16 years of Chelyabinsk meteor strike: A look back at the threat no one saw coming

Sixteen years ago, a small meteor struck the Earth's atmosphere in the quiet morning of February 15, 2013, over the city of Chelyabinsk in Russia. The space rock, which measured about 19 meters across, exploded with a loud boom and released energy greater than even an atomic bomb. As the world celebrates another anniversary of the terrifying spectacle, let us take a look back at what transpired and what scientists have done to avoid another such event. 

How powerful was the meteor strike?

The meteor struck the Earth at a speed of about 17 kilometers per second and exploded roughly 22 kilometers above the surface. The explosion is estimated to have released energy equivalent to 4,40,000 tons of TNT which led to the shockwaves damaging buildings up to 320 square kilometers in the region. For comparison, the atomic bombs dropped in Japan's Hiroshima and Nagasaki during the second World War had energy quivalent to 16,000 tonnes and 21,000 tonnes of TNT, respectively. 

(Damaged building after the Chelyabinsk meteor strike: Image: AP)

(The incoming meteor briefly burned brighter than the sun; Image: AP)

Experts say that the Chelyabinsk meteor briefly glowed 30 times brighter than the sun during its atmospheric entry and the damage to buildings caused injuries to over 1,600 people. NASA's Planetary Defense Officer Lindley Johnson had called it a 'cosmic wake-up call' as it drew widespread attention to the development of planetary defence techniques and prevent such catastrophes. 

How have scientists dealt with the blow?

The incident in Russia resulted in the birth of the United Nations-backed International Asteroid Warning Network (IAWN) for detection and tracking of hazardous asteroids and also the establishment of the Space Missions Planning Advisory Group (SMPAG) offering a common ground to space agencies to collaborate on plans for preventing any possible asteroid impact. NASA also doubled down on developing its Near Earth Object (NEO) Observations Program whose aim is finding asteroids 460 feet (140 meters) and larger that represent the most severe impact risks to Earth. 

NASA says that it plans to identify 90% of hazardous asteroids early enough to allow deflection or other preparations to mitigate the impact. The European Space Agency (ESA) also has a Planetary Defence Office which works to ensure space safety and security activities and keeps an eye on near-Earth objects which can be a threat to Earth. On November 24, 2021, NASA launched its Double Asteroid Redirection Test (DART) mission with an intention to test a planetary defence technique. Under this mission, the DART spacecraft rammed into an asteroid named Dimorphos and managed to change its orbit by about 30 minutes. 

The success of DART gave scientists hope that an asteroid's path can be artificially tweaked and this project on a larger scale can save Earth from a planet-killing asteroid. The agencies have also made giant strides in the early detection of asteroids, which helped in issuing an early warning to the local population. There have been a couple of instances that were reported recently; the first being a tiny asteroid breaking up over France (it was detected 7 hours earlier) and the other is predicted to safely pass from a distance of about 46 lakh kilometers from Earth tonight.