Saturday, January 12, 2013

Let Us Ponder Stars

Few of us have the time or inclination to ponder the nature of stars, where they form and how they come to be, which if nothing else reflects an impoverished curiosity about our own atomic genealogy. Every atom in our bodies, every atom shaping an unforgettable face or reddening an infected hangnail, every atom of every thread of DNA in each of the 100 trillion cells we trundle about each day—every one of those atoms save hydrogen was exhaled at some earlier point in the history of the universe by an exploding star. And if that ancestry fails to move us, we might at least remember that our fragile and privileged ecological niche in an extremely vast and inhospitably frigid cosmos depends on the proximity of one particular star, the sun, which is gentle enough to warm an orchid yet variable enough to touch off ice ages, distant enough to spare us the roar and force of its inferno, dependable enough that we can set our circadian clocks against it and get up each day to ponder such mysteries as the origin of stars. Stars do not just happen. They result from complex astrophysical processes; they are milky accretions of dust and gas that ignite into luminous beacons of light, light conceived in a manner as mysterious and miraculous as the birth of a pearl, and the evolution of these cosmological jewels occurs only in special birthing places, and only under the right conditions. Any effort to identify those birthing grounds, often referred to as “stellar nurseries,” sends astronomers down a path of celestial cartography, and it is a path that has been traveled with singular success by radio astronomy in the post-World War II era.
   [Stephen S. Hall, Mapping the Next Millennium, Vintage, 1993, p. 308]

This paragraph is part of an introduction to a chapter in Hall’s book on mapping stellar nebulae—rather than on the subject of how elements came into existence. Hence it does not get into the greater mysteries of that subject, among them that, in order even to have genealogies ourselves, three different stars had to come into being. Of those the first two had to have lived out their lives and sent their products into space—there to form stars or planets. And the third sun gives us life. An earlier post on that subject, “Bodies Made of Diamonds” (link) provides a summary.

No comments:

Post a Comment