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Dust particle impacts on the Wind spacecraft were detected with its plasma wave instrument Wind/WAVES. Frequency analysis on this dust impact time series revealed spectral peaks indicative of a solar rotation signature. We investigated whether this solar rotation signature is embedded in the interplanetary or interstellar dust (ISD) and whether it is caused by co-rotating interaction regions (CIRs), by the sector structure of the interplanetary magnetic field (IMF), or by external effects. We performed frequency analysis on subsets of the data to investigate the origin of these spectral peaks, comparing segments of Wind's orbit when the spacecraft moved against or with the ISD inflow direction and comparing the time periods of the ISD focusing and defocusing phases of the solar magnetic cycle. A superposed epoch analysis of the number of dust impacts during CIRs was used to investigate the systematic effect of CIRs. Case studies of time periods with frequent or infrequent occurrences of CIRs were compared to synthetic data of dust impacts affected by CIRs. We performed similar case studies for time periods with a stable or chaotic IMF sector structure. The superposed epoch analysis was repeated for a time series of the spacecraft floating potential. Spectral peaks were found at the solar rotation period of ~27d and its harmonics at 13.5d and 9d. This solar rotation signature may affect both interplanetary and ISD. The appearance of this signature correlates with the occurrence of CIRs but not with the stability of the IMF sector structure. The CIRs cause, on average, a reduction in the number of dust impact detections. Periodic changes of the spacecraft's floating potential were found to partially counteract this reduction by enhancing the instrument's sensitivity to dust impacts; these changes of the floating potential are thus unlikely to be the cause of the solar rotation signature.

We discuss the synergies between heliospheric and dust science, the open science questions, the technological endeavors and programmatic aspects that are important to maintain or develop in the decade to come. In particular, we illustrate how we can use interstellar dust in the solar system as a tracer for the (dynamic) heliosphere properties, and emphasize the fairly unexplored, but potentially important science question of the role of cosmic dust in heliospheric and astrospheric physics. We show that an Interstellar Probe mission with a dedicated dust suite would bring unprecedented advances to interstellar dust research, and can also contribute-through measuring dust - to heliospheric science. This can, in particular, be done well if we work in synergy with other missions inside the solar system, thereby using multiple vantage points in space to measure the dust as it `rolls' into the heliosphere. Such synergies between missions inside the solar system and far out are crucial for disentangling the spatially and temporally varying dust flow. Finally, we highlight the relevant instrumentation and its suitability for contributing to finding answers to the research questions., Comment: 18 pages, 7 Figures, 5 Tables. Originally submitted as white paper for the National Academies Decadal Survey for Solar and Space Physics 2024-2033

The main objective of this chapter is to present an overview of the different areas of key technologies that will be needed to fly the technically most challenging of the representative missions identified in chapter 4 (the Pillar 2 Horizon 2061 report). It starts with a description of the future scientific instruments which will address the key questions of Horizon 2061 described in chapter 3 (the Pillar 1 Horizon 2061 report) and the new technologies that the next generations of space instruments will require (section 2). From there, the chapter follows the line of logical development and implementation of a planetary mission: section 3 describes some of the novel mission architectures that will be needed and how they will articulate interplanetary spacecraft and science platforms; section 4 summarizes the system-level technologies needed: power, propulsion, navigation, communication, advanced autonomy on board planetary spacecraft; section 5 describes the diversity of specialized science platforms that will be needed to survive, operate and return scientific data from the extreme environments that future missions will target; section 6 describes the new technology developments that will be needed for long-duration missions and semi-permanent settlements; finally, section 7 attempts to anticipate on the disruptive technologies that should emerge and progressively prevail in the decades to come to meet the long-term needs of future planetary missions., Comment: 100 pages, 23 figures, Horizon 2061 is a science-driven, foresight exercise, for future scientific investigations

This chapter of the Planetary Exploration Horizon 2061 Report reviews the way the six key questions about planetary systems, from their origins to the way they work and their habitability, identified in chapter 1, can be addressed by means of solar system exploration, and how one can find partial answers to these six questions by flying to the different provinces to the solar system: terrestrial planets, giant planets, small bodies, and up to its interface with the local interstellar medium. It derives from this analysis a synthetic description of the most important space observations to be performed at the different solar system objects by future planetary exploration missions. These observation requirements illustrate the diversity of measurement techniques to be used as well as the diversity of destinations where these observations must be made. They constitute the base for the identification of the future planetary missions we need to fly by 2061, which are described in chapter 4. Q1- How well do we understand the diversity of planetary systems objects? Q2- How well do we understand the diversity of planetary system architectures? Q3- What are the origins and formation scenarios for planetary systems? Q4- How do planetary systems work? Q5- Do planetary systems host potential habitats? Q6- Where and how to search for life?, Comment: 107 pages, 37 figures, Horizon 2061 is a science-driven, foresight exercise, for future scientific investigations

Owing to the ever-present solar wind, our vast solar system is full of plasmas. The turbulent solar wind, together with sporadic solar eruptions, introduces various space plasma processes and phenomena in the solar atmosphere all the way to the Earth's ionosphere and atmosphere and outward to interact with the interstellar media to form the heliopause and termination shock. Remarkable progress has been made in space plasma physics in the last 65 years, mainly due to sophisticated in-situ measurements of plasmas, plasma waves, neutral particles, energetic particles, and dust via space-borne satellite instrumentation. Additionally high technology ground-based instrumentation has led to new and greater knowledge of solar and auroral features. As a result, a new branch of space physics, i.e., space weather, has emerged since many of the space physics processes have a direct or indirect influence on humankind. After briefly reviewing the major space physics discoveries before rockets and satellites, we aim to review all our updated understanding on coronal holes, solar flares and coronal mass ejections, which are central to space weather events at Earth, solar wind, storms and substorms, magnetotail and substorms, emphasizing the role of the magnetotail in substorm dynamics, radiation belts/energetic magnetospheric particles, structures and space weather dynamics in the ionosphere, plasma waves, instabilities, and wave-particle interactions, long-period geomagnetic pulsations, auroras, geomagnetically induced currents (GICs), planetary magnetospheres and solar/stellar wind interactions with comets, moons and asteroids, interplanetary discontinuities, shocks and waves, interplanetary dust, space dusty plasmas and solar energetic particles and shocks, including the heliospheric termination shock. This paper is aimed to provide a panoramic view of space physics and space weather., Comment: Accepted for publication in IEEE Transactions on Plasma Science (2022)

We summarize evidence that multiple supernovae exploded within 100 pc of Earth in the past few Myr. These events had dramatic effects on the heliosphere, compressing it to within ~20 au. We advocate for cross-disciplinary research of nearby supernovae, including on interstellar dust and cosmic rays. We urge for support of theory work, direct exploration, and study of extrasolar astrospheres., Comment: White paper submitted to the Solar and Space Physics 2024 Decadal Survey

The JAXA/ISAS spacecraft DESTINY$^+$ will be launched to the active asteroid (3200) Phaethon in 2022. Among the proposed core payload is the DESTINY+ Dust Analyzer (DDA) which is an upgrade of the Cosmic Dust Analyzer flown on the Cassini spacecraft to Saturn (Srama et al. 2011). We use two up-to-date computer models, the ESA Interplanetary Meteoroid Engineering Model (IMEM, Dikarev et al. 2005), and the interstellar dust module of the Interplanetary Meteoroid environment for EXploration model (IMEX; Sterken2013 et al., Strub et al. 2019) to study the detection conditions and fluences of interplanetary and interstellar dust with DDA. Our results show that a statistically significant number of interplanetary and interstellar dust particles will be detectable with DDA during the 4-years interplanetary cruise of DESTINY+. The particle impact direction and speed can be used to descriminate between interstellar and interplanetary particles and likely also to distinguish between cometary and asteroidal particles., Comment: 40 pages, 18 Figures, accepted for Planetary and Space Science

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 years. The three other spacecraft data sets were obtained in the ecliptic plane and cover much shorter time intervals.We compare in-situ interstellar dust measurements obtained with these four spacecrafts, published in the literature, with predictions of a state-of-the-art model for the dynamics of interstellar dust in the inner solar system (Interplanetary Meteoroid environment for EXploration, IMEX), in order to test the reliability of the model predictions. Micrometer and sub-micrometer sized dust particles are subject to solar gravity and radiation pressure as well as to the Lorentz force on a charged dust particle moving through the Interplanetary Magnetic Field. 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. The IMEX model agrees with the spacecraft measurements within a factor of 2 to 3, also for time intervals and spatial regions not covered by the original model calibration with the Ulysses data set. It usually underestimates the dust fluxes measured by the space missions which were not used for the model calibration, i.e. Galileo, Cassini and Helios. IMEX is a unique time-dependent model for the prediction of 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., Comment: 24 pages, 7 figures, 1 table

Aims. Based on measurements by the Ulysses spacecraft and high-resolution modelling of the motion of interstellar dust (ISD) through the heliosphere we predict the ISD flow in the inner planetary system and on to the Earth. This is the third paper in a series of three about the flow and filtering of the ISD. Methods. Micrometer- and sub-micrometer-sized dust particles are subject to solar gravity and radiation pressure as well as to interactions with the interplanetary magnetic field that result in a complex size-dependent flow pattern of ISD in the planetary system. With high-resolution dynamical modelling we study the time-resolved flux and mass distribution of ISD and the requirements for detection of ISD near the Earth. Results. Along the Earth orbit the density, speed, and flow direction of ISD depend strongly on the Earth's position and the size of the interstellar grains. A broad maximum of the ISD flux (2x10^{-4}/m^2/s of particles with radii >~0.3\mu m) occurs in March when the Earth moves against the ISD flow. During this time period the relative speed with respect to the Earth is highest (~60 km/s), whereas in September when the Earth moves with the ISD flow, both the flux and the speed are lowest (<~10 km/s). The mean ISD mass flow on to the Earth is ~100 kg/year with the highest flux of ~3.5kg/day occurring for about 2 weeks close to the end of the year when the Earth passes near the narrow gravitational focus region downstream from the Sun. The phase of the 22-year solar wind cycle has a strong effect on the number density and flow of sub-micrometer-sized ISD particles. During the years of maximum electromagnetic focussing (year 2031 +/- 3) there is a chance that ISD particles with sizes even below 0.1\mu m can reach the Earth. Conclusions. We demonstrate that ISD can be effectively detected, analysed, and collected by space probes at 1 AU distance from the Sun., Comment: 17 pages, 17 figures

The interplanetary space probe Cassini/Huygens reached Saturn in July 2004 after seven years of cruise phase. The Cosmic Dust Analyzer (CDA) measures the interplanetary, interstellar and planetary dust in our solar system since 1999 and provided unique discoveries. In 1999, CDA detected interstellar dust in the inner solar system followed by the detection of electrical charges of interplanetary dust grains during the cruise phase between Earth and Jupiter. The instrument determined the composition of interplanetary dust and the nanometre sized dust streams originating from Jupiter's moon Io. During the approach to Saturn in 2004, similar streams of submicron grains with speeds in the order of 100 km/s were detected from Saturn's inner and outer ring system and are released to the interplanetary magnetic field. Since 2004 CDA measured more than one million dust impacts characterizing the dust environment of Saturn. The instrument is one of three experiments which discovered the active ice geysers located at the south pole of Saturn's moon Enceladus in 2005. Later, a detailed compositional analysis of the water ice grains in Saturn's E ring system lead to the discovery of large reservoirs of liquid water (oceans) below the icy crust of Enceladus. Finally, the determination of the dust- magnetosphere interaction and the discovery of the extended E ring (at least twice as large as predicted) allowed the definition of a dynamical dust model of Saturn's E ring describing the observed properties. This paper summarizes the discoveries of a ten year story of success based on reliable measurements with the most advanced dust detector flown in space until today. This paper focuses on cruise results and findings achieved at Saturn with a focus on flux and density measurements., Comment: 18 pages, 12 Figures, DLRK 2011

In the early 1990s, contemporary interstellar dust (ISD) penetrating deep into the heliosphere was identified with the in-situ dust detector on board the Ulysses spacecraft. Between 1992 and the end of 2007 Ulysses monitored the ISD stream. The interstellar grains act as tracers of the physical conditions in the local interstellar medium surrounding our solar system. Earlier analyses of the Ulysses ISD data measured between 1992 and 1998 implied the existence of 'big' ISD grains [up to 10^-13kg]. The derived gas-to-dust-mass ratio was smaller than the one derived from astronomical observations, implying a concentration of ISD in the very local interstellar medium. We analyse the entire data set from 16 yr of Ulysses ISD measurements in interplanetary space. This paper concentrates on the overall mass distribution of ISD. An accompanying paper investigates time-variable phenomena in the Ulysses ISD data, and in a third paper we present the results from dynamical modelling of the ISD flow applied to Ulysses. We use the latest values for the interstellar hydrogen and helium densities, the interstellar helium flow speed of v_ISM,inf=23.2km/s, and the ratio of radiation pressure to gravity, beta, calculated for astronomical silicates. We find a gas-to-dust-mass ratio in the local interstellar cloud of R_g/d=193^+85_-57, and a dust density of 2.1+/-0.6x10^-24kg/m^3. For a higher inflow speed of 26km/s, the gas-to-dust-mass ratio is 20% higher, and, accordingly, the dust density is lower by the same amount. The gas-to-dust mass ratio derived from our new analysis is compatible with the value most recently determined from astronomical observations. We confirm earlier results that the very local interstellar medium contains 'big' (i.e. 1 um-sized) ISD grains. We find a dust density in the local interstellar medium that is a factor of three lower than values implied by earlier analyses., Comment: 51 pages, 5 Tables, 8 Figures in Astrophysical Journal, published, 812:139 (16pp), 2015 October 20

The Ulysses spacecraft provided the first opportunity to identify and study Interstellar Dust (ISD) in-situ in the Solar System between 1992 and 2007. Here we present the first comprehensive analysis of the ISD component in the entire Ulysses dust data set. We analysed several parameters of the ISD flow in a time-resolved fashion: flux, flow direction, mass index, and flow width. The general picture is in agreement with a time-dependent focussing/defocussing of the charged dust particles due to long-term variations of the solar magnetic field throughout a solar magnetic cycle of 22 years. In addition, we confirm a shift in dust direction of $50^{\circ} \pm 7^{\circ}$ in 2005, along with a steep, size-dependent increase in flux by a factor of 4 within 8 months. To date, this is difficult to interpret and has to be examined in more detail by new dynamical simulations. This work is part of a series of three papers. This paper concentrates on the time-dependent flux and direction of the ISD. In a companion paper (Kr\"uger et al., 2015) we analyse the overall mass distribution of the ISD measured by Ulysses, and a third paper discusses the results of modelling the flow of the ISD as seen by Ulysses (Sterken et al., 2015)., Comment: 41 pages, 10 figures, 5 tables