What is the Cosmic Microwave Background?

Hello and welcome to the first installment of “The Interesting Part”, a weekly blog where I look in a little more depth at the Interesting Part (to my mind) of some of the week’s science news.

     For my first week, I thought I’d go a little easy on myself and pick something I already have some knowledge about. It just so happens that a topic fitting this description found its way into three different articles that I came across this week. Firstly, this article from Ars Technica talking about the so-called “cosmological axis of evil” first discussed in a 2005 paper based on WMAP data. My topic also appears in this New Scientist article from last month discussing the “mysteries” of the big bang (warning, requires subscription) and in Annalee Newitz’ piece for Slate, republished in this week’s National Post about a Avi Loeb’s suggestion of a “habitable epoch” in the early universe. The thread that ties these together? The Cosmic Microwave Background or CMB, a faint light that permeates the entire known universe, which originated before galaxies, planets or even stars began to form.

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