At no point is U-235 "glowing." It's unlikely to even be warm. In a cloud chamber a reasonably small chunk will look interesting, but far below the activity of Americium that is used in home ionization detectors for fire alerting.
Yep. U-235 is actually not very radioactive, with a half life of approximately 700 million years. For reference, the shorter the half life the more radioactive emissions. For example, P-238 has a half life of about 88 years and is used in space craft for thermo-electric generators because of its heat of decay. P-239, used in weapons, has a half life of about 24,000 years. Not nice stuff, but atomic bomb pits were handled in open air back in the Los Alamos days; just don't breath the dust.