Answer to Question #119520 in Astronomy | Astrophysics for Nour

Question

What are the application of black body radiation in astrophysics or space physics ?with details please

Answer 1

objects and astronomical sources are only approximate black bodies. Astronomers have discovered that an almost perfect black body is represented by the Cosmic Microwave Background (CMB), the relic radiation from the Big Bang which pervades the entire Universe.

The temperature (T, in K) of an object and the wavelength at which it emits most radiation (λmax, in m) are related in the following way:

λ_max*T = 2.898 x10^-3 m K. This is usually referred to as Wien’s Displacement law.

This relation is particularly useful to astronomers as it allows them to infer the temperature of stars and other cosmic objects, which lie at enormous distances from us, by simply measuring the 'colour' of their light —more precisely, by measuring the wavelength at which their emission is most intense