Meteorites & Asteroids / Asteroids & Comets

StudyBlue printing of Meteorites & Asteroids / Asteroids & Comets html, body, div, span, applet, object, iframe, h1, h2, h3, h4, h5, h6, p, blockquote, pre, a, abbr, acronym, address, big, cite, code, del, dfn, em, font, img, ins, kbd, q, s, samp, small, strike, strong, sub, sup, tt, var, b, u, i, center, fieldset, form, label, legend, table, caption, tbody, tfoot, thead, tr, th, td { margin: 0; padding: 0; border: 0; outline: 0; font-size: 100%; background: transparent; } body { line-height: 1; } blockquote, q { quotes: none; } blockquote:before, blockquote:after, q:before, q:after { content: ''; content: none; } /* remember to define focus styles! */ :focus { outline: 0; } /* remember to highlight inserts somehow! */ ins { text-decoration: none; } del { text-decoration: line-through; } /* tables still need 'cellspacing="0"' in the markup */ table { border-collapse: collapse; border-spacing: 0; } /* end RESET */ .header { min-width:800px; } .logo { padding:6px 20px 2px 20px; margin:0; 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Yet, not all large asteroids have been active The largest asteroids seen today may be nearly unbroken examples of original planetesimals but small asteroids are fragments produced by 4.6 billion years of collisions COMETS common misconception: comets do not whiz by across the sky like meteors. they are more like ships at sea, barely in motion PROPERTIES OF COMETS comets have two kinds of tails shaped by solar wind and radiation: gas (type I) and dust (type II) both released from the icy nucleus, coma comet dust doesn't just produce a comet tail, but also scatters across the SS, sometimes resulting as meteors comet nuclei are fragile and can break into pieces easily THE GEOLOGY OF COMET NUCLEI spectra of comet comae and tails indicate that the nuclei contain ices of water and other volatile compounds such as carbon dioxide, carbon monoxide, methane, ammonia, etc. (these materials would have condensed in cooler regions of the solar nebula)