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Context. In the early 1990s, contemporary interstellar dust penetrating deep into the heliosphere was identified with the in situ dust detector on board the Ulysses spacecraft. Later on, interstellar dust was also identified in the data sets measured with dust instruments on board Galileo, Cassini, and Helios. Ulysses monitored the interstellar dust stream at high ecliptic latitudes for about 16 yr. The three other spacecraft data sets were obtained in the ecliptic plane and cover much shorter time intervals. Aims. To test the reliability of the model predictions, we compare previously published in situ interstellar dust measurements, obtained with these four spacecraft, with predictions of an advanced model for the dynamics of interstellar dust in the inner solar system (Interplanetary Meteoroid environment for EXploration; IMEX). Methods. Micrometer and sub-micrometer-sized dust particles are subject to solar gravity, radiation pressure and the Lorentz force on a charged dust particle moving through the interplanetary magnetic field. These forces lead to a complex size-dependent flow pattern of interstellar dust in the planetary system. The IMEX model was calibrated with the Ulysses interstellar dust measurements and includes these relevant forces. We study the time-resolved flux and mass distribution of interstellar dust in the solar system. Results. The IMEX model agrees with the spacecraft measurements within a factor of 2–3, including time intervals and spatial regions not covered by the original model calibration with the Ulysses data set. The model usually underestimates the dust fluxes measured by the space missions which were not used for the model calibration, i.e. Galileo, Cassini, and Helios. Conclusions. A unique time-dependent model, IMEX is designed to predict the interstellar dust fluxes and mass distributions for the inner and outer solar system. The model is suited to study dust detection conditions for past and future space missions. [ABSTRACT FROM AUTHOR]

Interplanetary dust particles and meteoroids mostly originate from comets and asteroids. Understanding their distribution in the Solar system, their dynamical behavior and their properties, sheds light on the current state and the dynamical behavior of the Solar system. Dust particles can endanger Earth-orbiting satellites and deep-space probes, and a good understanding of the spatial density and velocity distribution of dust and meteoroids in the Solar system is important for designing proper spacecraft shielding. The study of interplanetary dust and meteoroids provides clues to the formation of the Solar system. Particles having formed 4.5 billion years ago can survive planetary accretion and those that survived until now did not evolve significantly since then. Meteoroids and interplanetary dust can be observed by measuring the intensity and polarization of the zodiacal light, by observing meteors entering the Earth's atmosphere, by collecting them in the upper atmosphere, polar ices and snow, and by detecting them with in-situ detectors on space probes. [ABSTRACT FROM AUTHOR]

The DESTINY + spacecraft will be launched to the active asteroid (3200) Phaethon in 2025. The spacecraft will be equipped with the DESTINY + Dust Analyzer (DDA) which will be a time-of-flight impact ionization mass spectrometer. In addition to the composition of impacting dust particles, the instrument will measure the particle mass, velocity vector, and surface charge. Here, we study the detection conditions of DDA for interstellar dust during the DESTINY + mission. We use the interstellar dust module of the Interplanetary Meteoroid environment for EXploration model (IMEX Sterken et al., 2013; Strub et al., 2019) to simulate the flow of interstellar dust through the Solar System. Extending earlier work by Krüger et al. (2019b) we consider the entire DESTINY + mission, i.e. the Earth-orbiting phase of the spacecraft during the initial approximately 1.5 years after launch, the nominal interplanetary mission phase up to the Phaethon flyby, and a four-years mission extension beyond the Phaethon flyby. The latter may include additional asteroid flybys. For predicting dust fluxes and fluences we take into account a technical constraint for DDA not to point closer than 90 ° towards the Sun direction for health and safety reasons of the instrument and in order to avoid electrical noise generated by photoelectrons. For the Earth orbiting phase after launch of DESTINY + our simulations predict that up to 28 interstellar particles will be detectable with DDA in 2026. In the following years the interplanetary magnetic field changes to a focussing configuration for small (≲ 0. 1 μ m) interstellar dust particles. This increases the total number of detectable particles to 50 during the interplanetary mission of DESTINY + in 2027. In 2028 and 2029/30 approximately 160 and 190 particles will be detectable, respectively, followed by about 500 in 2030/31. We also make predictions for the detectability of organic compounds contained in the interstellar particles which is a strong function of the particle impact speed onto the detector. While organic compounds will be measurable only in a negligible number of particles during the Earth orbiting and the nominal interplanetary mission phases, a few 10s of interstellar particle detections with measurable organic compounds are predicted for the extended mission from 2028 to 2031. • The DESTINY+ spacecraft will be launched to the active asteroid (3200) Phaethon in 2025. The spacecraft will be equipped with the DESTINY+ Dust Analyzer (DDA) which will be a time-of-flight impact ionization mass spectrometer. • We use the interstellar dust module of the Interplanetary Meteoroid environment for EXploration model (IMEX) to simulate the detection conditions for interstellar dust with DDA. • Our results show that DDA will be able to detect and analyze several hundred interstellar dust particles during its nominal and extended interplanetary mission. [ABSTRACT FROM AUTHOR]