and Carnegie believed that great discoveries demanded the worlds bigge — Bob Berman

"Originally, the seven star categories were labeled A, B, and so on, according to how much hydrogen emission was in their light. But the sequence soon got reshuffled according to the stars . For more than a century now, astronomers everywhere have known these —as intimately as s know their fundamental seasonings or s the . The letters are a continuum from the bluest, hottest, most massive stars (types O and B) to the reddest, coolest ones (type M). In between are creamy white, moderate stars of type G (like the Sun) and yellow or orange type K. There are no green stars in the universe."

"Slowed and cooled by the thick , s no longer incandesce as they approach the surface and are barely warm when they land. On August 31, 1991, one smashed into a lawn next to two boys in , who immediately picked it up and later described it as slightly warm to the touch. In fact, meteors are not hot enough to glow once theyve dipped below fifty s in altitude, having decelerated dramatically from their original fierce speed of twelve to forty-five miles per second down to anywhere from a twentieth to half a mile per second. But thats still fast enough to cause trouble. s "Risk" issue (May 1996) presented statistical evidence that were each six times more likely to die from a than in an . The reason: The post-impact effects of a meteor a few miles wide can wipe out most or all of the human race, while relatively few of us will ever be crash victims."

"Just a century ago, the of science, and even common sense, held that all objects, including atoms and photons, have an existence independent of our of them. But thats been replaced by a more modern view—that our observation itself is necessary for the very existence of photons and electrons, a . But does an electrons collapse and turn into an actual particle if a cat is watching? Would light always be waves and never discrete photons if no humans were around? Our best answers are "Who knows?" and "Yes" respectively, but obviously this whole business is -strange."