New Horizons/Alice UV-spectrograph measurements of the cosmic ultraviolet background (CUVB) at high Galactic latitudes, taken at ~57 AU beyond most of the interplanetary foreground that limited earlier missions. Determines the CUVB spectrum across 912-1100 A and 1400-1800 A, finds a linear correlation with Planck E(B-V) dust reddening with nonzero zero-reddening offsets (~4-5 nW m^-2 sr^-1), attributes about half to known sources (unresolved galaxies and stars, ionized-gas and two-photon halo emission) and leaves the remainder unidentified, and sets an upper limit on emission below the Lyman limit.
New Horizons/Alice UV-spectrograph measurements of the cosmic ultraviolet background (CUVB) at high Galactic latitudes (|b|>40 deg), taken at about 57 AU from the Sun, beyond most of the interplaneta…