The diffuse galactic light, resulting from the coherent scattering of galactic starlight by dust grains contained in the general interstellar medium, has been the subject of active investigation for nearly 60 years. The separation of the diffuse galactic light from the other sources contributing to the light from the night sky has proven difficult, and different attempts at measuring the intensity and galactic distribution of the diffuse galactic light, both in the visible and the UV, are

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... ed here. The interpretation of such measurements in terms of average scattering properties of interstellar grains is subject to additional uncertainties, stemming from the high degree of idealization imposed on the galaxy models used to study the radiative transfer problem. In the visible, the observations are more nearly definitive and the model problems less severe; reasonably consistent scattering properties have therefore been derived for this spectral region. In the UV, the situation is considerably less satisfactory, mainly due to a lack of sufficiently extensive, reliable measurements of the diffuse galactic light intensity at λ < 200 nm. A dedicated space mission may be the required solution. The radiative transfer in the UV presents serious difficulties due to the increasing opacity of the interstellar medium with shorter wavelengths and the resulting growing importance of the local galactic structure.