Canopus

Test deviceFranceThermonuclear (staged)

No freely licensed photo of this device yet.

Yield · TNT equivalent2.6 Mt

Key specs

Country: France
Design: Thermonuclear (staged)
Type: Test device
Number built: 1

Overview

France’s first two-stage thermonuclear test: a 2.6 Mt device suspended from a balloon over Fangataufa Atoll in August 1968, making France the fifth country to test a hydrogen bomb.

Effect radii: estimates

Calculated for 2.6 Mt

Fireball, maximum radius: ≈ 1.4 km
Initial radiation, 500 rem (5 Sv): ≈ 3.7 km
Blast 5 psi: most buildings collapse: ≈ 9.8 km
Thermal: third-degree burns: ≈ 17 km
Blast 1 psi: windows shatter: ≈ 30 km

Estimated ground ranges for an air burst at the optimum height over flat, open ground, computed from the yield with standard scaling laws. These are not measurements: real effects depend on the height of burst, terrain, buildings and weather.

Formulas from: Glasstone & Dolan, The Effects of Nuclear Weapons (1977), chapter II; Carey Sublette, Nuclear Weapons FAQ, section 5

Tests and use

Date	Event	Site	Yield
Aug 24, 1968	Canopus	Fangataufa Atoll, French Polynesia	2.6 Mt

Sources

Canopus (nuclear test), Wikipedia