New Delhi: The Indian Space Research Organisation ( ISRO ) is closely monitoring a large asteroid named Apophis, which is expected to have its closest encounter with Earth on April 13, 2029. Named after the Egyptian God of Chaos, Apophis is hurtling towards Earth and has drawn attention due to its potential threat.

In response to the growing risks posed by extra-terrestrial objects, ISRO has added a new domain, planetary defense, to its portfolio. This initiative is aimed at safeguarding Earth from such objects.

"A large asteroid strike is a real existential threat for humanity. ISRO is very alive to that threat, and our Network for Space Objects Tracking and Analysis (NETRA) is monitoring Apophis very closely. After all, we have only one Earth to live on. India will cooperate with all nations to ward off this and other such future threats," said Dr. S Somanath, Chairman of ISRO to a leading english daily. 

Apophis was first discovered in 2004, and its periodic approach to Earth has been tracked carefully since then. The next encounter is expected in 2029, followed by another in 2036. Although concerns about its potential impact with Earth persist, some studies suggest that the 2029 encounter will likely result in a flyby, rather than a collision.

The proximity of this encounter is notable, as Apophis is expected to come closer to Earth than India’s geostationary satellites, which orbit at about 32,000 kilometers above the planet. No other asteroid of its size has ever approached Earth this closely.

Continental Scale Devastation

Apophis is larger than India’s largest aircraft carrier, INS Vikramaditya, and the Narendra Modi Stadium in Ahmedabad. The asteroid's diameter is estimated to be between 340 and 450 meters. According to ISRO , any planetary body with a diameter larger than 140 meters and passing close to Earth is considered potentially hazardous. An asteroid of this size could cause "continental scale devastation," with estimates suggesting that if an asteroid larger than 10 kilometers in diameter struck Earth, it could lead to "mass extinction."

Dr. A K Anil Kumar, head of ISRO 's NETRA division, emphasized the potential for disaster. "If it collides with Earth, it can cause a catastrophe. It can cause local extinction. The dust thrown up by the collision can blanket the atmosphere, causing global disruption," he explained.

Historical records show that a meteor hit India around 500,000 years ago, creating Lonar Crater Lake in Maharashtra , which spans over a square kilometer. Reflecting on this, Dr. Somanath remarked, " ISRO will surely study the Apophis asteroid on its closest approach in 2029. After all, we have a living example of the Lonar Crater Lake made by a meteor strike in Maharashtra."

NASA Plans Mission to Avert Crisis

The world's leading space agencies, including NASA, are preparing several missions to study Apophis' trajectory and composition. NASA’s OSIRIS-REx spacecraft, which successfully returned samples from another asteroid, is now being redirected to rendezvous with Apophis. The European Space Agency is also considering launching the Rapid Apophis Mission for Security and Safety (RAMSES) in 2028, with India possibly joining this mission.

Various methods to prevent an asteroid impact are under consideration, ranging from spacecraft impacts like NASA’s Double Asteroid Redirection Test (DART) to more passive methods such as using a gravity tractor or a high-speed ion beam to change the asteroid’s course. As a last resort, nuclear explosives could be used to detonate on the asteroid.

Past Asteroid Threats

While Apophis is being watched closely, it is not the first asteroid to pose a threat to Earth. In recent history, a 20-meter diameter asteroid struck Oblast, Russia, on February 5, 2013, injuring about 1,500 people and damaging 7,200 buildings. Another significant event occurred in 1908 when a 30-meter asteroid hit Tunguska, Russia, destroying approximately 80 million trees.

The most devastating asteroid impact is believed to have occurred 650 million years ago, when a 10-15 kilometer diameter asteroid struck Mexico, leading to the extinction of dinosaurs and wiping out nearly 70% of all species on Earth.