Dust-Heliosphere Interaction

Interstellar dust in the solar system

Interstellar dust (ISD) is at the base of the formation of stars and planetary systems and plays an important role in the chemistry of the interstellar medium. To study it, we can use astronomical observations (e.g. extinction and polarisation of starlight, infrared emission of the dust), but we can also probe the interstellar dust particles from our immediate interstellar neighbourhood: the Local Interstellar Cloud (LIC). Because of the relative motion between the Sun and the LIC (ca. 26 km/s), we can investigate these interstellar dust particles within the solar system using dust detectors on spacecraft like Ulysses, Galileo, Helios and Cassini, or we can catch them at relatively low relative velocities of only a few km/s, and return them to Earth for a detailed study in the laboratory (e.g. the Stardust mission).

The trajectories of these particles that pass through the solar system are governed by several forces like solar gravitation, solar radiation pressure and Lorentz force due to the motion of the (charged) dust particles through the Interplanetary Magnetic Field (IMF). Computer simulations of ISD trajectories give insight in the variable ISD particle fluxes and directions that change throughout the solar cycle. With computer simulations, we gain insight in the ISD flow patterns in the solar system and use them as tracers for use in heliospheric modelling, investigate how much dust arrives at the Earth, the asteroid belt, Jupiter or Saturn, and we can make predictions for the fluxes to be measured by several space missions.

Simulations for the 16 years of Ulysses dust measurements indicated that the observed shift in dust flow direction in 2005/2006 may be explained by Lorentz forces, if the larger interstellar dust particles have a lower bulk density than anticipated and if a secondary filtering exists in the heliosheath boundary region [Sterken et al, 2015]. Also the Stardust mission interstellar preliminary examination resulted in strong indications that the micron-sized ISD has very low bulk densities [Westphal et al., 2012]. 

We are currently working on better understanding the heliospheric filtering in the interaction region between the heliosphere and the interstellar medium (the "heliosheath") and on completing a full dust transport model of itnerstellar dust moving through the heliosphere.

Interplanetary dust

We have supported the development of the ESA IMEX model (2013) that simulates cometary dust streams in the solar system. We also simulated and studied Io dust stream variations through the solar wind throughout time. See "other research" for the publications. 

An image of the sun from unsplash. Nothing to say about this image; it will be changed when the website is further being built.

TOPICS and REFERENCES

  • Interstellar dust in the heliosphere, processes and synergies
    • The flow of interstellar dust in the heliosphere [Sterken et al. 2012]
    • The filtering of interstellar dust in the heliosphere [Sterken et al. 2013]
    • Synergies between cosmic dust and heliospheric science for interstellar probe [Sterken et al. 2023]
    • Heliospheric modulation of the interstellar dust flow onto Earth [Strub et al., 2019]
    • Review papers: Interstellar dust in the heliosphere and astrospheres [Sterken et al. 2019, Sterken et al. 2021]
    • NASA-HQ Cross Division "Dusty Universe" talk (12 January 2023) - Youtube
  • ISD mission predictions and interpretation (see also "mission concept predictions")
    • Synergies between cosmic dust and heliospheric science for interstellar probe [Sterken et al. 2023]
    • Interstellar Probe talk (10 December 2020) - Youtube
    • Ulysses: data versus simulations [Sterken et al. 2015]
    • Ulysses: data selection, largest impacts, and heliosheath filtering [Baalmann et al., in press]
    • Cassini, Galileo, Ulysses, Helios: data and simulations [Krüger et al. 2019]
    • JUICE: predicting dust fluxes en route and near Jupiter [Sterken et al. 2012, Soja et al. 2012]
    • Stardust Interstellar Preliminary Analysis [Sterken et al. 2014, Westphal et al. 2014]
    • Cassini [Sterken et al., 2012, Altobelli et al. 2016]
    • Wind [Hervig et al. 2022, Baalmann et al. 2024]
    • New Horizons [Bernardoni et al. 2022]
  • Dust-solar wind interaction (on a local scale):
    • A solar rotation frequency in dust impacts on Wind and STEREO [Baalmann et al. 2024, Chadda et al. 2024]
  • Charging of dust (on-going, Research Assistant: T. Arnet)

See also: