In addition to stars and planets, space has lots of interstellar dust, although it make up only a quite modest share of all ordinary matter in the universe and can't explain dark matter phenomena. But we need to adjust other observations for dust effects to make them more precise. Our accumulated astronomy research has improves our understanding of what interstellar dust is and its properties.
Observational Constraints on the Physical Properties of Interstellar Dust in the Post-Planck Era
We present a synthesis of the astronomical observations constraining the wavelength-dependent extinction, emission, and polarization from interstellar dust from UV to microwave wavelengths on diffuse Galactic sightlines. Representative solid phase abundances for those sightlines are also derived. Given the sensitive new observations of polarized dust emission provided by the Planck satellite, we place particular emphasis on dust polarimetry, including continuum polarized extinction, polarization in the carbonaceous and silicate spectroscopic features, the wavelength-dependent polarization fraction of the dust emission, and the connection between optical polarized extinction and far-infrared polarized emission. Together, these constitute a set of constraints that should be reproduced by models of dust in the diffuse interstellar medium.