Asteroid Apophis Is On Its Way to a Close Encounter with Earth

In the vastness of space, where celestial bodies dance to the gravitational tunes of the universe, one performer has caught the attention of humanity.

Apophis, a 340-meter-wide asteroid, is set to make a historic close approach to Earth in 2029.

This isn’t just any flyby; it’s a cosmic event with scientists and skywatchers buzzing with anticipation. But why all the fuss about a space rock?

Apophis: From Obscurity to Infamy

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Image Credit: Dima Zel/Shutterstock.

Unveiled in 2004 and initially known as 2004 MN4, Apophis ¹ quickly shifted from a mere blip in the cosmos to a notorious space rock when initial calculations gave it a 3% chance of striking Earth in 2029. This alarming probability thrust Apophis into the spotlight, warranting its name after the Egyptian deity of chaos.

Such a high-impact risk was a rare and unsettling discovery. However, by March 2021 ², NASA’s refined observations brought collective relief, confirming that Apophis poses no collision threat for at least the next century.

This celestial close call, once a harbinger of potential doom, now promises an extraordinary opportunity for scientific study as it whizzes past Earth closer than any large asteroid in recorded history.

Why Ground Observations Aren’t Enough

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Image Credit: BearFotos/Shutterstock

While ground-based telescopes and radar systems provide valuable data, sending a spacecraft to Apophis is crucial due to the Yarkovsky effect, a subtle force from the asteroid’s absorption and re-emission of solar radiation causing a slight but significant push.

Recent studies, including 2021 observations, confirm a non-zero Yarkovsky acceleration ³ for Apophis, making precise predictions of its trajectory and future close approaches essential.

This effect, Apophis’s leading source of orbital uncertainty, can only be accurately measured and understood through up-close observation, underscoring the need for spacecraft missions to study its impact on the asteroid’s path directly.

NASA’s Osiris-Apex Mission

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Image Credit: L Galbraith/ShutterStock.

The OSIRIS-Apex mission ⁴, evolving from OSIRIS-Rex, will embark on an 18-month investigative journey with Apophis, leveraging Earth’s gravity for a post-2029 encounter rendezvous. It aims to deepen our understanding of “stony” (S-complex) asteroids by providing high-resolution data and challenging our knowledge of these celestial bodies.

Fifteen months into orbiting Apophis, APEX will employ its thrusters to disturb the surface, revealing subsurface materials and offering insights into space weathering and surface strength.

This mission is pivotal not just for scientific discovery but also for planetary defense, as understanding Apophis’s structure and properties is crucial for developing mitigation strategies for potentially hazardous asteroids.

The Future of Apophis & Earth

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Photo Credit: sdecoret/Deposit Photos.

While the immediate threat of an Apophis impact has been ruled out for the next century, the slight chance of a future collision remains.

Understanding the Yarkovsky effect and Apophis’s exact path is vital for predicting and, if necessary, preventing such an event. Missions like Osiris-Apex and future endeavors are not just scientific pursuits but part of our planetary defense strategy.

As we await the 2029 encounter with bated breath, remember that sometimes, the universe offers not just beauty but also lessons in survival.


Martha A. Lavallie
Martha A. Lavallie
Author & Editor | + posts

Martha is a journalist with close to a decade of experience in uncovering and reporting on the most compelling stories of our time. Passionate about staying ahead of the curve, she specializes in shedding light on trending topics and captivating global narratives. Her insightful articles have garnered acclaim, making her a trusted voice in today's dynamic media landscape.