Is Humanity at Risk of Extinction from an Approaching Asteroid?

A comet could potentially wipe out all life on Earth one day. Fortunately, planetary defense measures are being organized to protect us from such a catastrophic scenario. What strategies are being implemented?
A Celestial Threat to Earth
Can you envision a comet wiping out all life on Earth? “Ask the dinosaurs if an asteroid can obliterate life,” quips Jérémie Vaubaillon, an astronomer at the Paris Observatory. The recent discovery of asteroid 2024 YR4, measuring between 40 to 100 meters in diameter, has cast a shadow of concern among scientists.
When the Past Illuminates the Future
66 million years ago, a twelve-kilometer-wide asteroid struck Earth, leading to the extinction of the dinosaurs and 75% of terrestrial species. Today, with a more than 1% chance of hitting Earth on December 22, 2032, asteroid 2024 YR4 has become celestial enemy number one.
“A massive comet at least ten kilometers long, from the edges of the universe? It’s possible,” states the astronomer. Such a comet, spanning the length of Paris from north to south, could annihilate humanity, creating a massive crater, a tsunami, or plumes of black and red smoke.
Planetary Defense in Action
Fortunately, planetary defense efforts are underway. The International Asteroid Warning Network (IAWN), established under the auspices of the United Nations, monitors these celestial objects without undue alarm. Why? Because their trajectories still appear distant from Earth’s orbit.
In 2022, NASA attempted to alter an asteroid’s course named Dimorphos through a “kinetic impact” with the DART (Double Asteroid Redirection Test). Weeks later, NASA announced a positive outcome. Hera, a comet chaser, was launched in October 2024 to closely monitor Dimorphos’s movement.
“Planetary defense is inherently an international effort,” said Josef Aschbacher, Director-General of ESA. For astronomer Jérémie Vaubaillon, the goal is clear: “In celestial mechanics, it’s the speed that we need to change.” By slowing down the asteroid, its impact would be lessened.
Facing the Infinite
The prospect of such a cataclysm might seem daunting, but it reminds us of our earthly existence. “These scenarios bring us back to our condition as Earthlings, it’s quite dizzying to think about,” reflects the astronomer. Such perspectives undoubtedly remind us how fragile and precious our existence is.