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The generation of charge during hypervelocity impacts of microparticles provides one of the most sensitive methods for the detection and characterisation of dust particles in space. Linear time-of- flight (TOF) mass spectrometry provides an opportunity for investigating the thermodynamical properties of an impact ionisation plasma, e.g. the velocity distribution of the ions. The dependence of the plasma properties on the impact parameters were studied at the Heidelberg dust accelerator laboratory using impacts speed from 1 to 90 kms-1 and particle sizes form 30nm to 4μm. The results imply that the defining parameter of impact ionisation is either the impact velocity or the energy density and not the total impact energy.

In‐situ cosmic dust instruments and measurements played a critical role in the emergence of the field of dusty plasmas. The major breakthroughs included the discovery of β‐meteoroids, interstellar dust particles within the solar system, Jovian stream particles, and the detection and analysis of Enceladus's plumes. The science goals of cosmic dust research require the measurements of the charge, the spatial, size and velocity distributions, and the chemical and isotopic compositions of individual dust particles. In‐situ dust instrument technology has improved significantly in the last decade. Modern dust instruments with high sensitivity can detect submicron‐sized particles even at low impact velocities. Innovative ion optics methods deliver high mass resolution, m/dm>100, for chemical and isotopic analysis. The accurate trajectory measurement of cosmic dust is made possible even for submicron‐sized grains using the Dust Trajectory Sensor (DTS). This article is a brief review of the current capabilities of...

The stream particles are nanometer‐size dust particles ejected from the jovian and the saturnian systems with velocities greater than 100 kms−1. Due to their small size, stream particles are more sensitive to the electromagnetic force than to gravity. It has been shown by the simulations that the stream—particle dynamics in interplanetary space should be dominated by the interplanetary magnetic field (IMF) [15]. Based on the measurements by the dust detector on board the Cassini spacecraft, we found that the detection patterns of the stream particles are well correlated with the IMF structures. As the spacecraft crosses the compression regions of the Co—rotation Interaction Regions (CIRs), not only the directionality of the impacts changes with the field direction, but also the impact signal and rate vary with an increase of field strength. By understanding the interaction of stream particles and the solar wind, the data provide important insight to the formation environments of the stream particles and i...

We present in this paper new interstellar dust data obtained in the inner solar system by the dust instruments on‐board the Cassini, Galileo and Helios spacecraft. While the Ulysses dust instrument provided an in‐situ monitoring of the interstellar dust stream at high ecliptic latitude between 3 AU and 5 AU, the new data cover an heliocentric distance range between 0.3 AU and 3 AU in the ecliptic plane. We show therefore in this paper the deep penetration of interstellar dust inside the Solar System. Furthermore, the data provide evidence of the interstellar dust stream alteration in the inner solar system, caused by radiation pressure forces and gravitation focusing.