Chelyabinsk meteor

The Chelyabinsk meteor (Russian: Челябинский метеорит, romanised: Chelyabinskiy meteorit) was a superbolide that entered Earth's atmosphere over the southern Ural region in Russia on 15 February 2013 at about 09:20 YEKT (03:20 UTC). It was caused by an approximately 18-meter (60 ft), 9,100-tonne (10,000-short-ton) near-Earth asteroid that entered the atmosphere at a shallow 18‐degree angle with a speed relative to Earth of about 19.2 km/s (68,980 km/h; 42,860 mph). The light from the meteor was briefly brighter than the Sun (which is about −26.7 magnitude), visible as far as 100 kilometers (62 miles) away. It was observed in a wide area of the region and in neighbouring republics. Some eyewitnesses also reported feeling intense heat from the fireball.

The object exploded in a meteor air burst over Chelyabinsk Oblast, at a height of about 30 kilometres (18.6 miles). The explosion generated a bright flash, producing a hot cloud of dust and gas that penetrated to 26 kilometres (16 mi), and many surviving small fragmentary meteorites. Most of the object's energy was absorbed by the atmosphere, creating a large shock wave. The asteroid had a total kinetic energy before atmospheric impact equivalent to the blast yield of 400–500 kilotonnes of TNT (1.7–2.1 petajoules), estimated from infrasound and seismic measurements. This was approximately 30 times as much energy as that released by the atomic bomb detonated at Hiroshima.