Equation #8: Stefan-Boltzmann Law From gamma rays to infrared to radio, we have the whole range of frequencies of electromagnetic radiation. An ideal body (although for practical purposes we can take the Sun to be one) absorbs (and emits) radiation
Exoplanets are the planets that orbit other stars. However, there are some exoplanets that have been found to be wandering alone, escaped from their host star. We can’t see them directly(even with telescopes) because: 1. They’re very far away 2.
Equation #1 The Hubble’s Law Everything in the universe appears to be moving away from each other on the cosmic scale. The larger the separation between two objects, faster is their receding velocity(measured by redshift). For more details, go see http://hyperphysics.phy-astr.gsu.edu/hbase/astro/hubble.html