No definite conclusion is possible. An interesting possibility is
raised, however, that
deserves observational and theoretical exploration. The intergalactic
clouds of ionized
hydrogen that we postulate might be related to the objects that produce
the Lyman
forest, and the extrapolated spectrum of the radiation approximates the
integrated light of the faint blue "galaxies" discovered by
Tyson (1988).
Perhaps Tyson's objects are
not galaxies at all, but our gaseous objects, radiating and dissipating.
Diffuse ultraviolet background study today is in the same state that study of the diffuse infrared background was before IRAS and COBE: fragmentary, often conflicting observations. What is needed is an all-sky survey in the ultraviolet, involving both imaging and spectroscopy.
This work was supported by United States Air Force Contract F19628-93-K-0004, and by National Aeronautics and Space Administration grant NASA NAG5-619. We are grateful for the encouragement of Dr. Stephan Price.