Engelhardt, IAD; Andre, M; Boström, R; Edberg, NJT; Johansson, F. L.; Odelstad, E; Vigren, E.; Wahlund, JE; Henri, P; Lebreton, JP; Miloch, Wojciech Jacek; Paulsson, Joakim John Paul; Simon Wedlund, Cyril; Yang, Lei; Karlsson, T; Jarvinen, R; Broiles, T.; Mandt, K.; Carr, C. M.; Galand, M; Nilsson, H & Norberg, C (2017). Cold and warm electrons at comet 67P/Churyumov-Gerasimenko. Astronomy and Astrophysics.  ISSN 0004-6361.  605 . doi: 10.1051/0004-6361/201630159
  • Gunell, H.; Goetz, C.; Eriksson, A; Nilsson, H; Simon Wedlund, Cyril; Henri, P; Maggiolo, R.; Hamrin, M.; De Keyser, J; Rubin, M; Stenberg Wieser, Gabriella; Cessateur, G; Dhooghe, F & Gibbons, Alison (2017). Plasma waves confined to the diamagnetic cavity of comet 67P/Churyumov–Gerasimenko. Monthly notices of the Royal Astronomical Society.  ISSN 0035-8711.  469, s S84- S92
  • Gunell, H.; Nilsson, H; Hamrin, M; Eriksson, A; Odelstad, E; Maggiolo, R.; Henri, P; Vallieres, X; Altwegg, K; Tzou, C -Y; Rubin, M; Glassmeier, K. H.; Wieser, G Stenberg; Simon Wedlund, Cyril; De Keyser, J.; Dhooghe, F; Cessateur, G & Gibbons, Anne Marthe Nilsen (2017). Ion acoustic waves at comet 67P/Churyumov-Gerasimenko: Observations and computations. Astronomy and Astrophysics.  ISSN 0004-6361.  600 . doi: 10.1051/0004-6361/201629801
  • Johansson, Fredrik; Odelstad, E; Paulsson, Joakim John Paul; Harang, Sigve Smedsrud; Eriksson, AI; Mannel, Thurid; Vigren, E.; Edberg, NJT; Miloch, Wojciech Jacek; Simon Wedlund, Cyril; Thiemann, E; Eparvier, Francis G. & Anderson, L (2017). Rosetta photoelectron emission and solar ultraviolet flux at comet 67P. Monthly notices of the Royal Astronomical Society.  ISSN 0035-8711.  469, s S626- S635 . doi: 10.1093/mnras/stx2369
  • Nilsson, Hans; Stenberg Wieser, Gabriella; Behar, Etienne; Gunell, Herbert; Wieser, Martin; Galand, M; Simon Wedlund, Cyril; Alho, Markku; Goetz, C.; Yamauchi, Masanori; Henri, Pierre; Odelstad, Elias & Vigren, E. (2017). Evolution of the ion environment of comet 67P during the Rosetta mission as seen by RPC-ICA. Monthly notices of the Royal Astronomical Society.  ISSN 0035-8711.  469, s S252- S261 . doi: 10.1093/mnras/stx1491
  • Simon Wedlund, Cyril; Alho, M.; Gronoff, G.; Kallio, E.; Gunell, H.; Nilsson, H.; Lindkvist, J.; Behar, E.; Stenberg Wieser, G. & Miloch, Wojciech Jacek (2017). Hybrid modelling of cometary plasma environments: I. Impact of photoionisation, charge exchange, and electron ionisation on bow shock and cometopause at 67P/Churyumov-Gerasimenko. Astronomy and Astrophysics.  ISSN 0004-6361.  604 . doi: 10.1051/0004-6361/201730514
  • Stenberg Wieser, Gabriella; Odelstad, Elias; Wieser, Martin; Nilsson, Hans; Goetz, C.; Karlsson, Tomas; André, Mats; Kalla, Leif; Eriksson, Anders; Nicolaou, Georgios; Simon Wedlund, Cyril; Richter, Ingo & Gunell, Herbert (2017). Investigating short-time-scale variations in cometary ions around comet 67P. Monthly notices of the Royal Astronomical Society.  ISSN 0035-8711.  469, s S522- S534 . doi: 10.1093/mnras/stx2133
  • Yang, Lei; Paulsson, Joakim John Paul; Simon Wedlund, Cyril; Odelstad, Elias; Edberg, Niklas; Koenders, C.; Eriksson, Anders & Miloch, Wojciech Jacek (2016). Observations of high-plasma density region in the inner coma of 67P/Churyumov–Gerasimenko during early activity. Monthly notices of the Royal Astronomical Society.  ISSN 0035-8711.  462, s S33- S44 . doi: 10.1093/mnras/stw2046

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  • Héritier, Kevin L.; Altwegg, Kathrin; Berthelier, Jean-Jacques; Beth, Arnaud; Carr, Cristopher M.; De Keyser, Johan; Eriksson, Anders I.E.; Fuselier, Stephen A.; Galand, Marina; Gombosi, Tamás I.; Henri, Pierre; Johansson, Fredrik L.; Nilsson, Hans Erik; Rubin, Martin; Simon Wedlund, Cyril; Taylor, Matthew G.G.T. & Vigren, Erik (2018). On the origin of molecular oxygen in cometary comae. Nature Communications.  ISSN 2041-1723.  9:2580(1), s 1- 4 . doi: 10.1038/s41467-018-04972-5
  • Miloch, Wojciech Jacek; Yang, Lei; Paulsson, Joakim John Paul; Simon Wedlund, Cyril; Odelstad, Elias; Edberg, Niklas; Koenders, C. & Eriksson, A. (2016). Early Evolution of Comet 67P Studied with the RPC-LAP onboard Rosetta.

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Published Jan. 14, 2016 3:51 PM - Last modified July 31, 2019 2:16 PM