Introduction: We developed a dust mass spectrometer (SUrface Dust Analyser SUDA) to measure the composition of ballistic dust particles populating the thin exosphere that was detected around Europa. Because these grains are samples from the moon’s icy surface, unique information will be obtained about the grains’ composition, constraining geological activities on and below the moon’s surface. The instrument will contribute significantly to answer main scientific questions of NASA’s Europa Clipper mission, in particular about the surface composition, habitability, the icy crust, and exchange processes with the deeper interior of Jovian icy moon Europa. Dust Exoclouds: The basic idea of compositional mapping [1] [2] is that moons without an atmosphere are wrapped in clouds of dust particles ejected by meteoroid impacts from the moon's surfaces, whose composition can be analysed by and detected by an orbiter instrument. The ejecta production process is very efficient: a typical interplanetary 10 kg micrometeoroid impact on Europa produces a large number of dust particles with a total mass about 18 thousand times of the imp actor’s mass [3]. The so-called ejecta particles move on ballistic trajectories and most of them recollide with the moon. As a consequence, an almost isotropic dust cloud forms around the moon [4] [5]. In 1999, the Galileo dust instrument measured the density profiles of the tenuous dust exospheres around each of the Galilean satellites [6]. The cloud density declines asymptotically with the distance as r. This implies that a spacecraft in close orbits around Europa will be hit by a substantial number of eject arriving from apex direction with approximately spacecraft speed. The dynamic properties of the cloud particles are clearly distinct from any other kind of cosmic dust likely to be detected in the vicinity of the satellite. Compositional Mapping: For every dust particle detected in the vicinity of the moon, the SUDA instrument is capable of constraining the location of origin on the surface. This enables the correlation of the measured dust composition to geologic features on the surface. This is accomplished by measuring the particles’ velocity along the instrument axis to infer the most likely distance of the particle origin from the subspacecraft point with a possible resolution of a few tens of kilometers (Fig. 1). This allows simultaneous compositional mapping of many organic and inorganic components, including both major and trace compounds, with a single instrument.