Interstellar dust from the local interstellar cloud passes through the solar system and gives us a chance to study it “in-situ”, using dust detectors on several space missions. In 1993, the first interstellar dust (ISD) particles were detected this way with the cosmic dust detector on the Ulysses mission. Subsequently, more ISD was discovered in the data of Helios and Galileo (retrospectively) and Cassini. In 2006, the Stardust mission brought back to Earth a few ISD particles that were captured in space and then were chemically analysed on Earth. The preliminary results were made public in the summer of 2014 and the search for more such particles in the Stardust collector continues.
In this seminar talk, I will first introduce the research field of cosmic dust in the solar system, and then focus on the ISD component that passes through the heliosphere. The complementary methods currently used to characterise this dust will be explained as well as the open issues from the observations. Specifically, the ISD dynamics will be discussed and how simulations of the ISD trajectories can be used together with the spacecraft data for constraining the dust properties. We explain what we understand and what we don’t understand yet in the Ulysses data, and propose some possible solutions.