NASA's radar signals a warning, alerting scientists that a world-destroying asteroid has been discovered and could collide with Earth in 10 years.
Governments around the world are quickly informed of the potential disaster, allowing them time to create a plan to notify the public.
One year before impact, global space agencies launch nuclear deflection missiles in hopes of diverting the massive asteroid, but the mission ends in failure.
With months to go, FEMA orders evacuations from the impact zone, and as the final hours tick away, the public is warned to prepare for the worst.
While NASA has said such a scenario is unlikely in the near future, an asteroid did hit Earth recently, with scientists detecting it only eight hours before it entered our atmosphere.
Auto Draft The small space rock, which passed over the Philippines, was just three feet in size, too small to trigger major alarms.
A 2021 White House report recommended that if an asteroid at least 165 feet wide is detected and could strike Earth within 50 years, a reconnaissance mission should be carried out.
The report noted that a 3,300-foot-wide asteroid could cause a "global catastrophe," a three-mile-wide object would be "above the global catastrophe threshold," and a six-mile-wide asteroid could result in a "mass extinction."
However, an exercise conducted by NASA, FEMA, and the United Nations in April showed that if such a world-ending asteroid were discovered, at least 14 years of preparation would be needed.
Detecting The World-Destroying Asteroid - 10 Years Out
NASA's ground-based telescopes spot the massive asteroid and cross-check it with other space rocks in their database to confirm it's a new discovery.
The space agency uses several sky-scanning projects, including the Catalina Sky Survey, which recently detected the asteroid that passed by on Thursday.
Other early-warning systems like NEOWISE (Near-Earth Object Wide-field Infrared Survey Explorer) also assist in identifying potential threats. NEOWISE is a spacecraft with a 20-inch infrared telescope that operates in two wavelength ranges, scanning the skies for near-Earth objects.
Once an object is spotted, astronomers analyze its brightness and movement to ensure it's not already documented. The discovery is then reported to the Minor Planet Center (MPC), the global hub for tracking asteroids, minor planets, and comets.
Together, the MPC and NASA calculate the asteroid's orbit to predict whether it poses a danger to Earth.
After studying the space rock, the team concludes that it could pass within five million miles of our planet and issues warnings to space agencies worldwide, according to NASA.
With the world now aware of the looming threat, space agencies from around the globe collaborate to develop a plan to deflect the asteroid, beginning about two years after its detection.
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Auto Draft Launching An Asteroid Deflection - Two To Five Years Before Impact
In 2022, NASA tested a method called the Double Asteroid Redirection Test (DART), in which a spacecraft crashed into an asteroid at 14,000 miles per hour, creating a huge cloud of dust and debris and successfully changing its course.
While that particular asteroid wasn't a threat to Earth, NASA could use this technique to deflect an asteroid that poses a world-ending risk.
However, earlier this year, NASA's planetary defense chief cautioned that a DART-style mission wouldn't be possible if we had less than five years before impact.
As humanity prepares for its ultimate defense mission, NASA and international partners are exploring different strategies, including using spacecraft and nuclear weapons.
After about five years of planning and testing, the decision is made to use nuclear bombs to target the asteroid.
Then, with two years remaining before impact, teams launch explosives and a detonator to set off at a short distance from the asteroid.
Kaliat Ramesh, a professor of mechanical engineering and materials science at Johns Hopkins University, shared with VOX: "We would estimate that it would take energy equivalent to about 200 gigatons of TNT to fully disrupt an asteroid with a 12-mile diameter."
One gigaton equals one billion tons of TNT, meaning it would take 10 million Hiroshima-sized bombs to destroy the massive asteroid on a collision course with Earth.
The only rockets capable of carrying such a large nuclear payload would likely be NASA's Space Launch System (SLS) and Elon Musk's SpaceX Starship, though neither has been tested for this kind of mission.
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Auto Draft The nuclear approach would provide a quicker solution, a concept that might sound familiar to fans of the 1998 movie Armageddon, starring Bruce Willis and Ben Affleck.
In the film, NASA recruits a team of deep-sea drillers to destroy an asteroid headed for Earth and save the planet with only 18 days' notice.
Evacuation Plan - Months To Hours Before Impact
In the months leading up to the asteroid impact, global organizations like the Planetary Defense Coordination Office (PDCO) would develop detailed impact scenarios, estimating the destruction area, atmospheric effects, and potential worldwide consequences.
Accurate predictions of the asteroid's exact impact location would only become available as it gets closer and comes into radar range. Advances in deep-space radar could speed up this process.
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Auto Draft The data gathered by these organizations would be shared with FEMA and other emergency services, allowing them to warn people in the impact zone and begin mass evacuations months before the asteroid hits Earth.
Rescue plans would also be put in place, and relief teams would be prepared to respond immediately after impact to save as many lives as possible.
A 2023 NASA report estimated that anyone within 300 miles of the impact site, roughly 150 million people, "would need to either evacuate or find an appropriate shelter or build one."
As the final hours approach, the public would be instructed to stay indoors and receive continuous updates and guidance from authorities.
After Impact
The asteroid impact would result in catastrophic destruction, triggering tsunamis that wipe out coastal areas, along with powerful shockwaves and earthquakes.
Electrical grids and communication networks worldwide would fail almost immediately.
A huge dust cloud from the impact would block out the sun, leading to a drastic drop in temperatures and a "nuclear winter" that could last for decades.
Earth would be plunged into darkness as massive fires burn, depleting oxygen levels in the atmosphere.
Billions would lose their lives, and the survivors would face starvation, freezing conditions, and the complete collapse of civilization's infrastructure.
