Chapter 4 · Cosmic Background

Racing through the cosmic microwave background

Measured against the faint afterglow of the Big Bang, our Local Group is hurtling through space at about 1.3 million mph (2.1 million km/h) — the fastest motion we can reliably attach to ourselves.

Velocity relative to the CMB

You are moving through the universe

1,300,000mph
2,100,000km/h

Distance traveled through the CMB while viewing this page

0 mi·0 km

Time on page: 0.0s

A note on adding these speeds

The CMB velocity already includes Earth's spin, its orbit around the Sun, and the Sun's orbit around the Milky Way — those smaller motions are the ingredients astronomers subtract to isolate it. Because every ingredient points in a different direction, you can't strictly add them together — the ~1.3 million mph figure is the net result, not a sum of the previous chapters.