Annu. Rev. Astron. Astrophys. 1991. 29: 89-127 Copyright © 1991 by Annual Reviews. All rights reserved

6.1 Spectral Structure in the Diffuse Ultraviolet Background

The suggestion by Feldman et al (24) and of Martin & Bowyer (67) that line emission from interstellar gas, or a hot halo of the galaxy, has been detected if true would, of course, be important but cannot yet be taken as an established fact.

The discussion of Martin, Hurwitz & Bowyer (68) of fluorescence radiation of H₂ from the interstellar medium would seem to be incorrect, otherwise Voyager would have detected the radiation at shorter wavelengths. There is some controversy concerning the Voyager calibration (17), but all of the numbers that are quoted in this chapter employ the calibration of Holberg et al (44), which is conservative in the sense that the lowest Voyager upper limits that appear in Figure 15 would otherwise be substantially lower.