Emission is the opposite of absorption, it is when an object emits radiation. Objects tend to emit amounts and wavelengths of radiation depending on their "black body" emission curves, therefore hotter objects tend to emit more radiation, with shorter wavelengths. Colder objects emit less radiation, with longer wavelengths. For example, the Sun is approximately 6,000 K (5,730 °C; 10,340 °F), its radiation peaks near 500 nm, and is visible to the human eye. Earth is approximately 290 K (17 °C; 62 °F), so its radiation peaks near 10,000 nm, and is much too long to be visible to humans. The light that is observed on photographs of earth from space and with the naked eye is only reflected visible light.
Sarah is an astrophysicist studying the properties of two newly discovered stars: Star S and Star T. Not much is known about the stars other than the temperature, and Sarah only knows that Star S is much hotter than Star T.
Which star will emit less radiation?