Word: hydrogenate
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...look for can practically see stars forming before his eyes. These star wombs are great clouds of gas and dust floating in interstellar space. Like the clouds that formed in the expanding primordial fireball shortly after the big bang, they consist mostly of nature's simplest molecule, hydrogen. A star is born when some force, perhaps a shock wave, drives enough of the hydrogen molecules in a cloud sufficiently close to one another that they are held together by their mutual gravity. As a result, a huge pocket of condensed gas, trillions of miles across, is formed...
...balls have reached the critical level of 20 million degrees F., hot enough to cause fusion−the awesome process that occurs in a detonating hydrogen bomb...
Long since stripped of their electrons by the high temperatures, the nuclei of the hydrogen atoms slam together at tremendous speeds, fusing to form helium and releasing huge amounts of energy. Though the nuclear fires have been lit, the actual ignition is hidden deep within the interstellar clouds. "Nature very discreetly pulls the curtain over the act of birth," says Thaddeus. But the infant star soon makes its presence known, shining through and illuminating the obscuring cloud. This process is occurring in the Orion Nebula (see color page), the illuminated portion of a gigantic cloud of gas and dust that...
...fusion of hydrogen to form helium marks the beginning of a long and stable period in the evolution of the star−a combination of adolescence and middle age that constitutes 99% of the lifespan of a sun-size star. During this period, the tremendous energy radiating from the star's center neutralizes its gravitational force, and the great glowing orb shrinks no further. But as it must to all stars, death eventually comes. How long a star lives depends on its mass. Generally, the more massive a star is, the shorter its life is. Stars with a mass...
...beginning of the end comes when the star has exhausted much of the hydrogen near its core and starts to burn the hydrogen in its outer layers. This process causes the star gradually to turn red and swell to 100 times its previous size, pouring out prodigious amounts of energy. Betelgeuse, in the constellation Orion, is such a "red giant," visible to the naked eye. When the sun undergoes a similar metamorphosis, it will envelop Mercury and Venus and vaporize the earth. By that time, 5 billion years from now, man's descendants may have found a new home...