what is the source of the energy in the greenhouse? what is the source of energy entering Earth's atmosphere?

Reradiation of heat from the Earth is the source in the greenhouse, the Sun sends radiation into Earth.

The source of energy in a greenhouse is primarily the Sun. The Sun emits electromagnetic radiation, including visible light and infrared radiation. When sunlight enters the greenhouse through the transparent roof and walls, it is absorbed by the objects and surfaces inside. These objects and surfaces then re-emit the energy in the form of infrared radiation. The infrared radiation is trapped inside the greenhouse by the glass or plastic, creating a warmer environment compared to the outside.

On Earth, the primary source of energy entering the atmosphere is also the Sun. The Sun emits a continuous stream of electromagnetic radiation, particularly visible light. This sunlight travels through space and reaches the Earth's atmosphere. Approximately 30% of the incoming sunlight is reflected back into space by clouds, gases, aerosols, and reflective surfaces like ice and snow. The remaining 70% is absorbed by the Earth's surface, oceans, and atmosphere, where it warms the planet. This absorbed energy is then re-emitted as infrared radiation, warming the atmosphere and maintaining the Earth's temperature.