Empirical Earth · Gravity, Buoyancy & the Air

Gas next to vacuum — no dome required

The claim

“Gas can’t touch a vacuum without a container, so we’re sealed under a dome.”

What is measured

Air pressure falls off exponentially with height, halving roughly every 5.5 km, which only happens if gravity binds a gas shell to a planet. See also the atmosphere as an open system and the gas laws and gravity.

What would show this is wrong

a measured pressure-vs-altitude profile that did not fall off exponentially under gravity.

Sources

  1. Atmospheric structure, scale height & escape. Pressure falls exponentially, H = kT/(mg) ≈ 8.5 km; no hard boundary (Kármán line is a 100 km convention); thermal/Jeans escape slowly leaks lig link
  2. Pressure as the weight of air; the ISS in the upper atmosphere. Sea-level pressure (~101 kPa) is the weight of the overlying air; it falls smoothly with height (Everest ~1/3 sea level), and link
  3. The geocorona extends past the Moon. SOHO/SWAN Lyman-alpha mapping (Baliukin et al., 2019) found Earth’s hydrogen geocorona, the outer exosphere, reaching about 630,000 km, some 50 Earth dia link
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