The H-bomb is hundreds of times more powerful than the bomb dropped on Hiroshima

The first atomic bomb used in war destroyed much of the Japanese city of Hiroshima

On August 6, 1945, the Enola Gay dropped the Little Boy atomic bomb on Hiroshima—the first combat use of a nuclear weapon. It leveled five square miles and killed tens of thousands, with accounts from both American and Japanese witnesses.

The Tsar Bomba was the most powerful nuclear weapon ever tested

In 1961, the Soviet Union detonated AN602—known as the Tsar Bomba—the largest nuclear explosion in history. Newly released Russian footage starkly illustrates the unmatched destructive power of this nuclear weapon.

Nuclear weapons release energy through rapid atomic reactions

Nuclear weapons work by unleashing energy from atomic fission—or fusion—reactions. In fission bombs, a critical mass triggers a runaway chain reaction in milliseconds. This video explains the basic science behind their immense explosive power.

How many people died in the atomic bombings remains disputed

Nearly 80 years after Hiroshima and Nagasaki, historians still disagree on the death toll from the atomic bombings. Estimates vary by up to 100,000, reflecting differences in methodology, sources, and the method used to count later radiation-related deaths.

Oppenheimer reflected on the atomic bomb's legacy two decades later

In a 1965 CBS interview, J. Robert Oppenheimer discussed his role as Los Alamos director, expressing deeply mixed feelings about Hiroshima and Nagasaki and reflecting on how nuclear weapons had transformed the world since their first use.

A US project proposed a 10-gigaton nuclear bomb capable of global devastation

Planned in the early 1950s by US scientists, Project Sundial aimed to create a 10-gigaton thermonuclear bomb—hundreds of times more powerful than any weapon ever built. Had it been tested, it was expected to cause global environmental catastrophe.

How fusion—which releases energy when two lighter atoms combine to form a heavier atom—differs from fission

Spies working on the Manhattan Project propelled the Soviet bomb program

Soviet infiltration—most notably by Klaus Fuchs—smuggled detailed implosion-design and hydrogen‑bomb data from Los Alamos to Moscow, cutting the USSR’s development time by at least a year and enabling their first atomic test in August 1949.

Every day, lightning releases several Hiroshima bombs' worth of energy into the atmosphere

If all this lightning struck one location at once, the bolt would be the diameter of the center circle of a basketball court, turning the entire court into a crater. Its heat would ignite surfaces for miles around, and its shockwave would demolish buildings.

Einstein warned the president that splitting atoms could lead to powerful bombs

In a 1939 letter to Franklin D. Roosevelt, Albert Einstein explained that nuclear fission could produce immense energy—and devastating weapons. The warning helped spur the Manhattan Project, a role Einstein later deeply regretted.

The US once had a plan to nuke the moon

In the 1950s, the US considered detonating a hydrogen bomb on the moon as part of a Cold War show of force. Known as Project A119, the classified plan aimed to create a visible explosion from Earth to signal American dominance in the Space Race.

Learn more about the three sites that powered the Manhattan Project

The Manhattan Project relied on three main sites: Oak Ridge, which enriched uranium; Hanford, which produced plutonium in large reactors; and Los Alamos, which designed and assembled the bombs—work that culminated in the Trinity nuclear test in 1945.

A breakdown of nuclear fusion and what is impeding this near-limitless clean-energy resource

While today's nuclear reactors rely on fission, which releases energy by splitting heavy atoms, nuclear fusion releases energy by combining atoms together to form more massive ones. Fusion involves overcoming repulsive forces between the centers, or nuclei, of atoms, and, as of 2026, overcoming this repulsion takes more energy than is produced.

The discovery of nuclear fission was facilitated by the discovery of the neutron

The discovery of the neutron provided scientists with a particle that could penetrate the nucleus and advance atomic physics. Otto Hahn was the sole Nobel recipient for the discovery of fission, despite collaborating with Lise Meitner and Fritz Strassmann.

The most advanced 'bunker-buster' bomb can penetrate 200 feet below soil or concrete

The GBU-57 Massive Ordnance Penetrator is delivered exclusively by the B-2 Spirit stealth bomber, which carries only two at a time. Using GPS-guided fins and a steel alloy casing, it burrows 200 feet underground before detonating.

China doubled its nuclear stockpile between 2020 and 2025, with plans for further expansion

China's arsenal grew from an estimated 300 warheads in 2020 to approximately 600 in 2025—making it the world's third-largest nuclear power. The US Department of Defense projects that China will surpass 1,000 warheads by 2030.

In 1984, Operation Smash Hit intentionally crashed a 239-ton train into a nuclear waste canister at 100 miles per hour to prove the canister's safety, which remained completely intact and lost just 0.29 of its 100 pounds of pressure.

In 1984, Operation Smash Hit intentionally crashed a 239-ton train into a nuclear waste canister at 100 miles per hour to prove the canister's safety, which remained completely intact and lost just 0.29 of its 100 pounds of pressure.

Kurt Vonnegut's 'Cat's Cradle' was inspired by the bombing of Hiroshima

The writer fought in World War II and witnessed the firebombing of Dresden, which he recounted in 1969's satirical "Slaughterhouse Five." Six years earlier, though, he wrote about the bombing of Hiroshima in "Cat's Cradle," channeling some of the horror he witnessed in Dresden to write about the dropping of the atomic bomb. (Some users may experience a paywall.)

How big is a supernova explosion?

Supernovas are the biggest explosions in the universe, often obliterating the area surrounding them. So what would happen if one exploded near Earth? If the sun went supernova it'd be like getting hit by a nuclear explosion every second for weeks. Of course, that's not happening anytime soon. This animated video shows how distance is the key factor, and how you shouldn't be worried.

Neutron stars, the remains of some massive stars after they explode in a supernova, are the densest directly observable objects in the universe.

Bomb cyclones can produce heavy rain, blizzard conditions, and intense winds

Known as "bombogenesis" in meteorology, these systems get their colloquial name from their rapid intensification over a 24-hour period—a phenomenon seen in some tropical cyclones. They occur most commonly along the coasts of the Northeast and Northwest US when there is a severe temperature difference between colliding air masses.

Hubble's average used power is less than half the power generated by its solar arrays

The space telescope's components use about 2,100 watts, or about as much power as five refrigerators. When exposed to sunlight, the solar arrays can generate over 5,200 watts for the observatory, which was engineered by a team that included Judith Love Cohen, mother of actor Jack Black.

The US Navy used The 'Harvard Calculator' to solve advanced physics problems

Designed in 1937 by Harvard graduate student Howard H. Aiken, the IBM Mark I was a groundbreaking machine used to solve ballistic trajectories and other mathematical problems whose solutions were needed for the design of the atomic bomb in World War II. The device was one of the first mechanical computers.

Hydrogen vehicle adoption has struggled due to high costs and stiff EV competition

Despite features like fast refueling and zero emissions, hydrogen vehicles face significant hurdles in affordability and infrastructure. As of 2025, there are about 200,000 electric vehicle charging stations compared to fewer than 100 hydrogen fuel ones.

While atoms are normally made of protons, neutrons, and electrons, exotic ones have been built with antimatter—alternate versions of normal matter that live for fractions of a second and are about a billion times as rare.

Supercollider particles lag behind light by just 10 feet after 14 minutes of travel

The circular shape of the Large Hadron Collider allows particles to be repeatedly accelerated and redirected via electromagnetic fields rather than building equivalent energy in a linear chamber hundreds of miles long. The latter would require 5 trillion D batteries to achieve equivalent near-light speeds.

How powerful was the volcanic blast that destroyed parts of ancient Rome?

This article details how strong Mt. Vesuvius' powerful 79 CE blast may have been. Pompeii lay a bit further from the volcano's slopes than Herculaneum, a smaller seaside city. While Pompeii was mainly destroyed by ash and lapilli—glassy fragments of lava ejected during volcanic eruptions—Herculaneum was first hit by a scorching pyroclastic cloud of volcanic gas and other matter.

Metallic hydrogen exists in Jupiter and Saturn due to high pressure and temperature

This state of hydrogen has metallic properties, including conductivity, which powers these planets' magnetic fields. First theorized in the 1930s, its existence was confirmed through indirect evidence before being created in a Harvard lab in 2017.

Fireworks make a loud booming sound after exploding due to air expanding faster than the speed of sound.

Sunflowers have long been a symbol of nuclear disarmament because they can extract large amounts of radioactive cesium from soil.

The United States is one of only around two dozen countries with a fully federal system of government, in which power is divided between national and state governments.

The United States has had a tumultuous relationship with Cuba since its 1959 revolution, highlighted by a nuclear crisis and a decades-long trade embargo.

For centuries, Niagara Falls has been a magnet for daredevils seeking to conquer one of nature's most powerful wonders, with its 200-foot drop and water rushing at 32 feet per second with 280 tons of force.

View the ten deadliest tornadoes in US history.

Experimental hantavirus vaccines and therapies, still under development, have long been funded by the US military.

The history of many kitchen appliances involves unexpected discoveries and applications, including wartime radar turned hamster defroster and replacing an 'ice king' with heat-stealing boxes.

The first image of a black hole was captured by creating an Earth-sized virtual observatory from a network of eight radio telescopes.

Iran's Revolutionary Guard Corps is independent of Iran's regular army and is one of the most powerful and influential military-political organizations in the Middle East.

The boiling temperature of water decreases with increasing elevation because the molecules need less energy to overcome the lower atmospheric pressure associated with thinner air.

After her fellow cult members tried to kill her with an LSD-infused hamburger, one member of the Manson Family, the murderous cult led by Charles Manson, decided to testify against the group's leader.

The syncytiotrophoblast is the outer layer of the placenta and the largest human cell, spanning an area about twice that of a king-sized bedsheet.

US housing costs have risen by roughly 175% between 1991 and 2026—but a growing number of Gen Zers are becoming homeowners anyway. In 2025, 4% of homebuyers were Gen Z, up from 3% the year before.

Sony set the standard for cylinder-shaped batteries when it repurposed manufacturing equipment used to make rolls of magnetic recording tape.

Hedge funds, the private investment firms that trade a wide swath of financial assets, make money by imposing steep fees on investors and from the fund's investment performance.

In 1963, a basement renovation in Turkey revealed a passageway to a hidden, multilevel underground city that once housed as many as 20,000 people

Before writing 'Walden,' transcendentalist Henry David Thoreau nearly burned down his hometown with a campfire that grew out of control.

Visualize how CRISPR-Cas9—a type of immune system used by single-celled organisms to attack invasive viruses—targets and makes precise changes to a gene's DNA.

Browse a detailed visual analysis of over 200,000 similes—comparisons that often use 'like' or 'as'—from popular fiction to see how frequently writers the same idiomatic expressions.

Budweiser stores yeast derived from the original 1800s strain in a secret bunker, which only the Head of Yeast Management can access—not even the CEO