&lt;p&gt;
	We propose to develop a new highly sensitive instrument to confirm the existence of the so-called nano-dust particles, characterize their impact parameters, and measure their chemical composition. Simultaneous theoretical studies will be used to derive the expected&amp;nbsp; mass and velocity ranges of these putative particles to formulate science and measurement requirements for the future deployment of&amp;nbsp; the proposed Nano-Dust Analyzer (NDA)&amp;nbsp;&lt;/p&gt;
&lt;p&gt;
	Early dust instruments onboard Pioneer 8 and 9 and Helios spacecraft detected a flow of submicron sized dust particles coming from the direction of the Sun. These particles originate in the inner solar system from mutual collisions among meteoroids and move on&amp;nbsp; hyperbolic orbits that leave the Solar System under the prevailing radiation pressure force. Later dust instruments with higher&amp;nbsp; sensitivity had to avoid looking toward the Sun because of interference from the solar wind and UV radiation and thus contributed&amp;nbsp; little to the characterization of the dust stream. The one exception is the Ulysses dust detector that observed escaping dust particles&amp;nbsp; high above the solar poles, which confirm the suspicion that charged nanometer sized dust grains are carried to high heliographic&amp;nbsp; latitudes by electromagnetic interactions with the Interplanetary Magnetic Field (IMF). Recently, the STEREO WAVES instruments&amp;nbsp; recorded a large number of intense electric field signals, which were interpreted as impacts from nanometer sized particles striking the&amp;nbsp; spacecraft with velocities of about the solar wind speed. This high flux and strong spatial and/or temporal variations of nanometer&amp;nbsp; sized dust grains at low latitude appears to be uncorrelated with the solar wind properties. This is a mystery as it would require that&amp;nbsp; the total collisional meteoroid debris inside 1 AU is cast in nanometer sized fragments. The observed fluxes of inner-source pickup ions&amp;nbsp; also point to the existence of a much enhanced dust population in the nanometer size range.&amp;nbsp;&lt;/p&gt;
&lt;p&gt;
	This new heliospherical phenomenon of nano-dust streams may have consequences throughout the planetary system, but as of yet no dust instrument exists that could be used to shed light on their properties. &amp;nbsp;We propose to develop a dust analyzer capable to detect and&amp;nbsp; analyze these mysterious dust particles coming from the solar direction and to embark upon complementary theoretical studies to&amp;nbsp; understand their characteristics. The instrument is based on the Cassini Dust Analyzer (CDA) that has analyzed the composition of&amp;nbsp; nanometer sized dust particles emanating from the Jovian and Saturnian systems but could not be pointed towards the Sun. By&amp;nbsp; applying technologies implemented in solar wind instruments and coronagraphs a highly sensitive dust analyzer will be developed and&amp;nbsp; tested in the laboratory. The dust analyzer shall be able to characterize impact properties (impact charge and energy distribution of&amp;nbsp; ions from which mass and speed of the impacting grains may be derived) and chemical composition of individual nanometer sized&amp;nbsp; particles while exposed to solar wind and UV radiation. The measurements will enable us to identify the source of the dust by&amp;nbsp; comparing their elemental composition with that of larger micrometeoroid particles of cometary and asteroid origin and will reveal&amp;nbsp; interaction of nano-dust with the interplanetary medium by investigating the relation of the dust flux with solar wind and IMF&amp;nbsp; properties.&amp;nbsp;&lt;/p&gt;
&lt;p&gt;
	Complementary theoretically studies will be performed to understand the characteristics of nano-dust particles at 1 AU to answer the&amp;nbsp; following questions:&amp;nbsp; - What is the speed range at which nanometer sized particles impact a spacecraft at 1 AU?&amp;nbsp; - From what direction these particles impact at a spacecraft at 1 AU? This has implications on the field-of-view of the instrument.&amp;nbsp; - What is the flux of particles at 1 AU assuming a break-up of approximately 10 tons/sec of cosmic material (approx. 10^25 particles) in&amp;nbsp; the inner solar system?&amp;nbsp; FORM NRESS-&amp;nbsp;&lt;/p&gt;