Light is precisely one form of energy that is easiest for humans to understand.
Since the birth of Earth 4.55 billion years ago, it has been illuminated by the sun's light for 4.55 billion years.
In Earth's long history, life has originated, cell structures have become complex, and microorganisms, plants, and animals have formed.
Plants are the producers among them.
The meaning of a producer is to use sunlight as an energy source, complete photosynthesis, form organic matter, which is eventually consumed and utilized by animals and nature, and ultimately returns as heat energy.
This heat energy is constantly dispersed into the universe through the atmosphere.
If we assume the atmosphere is confined inwards and heat energy cannot disperse, then the Earth's mass must be continually increasing.
The increased mass is the weight of light.
