Radiometric dating graph
Meteorites On February 15, 2013 a meteor exploded in the sky over Chelyabinsk, southern Russia.
Although no people or buildings were hit by the resulting meteorite, the shockwave from the exploding object injured about 1500 people and caused damage to 7200 buildings in the region.
The fireball and was caught on video, mainly by dash cameras throughout the region, which were posted on the internet by news organizations individuals.
Although the Chelyabinsk meteorite probably weighed about 12,000–13,000 metric tonnes, and measured 17 to 20 m in diameter before it exploded, sientists were quick to point out that it was very small compared to other objects that could potentially hit the earth.
Isotopes of a given element carry different numbers of neutrons, or neutrally charged particles, in their nuclei.
The sum of the number of neutrons and protons in an atom's nucleaus defines its approximate atomic weight.
The rules of play are not laws of nature, but arbitrarily agreed by the players, and sometimes changed during play.
There are many different kinds of radiometric dating and not all conclusions we will reach can be extrapolated to all methods used.
Also, different radiometric dating techniques independently converges with each other and with other dating techniques such as dendrochronology, layers in sediment, growth rings on corals, rhythmic layering of ice in glaciers, magnetostratigraphy, fission tracks and many other methods. There exists different versions, or isotopes of many elements.
The explosion released energy estimated at about 500 kilotons of TNT (about 20 to 30 times more energy than the Hiroshima atomic bomb).
The event brought to the world's attention the very real hazards associated with the impact of objects from outer space.