Simulation Shows Earth’s Devastating Collapse If Oxygen Vanished for Just 5 Seconds

It might sound harmless—just five seconds without oxygen—but a simulation has revealed that even this brief disappearance would lead to catastrophic consequences for our planet.

While oxygen only makes up about 21% of Earth’s atmosphere (compared to 78% nitrogen), it plays a vital role in supporting life and maintaining the planet’s structural integrity.

You might think five seconds without oxygen wouldn’t matter much—after all, most people can hold their breath longer than that. But according to a popular video by the What If YouTube channel, that couldn’t be further from the truth.

Instant Collapse

In the simulation, the narrator explains that although your breathing wouldn’t be immediately affected, nearly everything else would be.

Since oxygen is essential in binding concrete, any structure made from it would instantly weaken and possibly collapse.

Metal Fuses Together

Normally, a thin layer of oxidation prevents metal surfaces from welding together. Without oxygen, this layer disappears, causing untreated metal to instantly fuse.

Say Goodbye to the Ozone Layer

The ozone layer, which shields us from the sun’s harmful UV rays, is formed from oxygen. Without it, people exposed to sunlight would suffer immediate and severe sunburns.

The simulation adds: “On top of the sunburn, your inner ears would rupture. Losing 21% of atmospheric pressure is like being dropped 2,000 meters below sea level in an instant—our ears wouldn’t have time to adjust.”

Planes Fall From the Sky

Without oxygen, fire can't exist. All non-electric engines would shut down, meaning millions of vehicles would stall. More dramatically, planes would lose power and plummet from the sky.

Even Earth’s crust—which is made up of about 45% oxygen—would begin to disintegrate.

A World in Darkness

The skies would go completely dark. Normally, oxygen molecules help scatter sunlight, which gives us a blue sky. Without oxygen, light wouldn’t scatter, and Earth would be plunged into darkness.

“Oddly Undramatic”

Process engineer Geoffrey Widdinson gave his take on the scenario, saying, “When it comes to breathing, we probably wouldn’t notice much. Our bodies don’t sense low oxygen directly—only rising carbon dioxide levels. So unless CO₂ built up quickly, we wouldn’t feel like we’re suffocating.”

He continued: “It would actually be kind of undramatic. Sure, the sudden stalling of a hundred million cars would get attention, and instruments would detect the drop in air pressure—but we’d probably never figure out what really happened.”

Fortunately, this nightmare scenario is purely theoretical—and incredibly unlikely to ever happen.