Yes, Vaseline glows in the dark under specific conditions. More precisely, Vaseline (petroleum jelly) glows a bright blue color when exposed to a black light or ultraviolet (UV) light.
Understanding the Fluorescence of Vaseline
The "glow" isn't actually Vaseline emitting light on its own. Instead, it's a phenomenon called fluorescence. Fluorescence occurs when a substance absorbs light (in this case, UV light from a black light) and then re-emits light of a different wavelength (resulting in the visible blue glow).
Why Use a Black Light?
A black light emits ultraviolet light, which is invisible to the human eye. Certain substances, like petroleum jelly, react to this UV light and emit visible light, making them appear to glow. According to provided reference, petroleum jelly, such as Vaseline, glows bright blue under a black light.
Practical Applications
This property of Vaseline (and other fluorescent substances) has some practical uses:
- Security Marking: While the reference mentions security markings, the glowing property of substances under UV light allows for the easy detection of those markings. This is similar to how clubs will use stamps with invisible ink that glow under black lights to verify entry.
Examples of Other Fluorescent Items
Interestingly, Vaseline isn't the only common household item that fluoresces. For example:
- Ripe bananas glow fluorescent blue under a black or ultraviolet lamp, as mentioned in the provided reference.
