Objects closer to Earth than the L1 point are controlled by Earth's gravity. Objects beyond the L1 point are controlled by the Sun. When J002E3 came close to the L1 point in April 2002, the object passed throuhgh L1--like a portal--from a Sun-orbit to an Earth-orbit.
In the top 20km of the Earth's crust, the conditions are right to produce a nearly inexhaustible supply of hydrogen, said Prof Freund. Studies by the team of common rock types such as granite and olivine have revealed extraordinarily high levels of trapped hydrogen.
Therefore it has no half-life. Answer Hydrogen is an element that occurs in nature in three isotopes. Hydrogen-1, 1H, which is also called protium, accounts for about 99.985% of all hydrogen on Earth. Hydrogen-2, 2H, which is also called deuterium, is about 0.015% of the hydrogen on Earth.