All Stories

  1. Solar Orbiter encounters an unusually high Mach number interplanetary shock

    Article • EAS Publications Series, May 2026, EDP Sciences

    Heli Hietala

  2. Compressive Structures in the Foreshock of Collisionless Shocks

    Article • The Astrophysical Journal Letters, March 2026, American Astronomical Society

    Heli Hietala, Savvas Raptis

  3. Energetic Protons at Solar Orbiter Shocks: Efficiency, Variability, and Energetic Particle Pressure-Dominated Events

    Article • March 2026, Copernicus GmbH

    Heli Hietala

  4. Ion Plasma Stability Downstream of Collisionless Shocks Across the Mach Number Regimes

    Article • March 2026, Copernicus GmbH

    Heli Hietala

  5. Magnetic overshoots at heliospheric shocks: parameter studies

    Article • March 2026, Copernicus GmbH

    Heli Hietala

  6. Statistical Maps of Foreshock Waves Utilising 23 Years of Cluster Data

    Article • March 2026, Copernicus GmbH

    Heli Hietala

  7. Comparison of Particle Acceleration at Planetary Bow Shocks and Interplanetary Shocks

    Article • March 2026, Copernicus GmbH

    Heli Hietala

  8. Magnetic reconnection and high-speed jets downstream of a parallel shock: Full PIC simulation

    Article • March 2026, Copernicus GmbH

    Heli Hietala

  9. Establishing a European Heliophysics Community (EHC)

    Article • Annales Geophysicae, December 2025, Copernicus GmbH

    Heli Hietala

  10. Magnetic Reconnection in the Heliospheric Current Sheet Embedded in an Interplanetary Coronal Mass Ejection Sheath

    Article • The Astrophysical Journal Letters, November 2025, American Astronomical Society

    Heli Hietala

  11. Fermi Acceleration of Electrons at Earth's Bow Shock Due To Current Sheet Interaction

    Article • Journal of Geophysical Research Space Physics, August 2025, American Geophysical Union (AGU)

    Heli Hietala, Savvas Raptis

  12. Establishing a European Heliophysics Community (EHC)

    Article • August 2025, Copernicus GmbH

    Heli Hietala

  13. Investigation of the Ultralow Frequency (ULF) foreshock boundary at Mercury

    Article • May 2025, Copernicus GmbH

    Heli Hietala

  14. Statistical Study of Magnetic Overshoots at Collisionless Shocks

    Article • Journal of Geophysical Research Space Physics, May 2025, American Geophysical Union (AGU)

    Heli Hietala

  15. Electron Acceleration Comparison of the Venusian and Terrestrial Bow Shocks

    Article • March 2025, Copernicus GmbH

    Heli Hietala

  16. Microstructure at a fully formed Forward-Reverse Shock pair due to the interaction between two Coronal Mass Ejections observed at 0.5 AU.

    Article • March 2025, Copernicus GmbH

    Heli Hietala

  17. Turbulence Surrounding Magnetosheath Jets: Are Pressure Enhancement Stirring the Magnetosheath?

    Article • March 2025, Copernicus GmbH

    Heli Hietala

  18. Investigating jets downstream of interplanetary shocks

    Article • March 2025, Copernicus GmbH

    Heli Hietala

  19. An Overview of Solar Orbiter Observations of Interplanetary Shocks in Solar Cycle 25

    Article • The Astrophysical Journal Supplement Series, February 2025, American Astronomical Society

    Heli Hietala

  20. Downstream jets at interplanetary shocks: first observations and comparison with the magnetosheath

    Article • January 2025, Copernicus GmbH

    Heli Hietala

  21. Interplanetary shocks and particle energisation in the inner heliosphere

    Article • January 2025, Copernicus GmbH

    Heli Hietala

  22. Jets Downstream of Collisionless Shocks: Recent Discoveries and Challenges

    Article • Space Science Reviews, December 2024, Springer Science + Business Media

    Heli Hietala

  23. Observation of a Fully-formed Forward–Reverse Shock Pair due to the Interaction between Two Coronal Mass Ejections at 0.5 au

    Article • The Astrophysical Journal Letters, August 2024, American Astronomical Society

    Heli Hietala

  24. Candidates for downstream jets at interplanetary shocks

    Article • Monthly Notices of the Royal Astronomical Society, May 2024, Oxford University Press (OUP)

    Heli Hietala

  25. Properties of an Interplanetary Shock Observed at 0.07 and 0.7 au by Parker Solar Probe and Solar Orbiter

    Article • The Astrophysical Journal, February 2024, American Astronomical Society

    Heli Hietala

  26. Irregular Proton Injection to High Energies at Interplanetary Shocks

    Article • The Astrophysical Journal Letters, November 2023, American Astronomical Society

    Heli Hietala

  27. Self-consistent modeling of the energetic storm particle event of November 10, 2012

    Article • EAS Publications Series, November 2023, EDP Sciences

    Heli Hietala

  28. Solar Wind Parameters Influencing Magnetosheath Jet Formation: Low and High IMF Cone Angle Regimes

    Article • Journal of Geophysical Research Space Physics, October 2023, American Geophysical Union (AGU)

    Heli Hietala

  29. Shocklets and Short Large Amplitude Magnetic Structures (SLAMS) in the High Mach Foreshock of Venus

    Article • Geophysical Research Letters, September 2023, American Geophysical Union (AGU)

    Heli Hietala

  30. Annual Variations in the Near-Earth Solar Wind

    Article • Solar Physics, September 2023, Springer Science + Business Media

    Heli Hietala

  31. Three-dimensional modelling of the shock–turbulence interaction

    Article • Monthly Notices of the Royal Astronomical Society, August 2023, Oxford University Press (OUP)

    Heli Hietala

  32. Magnetosheath Jets Over Solar Cycle 24: An Empirical Model

    Article • Journal of Geophysical Research Space Physics, August 2023, American Geophysical Union (AGU)

    Heli Hietala

  33. Candidates for downstream jets at interplanetary shocks

    Article • May 2023, Copernicus GmbH

    Heli Hietala

  34. Jets downstream of the Earth’s bow shock

    Article • May 2023, Copernicus GmbH

    Heli Hietala

  35. Morphology and evolution of foreshock structures in a high-Mach number hybrid-Vlasov simulation of Earth's magnetosphere

    Article • May 2023, Copernicus GmbH

    Heli Hietala

  36. Observations of energetic particles at interplanetary shocks with Solar Orbiter

    Article • May 2023, Copernicus GmbH

    Heli Hietala

  37. On the scale sizes of magnetic holes

    Article • May 2023, Copernicus GmbH

    Heli Hietala

  38. Solar wind parameters influencing magnetosheath jet formation: low and high IMF cone angle regimes

    Article • May 2023, Copernicus GmbH

    Heli Hietala

  39. Transmission of turbulent structures and energetic particles dynamics in the interaction between collisionless shocks and plasma turbulence.

    Article • May 2023, Copernicus GmbH

    Heli Hietala

  40. Waves upstream of interplanetary shocks

    Article • May 2023, Copernicus GmbH

    Heli Hietala

  41. Multi-spacecraft observations of shocklets at an interplanetary shock

    Article • Monthly Notices of the Royal Astronomical Society, January 2023, Oxford University Press (OUP)

    Heli Hietala

  42. Investigating the role of magnetosheath high‐speed jets in triggering dayside ground magnetic ultra‐low frequency waves

    Article • Geophysical Research Letters, November 2022, American Geophysical Union (AGU)

    Heli Hietala

  43. Single-spacecraft techniques for shock parameters estimation: A systematic approach

    Article • Frontiers in Astronomy and Space Sciences, October 2022, Frontiers

    Heli Hietala

  44. Monte Carlo Simulations of Electron Acceleration at Bow Waves Driven by Fast Jets in the Earth’s Magnetosheath

    Article • The Astrophysical Journal, August 2022, American Astronomical Society

    Heli Hietala

  45. On the Transmission of Turbulent Structures across the Earth’s Bow Shock

    Article • The Astrophysical Journal, July 2022, American Astronomical Society

    Heli Hietala

  46. Magnetosheath jet occurrence rate in relation to CMEs and SIRs

    Article • April 2022, Wiley

    Heli Hietala

  47. Magnetosheath Jet Occurrence Rate in Relation to CMEs and SIRs

    Article • Journal of Geophysical Research Space Physics, April 2022, American Geophysical Union (AGU)

    Heli Hietala

  48. Magnetosheath jet occurrence in solar wind parameter space

    Article • March 2022, Copernicus GmbH

    Heli Hietala

  49. Magnetosheath jets at the magnetopause: reconnection onset conditions

    Article • March 2022, Copernicus GmbH

    Heli Hietala

  50. Self-consistent Monte-Carlo modeling of the November 10, 2012 energetic storm particle event

    Article • March 2022, Copernicus GmbH

    Heli Hietala

  51. Magnetosheath jet occurrence rate in relation to CMEs and SIRs

    Article • November 2021, Wiley

    Heli Hietala

  52. Magnetic Field in Magnetosheath Jets: A Statistical Study of BZ Near the Magnetopause

    Article • Journal of Geophysical Research Space Physics, September 2021, American Geophysical Union (AGU)

    Heli Hietala

  53. Solar Wind Control of Magnetosheath Jet Formation and Propagation to the Magnetopause

    Article • Journal of Geophysical Research Space Physics, September 2021, American Geophysical Union (AGU)

    Heli Hietala

  54. Interplanetary Shock‐Induced Magnetopause Motion: Comparison Between Theory and Global Magnetohydrodynamic Simulations

    Article • Geophysical Research Letters, August 2021, American Geophysical Union (AGU)

    Heli Hietala

  55. Ion distribution functions in magnetotail reconnection: global hybrid-Vlasov simulation results

    Article • Annales Geophysicae, July 2021, Copernicus GmbH

    Heli Hietala

  56. Solar Wind Control of Magnetosheath Jet Formation and Propagation to the Magnetopause

    Article • June 2021, Wiley

    Heli Hietala

  57. Enhanced proton parallel temperature inside patches of switchbacks in the inner heliosphere

    Article • EAS Publications Series, June 2021, EDP Sciences

    Dr Lloyd D. Woodham, Heli Hietala

  58. Direct Multipoint Observations Capturing the Reformation of a Supercritical Fast Magnetosonic Shock

    Article • The Astrophysical Journal Letters, April 2021, American Astronomical Society

    Heli Hietala

  59. Electron Trapping in Magnetic Mirror Structures at the Edge of Magnetopause Flux Ropes

    Article • Journal of Geophysical Research Space Physics, April 2021, American Geophysical Union (AGU)

    Heli Hietala

  60. HYPERS simulations of solar wind interactions with the Earth's magnetosphere and the Moon

    Article • Journal of Atmospheric and Solar-Terrestrial Physics, April 2021, Elsevier

    Heli Hietala

  61. Interplanetary Shock-driven Magnetopause Compressions in Gorgon Global-MHD Simulations

    Article • March 2021, Copernicus GmbH

    Heli Hietala

  62. Jet-driven bow waves as electron accelerators in the magnetosheath: Monte Carlo simulations

    Article • March 2021, Copernicus GmbH

    Heli Hietala

  63. Ion distribution functions in magnetotail reconnection: Global hybrid-Vlasov simulation results

    Article • February 2021, Copernicus GmbH

    Heli Hietala

  64. Magnetohydrodynamic With Embedded Particle‐In‐Cell Simulation of the Geospace Environment Modeling Dayside Kinetic Processes Challenge Event

    Article • Earth and Space Science, October 2020, American Geophysical Union (AGU)

    Heli Hietala

  65. Scale Sizes of Magnetosheath Jets

    Article • Journal of Geophysical Research Space Physics, September 2020, American Geophysical Union (AGU)

    Heli Hietala

  66. Electron Acceleration by Magnetosheath Jet‐Driven Bow Waves

    Article • Journal of Geophysical Research Space Physics, July 2020, American Geophysical Union (AGU)

    Heli Hietala

  67. Statistical Study of Magnetosheath Jet‐Driven Bow Waves

    Article • Journal of Geophysical Research Space Physics, July 2020, American Geophysical Union (AGU)

    Heli Hietala

  68. Calibration of RADMON radiation monitor onboard Aalto-1 CubeSat

    Article • Advances in Space Research, July 2020, Elsevier

    Heli Hietala

  69. Radiation monitor RADMON aboard Aalto-1 CubeSat: First results

    Article • Advances in Space Research, July 2020, Elsevier

    Heli Hietala

  70. Compiling Magnetosheath Statistical Data Sets Under Specific Solar Wind Conditions: Lessons Learnt From the Dayside Kinetic Southward IMF GEM Challenge

    Article • Earth and Space Science, May 2020, American Geophysical Union (AGU)

    Heli Hietala

  71. Magnetic field within magnetosheath jets during northward and southward interplanetary magnetic field conditions

    Article • March 2020, Copernicus GmbH

    Heli Hietala

  72. Magnetic mirror structures associated with magnetopause flux ropes investigated with Mangnetospheric Multiscale misson (MMS)

    Article • March 2020, Copernicus GmbH

    Heli Hietala

  73. On the scale sizes of magnetosheath jets

    Article • March 2020, Copernicus GmbH

    Heli Hietala

  74. Particle acceleration by transient structures around Earth’s bow shock

    Article • March 2020, Copernicus GmbH

    Heli Hietala

  75. On the alignment of velocity and magnetic fields within magnetosheath jets

    Article • Annales Geophysicae, March 2020, Copernicus GmbH

    Heli Hietala

  76. The Challenges and Rewards of Running a Geospace Environment Modeling Challenge

    Article • Journal of Geophysical Research Space Physics, March 2020, American Geophysical Union (AGU)

    Heli Hietala

  77. Characteristics of the Flank Magnetopause: MMS Results

    Article • Journal of Geophysical Research Space Physics, March 2020, American Geophysical Union (AGU)

    Heli Hietala

  78. Jets in the magnetosheath: IMF control of where they occur

    Article • Annales Geophysicae, August 2019, Copernicus GmbH

    Heli Hietala

  79. THEMIS Observations of Particle Acceleration by a Magnetosheath Jet‐Driven Bow Wave

    Article • Geophysical Research Letters, July 2019, American Geophysical Union (AGU)

    Heli Hietala

  80. On the alignment of velocity and magnetic fields within magnetosheath jets

    Article • Annales Geophysicae Discussions, July 2019, Copernicus GmbH

    Heli Hietala

  81. FORESAIL‐1 CubeSat Mission to Measure Radiation Belt Losses and Demonstrate Deorbiting

    Article • Journal of Geophysical Research Space Physics, July 2019, American Geophysical Union (AGU)

    Heli Hietala

  82. Jets in the Magnetosheath: IMF Control of Where They Occur

    Article • Annales Geophysicae Discussions, May 2019, Copernicus GmbH

    Heli Hietala

  83. Outer Van Allen Radiation Belt Response to Interacting Interplanetary Coronal Mass Ejections

    Article • Journal of Geophysical Research Space Physics, March 2019, American Geophysical Union (AGU)

    Heli Hietala

  84. Direct observations of a surface eigenmode of the dayside magnetopause

    Article • Nature Communications, February 2019, Springer Science + Business Media

    Heli Hietala

  85. The response of Earth's electron radiation belts to geomagnetic storms: Statistics from the Van Allen Probes era including effects from different storm drivers

    Article • Journal of Geophysical Research Space Physics, January 2019, American Geophysical Union (AGU)

    Heli Hietala

  86. Magnetosheath jet properties and evolution as determined by a global hybrid-Vlasov simulation

    Article • Annales Geophysicae, September 2018, Copernicus GmbH

    Heli Hietala

  87. Dayside Magnetospheric and Ionospheric Responses to a Foreshock Transient on 25 June 2008: 2.2-D Evolution Based on Dayside Auroral Imaging

    Article • Journal of Geophysical Research Space Physics, August 2018, American Geophysical Union (AGU)

    Heli Hietala, Boyi Wang

  88. Impacts of Magnetosheath High-Speed Jets on the Magnetosphere and Ionosphere Measured by Optical Imaging and Satellite Observations

    Article • Journal of Geophysical Research Space Physics, June 2018, American Geophysical Union (AGU)

    Heli Hietala, Boyi Wang

  89. Jets Downstream of Collisionless Shocks

    Article • Space Science Reviews, June 2018, Springer Science + Business Media

    Heli Hietala

  90. Plasma flow patterns in and around magnetosheath jets

    Article • Annales Geophysicae, May 2018, Copernicus GmbH

    Heli Hietala

  91. Investigating the anatomy of magnetosheath jets – MMS observations

    Article • Annales Geophysicae, April 2018, Copernicus GmbH

    Heli Hietala

  92. Magnetosheath jet properties and evolution as determined by a global hybrid-Vlasov simulation

    Article • Annales Geophysicae Discussions, March 2018, Copernicus GmbH

    Heli Hietala

  93. Magnetosheath jet properties and evolution as determined by a global hybrid-Vlasov simulation

    Article • March 2018, Copernicus GmbH

    Heli Hietala

  94. In situ observations of a magnetosheath high-speed jet triggering magnetopause reconnection

    Article • Geophysical Research Letters, February 2018, Wiley

    Heli Hietala

  95. Magnetotail fast flow occurrence rate and dawn-dusk asymmetry at X G S M ∼ -60 R ...

    Article • Journal of Geophysical Research Space Physics, January 2018, Wiley

    Heli Hietala

  96. Global MHD simulations of the Earth's bow shock shape and motion under variable solar wind conditions

    Article • Journal of Geophysical Research Space Physics, December 2017, Wiley

    Heli Hietala

  97. Tail reconnection in the global magnetospheric context: Vlasiator first results

    Article • Annales Geophysicae, November 2017, Copernicus GmbH

    Heli Hietala

  98. Different Types of Ion Populations Upstream of the 2013 October 8 Interplanetary Shock

    Article • The Astrophysical Journal Letters, November 2017, American Astronomical Society

    Heli Hietala

  99. Magnetosheath High-Speed Jets: Internal Structure and Interaction With Ambient Plasma

    Article • Journal of Geophysical Research Space Physics, October 2017, Wiley

    Heli Hietala, Anonymous User

  100. Fermi acceleration of electrons inside foreshock transient cores

    Article • Journal of Geophysical Research Space Physics, September 2017, Wiley

    Heli Hietala

  101. Energetic ion leakage from foreshock transient cores

    Article • Journal of Geophysical Research Space Physics, July 2017, American Geophysical Union (AGU)

    Heli Hietala

  102. Statistical study of particle acceleration in the core of foreshock transients

    Article • Journal of Geophysical Research Space Physics, July 2017, American Geophysical Union (AGU)

    Heli Hietala

  103. Statistical properties of solar wind reconnection exhausts

    Article • Journal of Geophysical Research Space Physics, June 2017, American Geophysical Union (AGU)

    Heli Hietala

  104. Growth rate measurement of ULF waves in the ion foreshock

    Article • Geophysical Research Letters, March 2017, American Geophysical Union (AGU)

    Heli Hietala

  105. Reconnection rates and X line motion at the magnetopause: Global 2D‐3V hybrid‐Vlasov simulation results

    Article • Journal of Geophysical Research Space Physics, March 2017, American Geophysical Union (AGU)

    Heli Hietala

  106. Ion density and temperature profiles along ( X GSM ) and across ( Z GSM ) the magnetotail as observed by THEMIS, Geotail, and ARTEMIS

    Article • Journal of Geophysical Research Space Physics, February 2017, American Geophysical Union (AGU)

    Heli Hietala

  107. Observational properties of dayside throat aurora and implications on the possible generation mechanisms

    Article • Journal of Geophysical Research Space Physics, February 2017, American Geophysical Union (AGU)

    Professor De-Sheng Han, Heli Hietala

  108. Ion dynamics in magnetotail reconnection in the presence of density asymmetry

    Article • Journal of Geophysical Research Space Physics, February 2017, American Geophysical Union (AGU)

    Heli Hietala

  109. Evidence for transient, local ion foreshocks caused by dayside magnetopause reconnection

    Article • Annales Geophysicae, November 2016, Copernicus GmbH

    Heli Hietala

  110. Observations of Hall Reconnection Physics Far Downstream of the X Line

    Article • Physical Review Letters, October 2016, American Physical Society (APS)

    Heli Hietala

  111. Strong current sheet at a magnetosheath jet: Kinetic structure and electron acceleration

    Article • Journal of Geophysical Research Space Physics, October 2016, American Geophysical Union (AGU)

    Heli Hietala

  112. Observations of a new foreshock region upstream of a foreshock bubble's shock

    Article • Geophysical Research Letters, May 2016, American Geophysical Union (AGU)

    Heli Hietala

  113. Geoeffective jets impacting the magnetopause are very common

    Article • Journal of Geophysical Research Space Physics, April 2016, American Geophysical Union (AGU)

    Heli Hietala

  114. Development of bifurcated current sheets in solar wind reconnection exhausts

    Article • Geophysical Research Letters, December 2015, American Geophysical Union (AGU)

    Heli Hietala

  115. The effects of geomagnetic storms on electrons in Earth's radiation belts

    Article • Geophysical Research Letters, November 2015, American Geophysical Union (AGU)

    Heli Hietala

  116. ULF foreshock under radial IMF: THEMIS observations and global kinetic simulation Vlasiator results compared

    Article • Journal of Geophysical Research Space Physics, October 2015, American Geophysical Union (AGU)

    Heli Hietala

  117. Ion temperature anisotropy across a magnetotail reconnection jet

    Article • Geophysical Research Letters, September 2015, American Geophysical Union (AGU)

    Heli Hietala

  118. Unraveling the drivers of the storm time radiation belt response

    Article • Geophysical Research Letters, May 2015, American Geophysical Union (AGU)

    Heli Hietala, Dr Geoffrey D Reeves

  119. Detection of small-scale folds at a solar wind reconnection exhaust

    Article • Journal of Geophysical Research Space Physics, January 2015, American Geophysical Union (AGU)

    Heli Hietala

  120. Ion reflection and acceleration near magnetotail dipolarization fronts associated with magnetic reconnection

    Article • Journal of Geophysical Research Space Physics, January 2015, American Geophysical Union (AGU)

    Heli Hietala

  121. What Controls the Structure and Dynamics of Earth’s Magnetosphere?

    Article • Space Science Reviews, June 2014, Springer Science + Business Media

    Heli Hietala

  122. Depleting effects of ICME-driven sheath regions on the outer electron radiation belt

    Article • Geophysical Research Letters, April 2014, American Geophysical Union (AGU)

    Heli Hietala

  123. Sequentially released tilted flux ropes in the Earth's magnetotail

    Article • Plasma Physics and Controlled Fusion, April 2014, Institute of Physics Publishing

    Heli Hietala

  124. On the generation of magnetosheath high-speed jets by bow shock ripples

    Article • Journal of Geophysical Research Space Physics, November 2013, American Geophysical Union (AGU)

    Heli Hietala

  125. Anti-sunward high-speed jets in the subsolar magnetosheath

    Article • Annales Geophysicae, October 2013, Copernicus GmbH

    Heli Hietala

  126. Injection of thermal and suprathermal seed particles into coronal shocks of varying obliquity

    Article • EAS Publications Series, October 2013, EDP Sciences

    Heli Hietala

  127. Magnetic field and dynamic pressure ULF fluctuations in coronal-mass-ejection-driven sheath regions

    Article • Annales Geophysicae, September 2013, Copernicus GmbH

    Heli Hietala

  128. A comparison of bow shock models with Cluster observations during low Alfvén Mach number magnetic clouds

    Article • Annales Geophysicae, June 2013, Copernicus GmbH

    Heli Hietala

  129. Analysis of the substructure within a complex magnetic cloud on 3–4 September 2008

    Article • Annales Geophysicae, March 2013, Copernicus GmbH

    Heli Hietala

  130. PARTICLE ACCELERATION IN SHOCK–SHOCK INTERACTION: MODEL TO DATA COMPARISON

    Article • The Astrophysical Journal Letters, May 2012, Institute of Physics Publishing

    Heli Hietala

  131. Supermagnetosonic subsolar magnetosheath jets and their effects: from the solar wind to the ionospheric convection

    Article • Annales Geophysicae, January 2012, Copernicus GmbH

    Heli Hietala

  132. In situ observations of particle acceleration in shock-shock interaction

    Article • Journal of Geophysical Research Atmospheres, October 2011, American Geophysical Union (AGU)

    Heli Hietala

  133. Supermagnetosonic Jets behind a Collisionless Quasiparallel Shock

    Article • Physical Review Letters, December 2009, American Physical Society (APS)

    Heli Hietala

  134. Damage in impact fragmentation

    Article • International Journal of Fracture, September 2009, Springer Science + Business Media

    Heli Hietala

  135. Damage in impact fragmentation

    Article • January 2009, Springer Science + Business Media

    Heli Hietala