Astronomy and Cosmology

Standard Candles Luminosity Luminosity (L) The total power of radiation emitted by a star, measured in watts (W). Luminosity is an intrinsic property of a star…

Stellar Radii Wien's Displacement Law All objects emit electromagnetic radiation. The wavelength at which the radiation intensity is maximum depends on the…

Hubble's Law and the Big Bang Theory Redshift of Spectral Lines When we observe the spectra of distant galaxies, we find that the emission and absorption lines…