Effects radii for 1e+25 kt blast (smallest to largest):
Radiation radius: 47248.87 km / 29359.08 mi
500 rem radiation dose; between 50% and 90% mortality from acute effects alone; dying takes between several hours and several weeks.
Air blast radius: 49791823.48 km / 30939204.72 mi
20 psi overpressure; heavily built concrete buildings are severely damaged or demolished; fatalities approach 100%.
Air blast radius: 131425548.18 km / 81664049.56 mi
4.6 psi overpressure; most buildings collapse; injuries universal, fatalities widespread.
Fireball radius: 303030303.03 km / 188294300.68 mi
Maximum size of the nuclear fireball; relevance to lived effects depends on height of detonation.
Thermal radiation radius: 12213625419.14 km / 7589194988.23 mi
Third-degree burns to all exposed skin; starts fires in flammable materials, contributes to firestorm if large enough.
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