Radiative heat transfer is the process by which heat energy is transferred through electromagnetic radiation. Unlike conduction and convection, which require a medium (solid or fluid) to transfer heat, radiative heat transfer can occur in a vacuum. This is why the Sun can warm the Earth despite the vast emptiness of space. In radiative heat transfer, all objects emit radiation based on their temperature. Hotter objects emit more radiation than cooler ones. The amount and type of radiation depend on the object's surface properties, described by the Stefan-Boltzmann Law and Planck's Law. This principle is essential in fields like astronomy and thermal engineering.