Here's What You Need To Remember: If the Tsar Bomba explosion was a stunt, the other biggest Soviet tests weren't. 1962 was the last year of atmospheric nuclear tests for the Soviet Union and the United States, and both sides rushed to prove weapon designs.

The Bomb represents the ultimate expression of might, so the biggest bombs express that power to its extremes. The United States and the Soviet Union built bigger and bigger bombs to deter each other. Eventually, Washington stopped testing such large weapons due to improved accuracy of their delivery methods. Only 3 percent of the superpowers' stockpiles consisted of nuclear weapons with yields greater than four megatons, but those weapons more than any others symbolize the terror of nuclear war.

The Soviet Union's swift strides towards nuclear arms alarmed American officials in the 1950’s. "First Lightning" (called "Joe-1" in the West)—the first Soviet nuclear test—announced Moscow's new military power less than three months after lifting the Berlin Blockade in May 1949. The twenty-two-kiloton shot copied the U.S. Trinity test as closely as possible to achieve early success; the rushed development actually stalled the Soviet program for over a year, with the second test occurring in September 1951.

This phase of the Cold War went hot on the Korean Peninsula and President Truman gave the go-ahead for the "Super," as it was called. Edward Teller—a brilliant, vain and pugnacious physicist who fled Hungary for the United States to join the Manhattan Project—was smitten by the idea of thermonuclear fusion and argued forcefully for U.S. research into bigger bombs. Pursuit of the "Super" alarmed Soviet leaders and scientists. As they explored the possibility, however, the Soviets had an advantage over the Americans: lithium.

The first-ever hydrogen bomb blast, Ivy Mike, required American weaponeers to create an vast new industrial capacity for manufacturing liquid hydrogen in its "heavy" form of liquid deuterium. The Ivy Mike device was liquid-fueled and a handful of emergency-capability (EC) liquid-fuel bombs were later built; several B-36 bombers were modified to top off the liquid hydrogen in flight en route to their targets.

But the Soviets dispensed with liquid fuel for dry powdered lithium deuteride, a chemical compound of lithium metal and hydrogen gas. Lithium comes in two "flavors" or isotopes: Lithium-6 and Lithium-7. Lithium-7 was thought by both sides to be inert and unsuitable as bomb fuel. The Soviet Union had plentiful sources of Lithium-7, but the United States did not. As a result, Soviet weaponeers worked on dry-fuel bombs from the start. The fourth Soviet nuclear test in 1953 registered an impressive 400 kilotons from the "Sloika" design.

America’s disastrous Castle Bravo H-bomb test in 1954 revealed Lithium-6's fusion potential and provided the Soviet Union with needed information; a mere eighteen months elapsed between the Castle Bravo test and the Soviet test of November 1955: an air drop of a fully weaponized hydrogen bomb. At 1.6 megatons, the yield of RDS-37 was impressive—but it would be dwarfed by the monsters to come.

In 1958 the Soviet Union matched the America’s voluntary moratorium on nuclear testing; in September 1961, after raising the Berlin Wall, Nikita Khrushchev ordered testing resumed. On October 23, a 12.5-megaton airdrop pounded the high Arctic island of Novaya Zemlya. The resulting blast was nearly as large as Castle Yankee—America's second biggest test—but only the Soviet Union’s fifth-biggest.

The biggest bomb ever built or tested—the RDS-220 ("Big Ivan" or "Tsar Bomba")—rattled the planet one week later on October 30, 1961. The result of a crash program directed by Andrei Sahkarov, the Tsar Bomba was a conservative design accomplished with astonishing speed: in only four months. The 100-megaton (possibly 150-megaton) design was an impractical weapon—only a single modified Bear bomber could carry it, slowly—but a billy-hell of a propaganda show.

Even though Sakharov had the third-stage fission tampers replaced with inert lead due to concerns about fallout, the Tsar Bomba still yielded fifty-six megatons, enough to blow a hole in the atmosphere and cause damage hundreds of miles away. Had the third stage tampers been uranium this one bomb would have raised global fallout levels by 25 percent. Every person born before October 1961 has bits of the Tsar Bomba (and other bombs) in their bodies to this day.

If the Tsar Bomba explosion was a stunt, the other biggest Soviet tests weren't. 1962 was the last year of atmospheric nuclear tests for the Soviet Union and the United States, and both sides rushed to prove weapon designs. The fourth, third and second largest Soviet nuclear tests all seem related to ICBM-warhead development: Test 147 on August 5, 1962 yielded over twenty-one megatons; Test 173 nineteen megatons; and Test 219 a whopping 24.2 megatons—nearly half the Tsar Bomba's yield.

This city-busting warhead wound up on R-36 ICBMs (NATO designation SS-18 "Satan"), huge missiles capable of obliterating deeply buried targets or entire metro areas. Although photos and data from Test 219 are not publicly available, Alex Wellerstein's NUKEMAP drives home the power of such a bomb. Dropped on downtown Los Angeles, the air blast would level the Coliseum (four miles away) and burn down all of Beverly Hills (nine miles away).

Steve Weintz, a frequent contributor to many publications such as WarIsBoring, is a writer, filmmaker, artist and animator. This first appeared two years ago.

Image: Wikipedia.