'God of Chaos' asteroid could be pushed into a collision course with Earth
The path and odds of asteroid 99942 Apophis striking Earth are higher than we previously thought. This is the conclusion of astrophysicist Paul Wiegert.
It was back in 2004 when astronomers first observed an asteroid that received a notorious title – Apophis.
Apophis on the impact hazard scale
The asteroid grabbed attention, not for its name that resonates with an ancient Egyptian ‘god of chaos,’ but due to its high placement on the Torino impact hazard scale.
Upon assessing its size and trajectory, researchers rated Apophis as a 4, making it the highest-rated asteroid yet.
But, this rating was still low enough to discard the possibility of Apophis striking Earth. Labeled “one to watch,” Apophis is set for close encounters with our planet in 2029, 2036, and 2068.
History of Earth’s asteroid collisions
Earth’s history has seen its fair share of asteroid collisions, which have really shaped its surface and influenced the evolution of life.
Scientists think one of the biggest impacts happened about 66 million years ago when a massive asteroid hit the Yucatán Peninsula in Mexico.
This event, known as the Chicxulub impact, was key to the mass extinction of the dinosaurs.
The collision unleashed a huge amount of energy, causing wildfires, tsunamis, and a “nuclear winter” effect that drastically changed the planet’s climate.
Throughout history, smaller asteroid strikes have also made their mark. Take the Tunguska event in 1908, for instance; it flattened over 800 square miles of forest in Siberia, likely from an asteroid or comet exploding in the atmosphere.
More recently, in 2013, a meteor blew up over Chelyabinsk, Russia, injuring people and damaging buildings.
Exploring the odds of a collision course
In a recently published study in The Planetary Science Journal, Wiegert, from the University of Western Ontario, explores a new dimension of odds — the chance of a smaller object striking Apophis and altering its course to an Earth-collision path.
Pondering over the odds might seem like an exercise in gloom, but in the realm of astrophysics, every possibility demands serious contemplation.
To investigate the chances of Apophis being pushed into Earth’s path, Wiegert began by considering that objects moving at varying speeds and of different sizes result in different courses.
The results of his study suggest that an object as small as 0.6 meters across could potentially nudge the asteroid onto a collision trajectory post-2029.
Astonishingly, an object just 3.4 meters across could strike with enough force to set Apophis on an Earth-collision path by 2029.
Assessing the impact risk
The complex nature of assessing and predicting the risk of celestial impacts involves more than merely calculating probabilities.
The work of researchers like Wiegert provides invaluable insights into the mechanics of potential disasters, where even the minutest variables can tip the scales in unforeseen directions.
Through the use of advanced simulation techniques and observation technologies, scientists can predict with greater accuracy the interactions between cosmic objects like Apophis and their potential paths.
This knowledge not only advances our understanding but also underscores the importance of preparedness, offering humanity an opportunity to develop possible mitigation strategies well ahead of time.
Monitoring Apophis and other asteroids
Technological advances have revolutionized our capability to monitor asteroids like Apophis. High-resolution telescopes and sophisticated space missions deliver real-time data, empowering astronomers to track the positions and velocities of asteroids with unprecedented precision.
The development of systems such as the Near-Earth Object Observations program and proposed initiatives like the space-based infrared telescope further enrich our toolbox for managing cosmic threats.
With these technologies, the scientific community aims to not only enhance the precision of impact predictions but also enable prompt response strategies, ensuring that potential threats are effectively neutralized before any encounter with Earth.
Probability of an encounter with Apophis
After establishing the size of objects that could potentially change the course of Adophis, Wiegert set out to estimate the number of objects that could cause such a catastrophic change.
For this, he utilized the yearly count of 3.4 meter-sized objects striking Earth as a reasonable guide. Using this reference, he calculated the odds of such an object striking Apophis.
Wiegert found that the probability of an impact that could significantly displace Apophis (compared to its miss distance in 2029) is less than one in 109, which is quite low.
Yet, we must remember that a collision, no matter how powerful, must strike at just the right angle to propel Apophis towards Earth.
Weigert suggests that the odds of a perfect hit are around 1 in 2 billion. And the likelihood of such an impact resulting in a later catastrophe? That stands at 1 in 1 million.
As humans, we’re notoriously bad at interpreting probabilities, but this is not just about playing with cosmic odds. It’s about understanding the unpredictable nature of our universe and staying prepared. After all, as the saying goes, “forewarned is forearmed.”
The study is published in The Planetary Science Journal.