Atmospheric Reentry: Compression Heating, Not Friction
Reentry heat comes from compression heating (not friction), creating 1,600-8,000°C plasma. Vacuum exposure allows 10-15s consciousness and 60-90s survival — no explosive decompression occurs.
A common misconception is that atmospheric reentry heat comes from friction. The actual mechanism is compression heating: the spacecraft compresses air ahead of it faster than it can move aside, creating a shockwave that heats the compressed air to plasma temperatures of 1,600-8,000°C at orbital velocities. Distinctions by scenario: - Orbital reentry (7.8+ km/s): extreme compression heating, requires heat shields - High-altitude non-orbital drop (e.g. from a high-altitude platform, not at orbital velocity): negligible heating, but requires a pressure suit and supplemental oxygen Vacuum exposure survival: a human remains conscious for 10-15 seconds after sudden exposure to vacuum, with a survival limit of approximately 60-90 seconds. Contrary to popular depiction, there is no explosive decompression — human skin is strong enough to contain internal pressure.