Illusion

In nature, there were very few substances that could shine on their own and they were all radioactive substances.

These substances undoubtedly contained an enormous amount of energy. Take enriched uranium for example. One gram of enriched uranium could release 20 joules of energy, which was equivalent to 1.5 tons of anthracite coal power that had the capacity to generate an output of 5555.56 kWh. This might seem insignificant, but the energy generated could melt 70 to 80 tons of steel into iron and burn people to ashes two times over.

Of course, artificial uranium had existed for a billion years. If one gram of uranium decayed naturally, it needed hundreds of billions of years to release even half its energy. The energy released in the form of radiation every second was so little, it was almost negligible.