1.   But even Nikitin said the radiation would come from the cooling water, not the reactor fuel.

2.   Electromagnetic radiation comes in many wavelengths, ranging from the longest -- radio waves -- through infrared, visible light, ultraviolet, X-rays and gamma rays.

3.   Such radiation could have come only from a large population of stars at redshifts beyond that of the quasars.

4.   The gamma radiation may come from sprites and blue jets, although direct proof is lacking.