As per Wikipedia ...
... 0.3 atoms per cubic centimeter; less dense than the average for the interstellar medium in the Milky Way (0.5 atoms/cm3), though six times denser than the gas in the Local Bubble (0.05 atoms/cm3) which surrounds the local cloud. In comparison, Earth's atmosphere at the edge of space has 12 billion atoms per cubic centimeter, dropping to 52 million at 150 km.
Soooooo ... yeah. ( Emphasis mine ... footnotes redacted. )
... and how about those Broncos!