At http://phys.org/print357206114.html … in 2016 NASA plans to launch a mission to asteroid Bennu in order to carry out several tasks. One is to map the Near Earth asteroid in order to detect minerals and organic molecules and search for signs of organic life. It will reach the asteroid in 2018 and return to Earth in 2023 – so a good deal of exploration is planned. Another task is to identify chemicals present on the asteroid – via infrared light.
At http://phys.org/print357214547.html … the effect of cosmic wind on dust in galaxies is an order of magnitude above the way the solar wind affects dust in the solar system – some of which has an origin in comets.
In observations of one galaxy astronomers have witnessed gas and dust clouds piled up in ridges. Low density dust and gas is dispersed by cosmic wind (or the solar wind in the case of the solar system) which is what happens to streams of dust and gas ejected from the passage of comets. However, the denser areas of such streams of material, by the same process, dissipating the small and fine elements of comet streams must also preserve the dense core of such streams. Clube and Napier saw these as potential hazards – but does the solar wind place them in an orbit safe as far as the Earth is concerned?