Indeed, we can see stars and planets while particles of cosmic dust are only detectable since they change spectra of stars’ radiation reddening them. As light passes through interstellar cosmic dust, its particles absorb blue photons more than the red ones and then emit infrared as any solids do. This is why the star’s light is getting more red. The ultraviolet radiation of young stars is almost totally converted to the infrared radiation of interstellar dust. The infrared emitted by the cosmic dust constitute one third of that from all the stars. Besides, the radiation of cosmic dust cools down the neighborhood, which often creates the matter density sufficient for formation of new stars. Specifically, a molecular-dust clouds collapse due to gravity and thereby heat up. This thermal energy is being released basically via rotational radiation of carbon oxide. Moreover the radiation emitted by cosmic dust is polarized. This is because dust particles are oblong and include molecules of paramagnetic metals so that they line up along the lines of interstellar magnetic field. Photo ionization can make particles of dust charged so they revolve in the interstellar magnetic field, typically along a circumference of 0.03 pc radius. This is less then the scale of intragalactic structures so cosmic dust sticks with the magnetic field.
About the Dark River 🙂