00317nam a2200109 a 450000500170000002000150001708200180003210000200005024500610007026000480013130000280017920251203110046.0  a0716750759  a523.1135bKAL  aKaler, James B.  aCosmic cloudsbBirth, death, and recycling in the galaxy  aNew YorkbScientific American Libraryc1997  axii, 252p.c24 cm. H.B.