🌅 The Closest Large Asteroid Flyby on Record

SOURCE

Eclipse Atlas

WHAT TO KNOW

• The asteroid Apophis will be clearly visible with the naked eye to around 90% of the world’s population during its ultraclose flyby on April 13, 2029, providing what astronomers say will be a “once-in-a-millennium” event for approximately 7.6 billion people throughout Australia, Asia, Africa, Europe, and South America (North America is the only continent that will not get a clear view of Apophis). The asteroid will be visible for seven hours as it zooms past Earth, coming within about 20,000 miles (32,000 kilometers) of the planet at its closest point, well within the altitude of several hundred satellites stationed in geosynchronous orbit. Experts say this is the first time in recorded history an asteroid of this size will come so close to Earth, and the first time humans have been able to predict a flyby of an asteroid visible to the naked eye. Watch an animation of the flyby.

WHY IT MATTERS

• Apophis is a peanut-shaped asteroid that spans around 1,500 feet at its widest point, meaning it’s about as wide as the Empire State Building is tall. An asteroid of that size is considered a “city killer,” as an impact would inflict significant damage on Earth. Thankfully, astronomers say there’s zero chance Apophis will hit the Earth in 2029 or within the next 100 years. A trio of missions coordinated by NASA, the European Space Agency, and the Japan Aerospace Exploration Agency will send satellites to observe Apophis during the flyby, with various institutions and observatories also making observations from the ground. The event is so significant that the U.N. has declared 2029 the International Year of Asteroid Awareness and Planetary Defence.

CONNECT THE DOTS

• Apophis is one of the 40,000 near-Earth asteroids astronomers have catalogued, including about 10,000 that have been discovered since 2023. Experts estimate astronomers have found 90% of the estimated 1,000 near-Earth asteroids greater than 1 kilometer in diameter—which would cause global damage in the event of an impact—but only around 30% of smaller asteroids that would also cause serious local or regional damage (like Apophis). Thankfully, most near-Earth asteroids will never come close to impacting the planet.