the CMB power spectrum tells us

Ever wondered why the night sky glows uniformly?

Imagine you're looking at a perfectly dark sky, but you suddenly notice a faint, uniform glow everywhere. It's not coming from stars or planets, but it fills the entire sky.

This glow is the cosmic microwave background (CMB), the leftover radiation from the Big Bang. It's like a cosmic afterglow, filling the universe and telling us about its early moments.

Example

If you spread out 1,000 tiny lights evenly across a room, that's like the CMB filling the universe.

Remember this

The CMB is a snapshot of the universe's infancy, revealing its age, composition, and geometry.

Text adapted from Wikipedia, licensed under CC BY-SA 4.0.

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