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Leif J. Robinson - Philip's Astronomy Encyclopedia

: Philip's Astronomy Encyclopedia
: Leif J. Robinson
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: 08.08.2008 17:17:06
: 296
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: The progress of astronomy or, more precisely, astrophysics over the past century, and particularly the past generation, is not easily pigeon-holed. On the one hand, profound truths have tumbled abundantly from the sky. Here are four diverse examples: 1. Our universe began some 14 billion years ago in a single cataclysmic event called the Big Bang. 2. Galaxies reside mainly in huge weblike ensembles. 3. Our neighbouring planets and their satellites come in a bewildering variety. 4. Earth itself is threatened (at least within politicians horizons) by impacts from mean-spirited asteroids or comets. On the other hand, ordinary citizens may well feel that astronomers are a confused lot and that they are farther away than ever from understanding how the universe is put together and how it works. For example, yesterday we were told the universe is expanding as a consequence of the Big Bang; today we are told it is accelerating due to some mysterious and possibly unrelated force. It doesnt help that the media dine exclusively on gee-whiz results, many of them contradictory and too often reported without historical context. I cant help but savour the pre-1960s era, before quasars and pulsars were discovered, when we naïvely envisioned a simple, orderly universe understandable in everyday terms.
: 27.56