Extended red emission (ERE) has been detected in many dusty astrophysical objects, raising the ques- tion of whether ERE is present only in discrete objects or if it is an observational feature of all dust, i.e., present in the diffuse interstellar medium. In order to answer this question, we determined the blue and red intensities of the radiation from the diffuse interstellar medium(ISM) and examined the red intensity for the presence of an excess above the expected for scattered light. The diffuse ISM blue and red inten- sities were obtained by subtracting the integrated star and galaxy intensities from the blue and red mea- surements made by the Imaging Photopolarimeters(IPPs) aboard the Pioneer 10 and 11 spacecraft.
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