As news of the light spread, physicists and chemists started proposing more extraordinary explanations for the radiation. Their ideas propelled Van Dover to probe deeper into the question by collaborating with geophysicist Alan D. Chave of the Woods Hole (Mass.) Oceanographic Institution and astrophysicist J. Anthony Tyson of AT&T Bell Laboratories in Murray Hill, N.J. Although they could not secure any funding to study the light, the scientists jury-rigged a photometer that measures radiation at four different frequencies, ranging from visible red light into the invisible near-infrared. Piggybacking their experiment on unrelated Alvin dives, Van Dover managed to collect some data during free moments at the tail end of expeditions to hydrothermal vents in the Atlantic and Pacific Oceans.
The scientists found more light coming off the vents than they could attribute to thermal radiation alone. At one location, they recorded 19 times the expected amount of visible red light and shorter-wavelength infrared
At another location, the photometer measured more light 10 centimeters above the vent, where the water is cooler, than at the blistering opening of the vent, report Van Dover, Chave, Tyson, and physicist George T. Reynolds of Princeton University in the Aug. 1
Geophysical Research Letters.
These observations suggest sources of light potentially more important than thermal radiation, contend Van Dover and her colleagues.
On that point, scientists can agree. "It's pretty clear there is something more going on there than just thermal radiation," comments Steven C. Chamberlain, a neuroscientist at Syracuse (N.Y.) University who has studied the shrimp eyes. "But just what is going on is not clear."