scientific american - 2001 01 - brave new cosmos - a special report

... Scientific American January 2 001 A Cosmic Cartographer T his summer the National Aeronautics and Space Administration is plan- ning to launch a Delta 2 rocket carrying an 83 0- kilogram, four-meter-high spacecraft. ... Gravity That Repels • Galaxy-Size Particles Oh, yes. A SPECIAL REPORT A SPECIAL REPORT Copyright 2000 Scientific American, Inc. Scientific American...

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... Oceanic and Atmospheric Ad- ministration (NOAA). These records pro- vide average monthly sea-surface tem- perature and track anomalies derived from satellite data that are validated by measurements ... is part of nature or that it is what humans use to their advantage. If you take the practical ra- ther than the idealistic approach, you save a lot of headaches.ÓÑPaul Wallich 24 SCIENTIFIC...

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... lands of Cana- da, Alaska and Eurasia, in particular, may help moderate climatic change by serving as a sink for the greenhouse gas carbon dioxide. Wetlands also have commercial and utilitarian functions. ... interference. A sea- wall or a dike at the landward boundary of a salt marsh can prevent the inland migration of the marsh when the sea 68 SCIENTIFIC AMERICAN January 1994 BO...

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... forever. Flaws of Translation R egrettably, this approach is ßawed in two fundamental ways. First, re- lational databases are less standardized than they appear. Commercial relation- al database systems ... tables in a relational database can- not transparently show structure. That is, the database could not immediately make it clear that a corporation con- sisted of one headquarters, Þve...

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... April, Szostak and Charles Wil- son of the University of California at Santa Cruz revealed in Nature that they had made ribozymes capable of a broad class of catalytic reactions. The cataly- sis of ... lack of a ßat rate for lo- cal calls is limiting Internet develop- ment in Japan,Ó comments Naoki Ya- mamoto, editor of Digital Highway Re- port, a newsletter for Japanese infor- mation m...

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... 1996 Scientific American, Inc. T o the oohs and aahs of a handpicked audience and the whir of camera shutters, Gra- ham S. Hawkes gently tugs away a logo- emblazoned veil to reveal a new and truly ... and Analysis Scientific American January 1997 31 surface. Initially this molten rock had ascended comparatively slowly, allow- ing the volatile gases it contained to es- cape grad...

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... mutations are thought to accu- mulate at a constant rate, the amount of time that has passed since two mtDNA News and Analysis30 Scientific American January 1998 Bird Brains Some bird brains are bigger ... that’s all. I did it because I loved it.” Pour la gloire. —W. Wayt Gibbs in Paris News and Analysis40 Scientific American January 1998 A NAKED MAN: Lévi-Strauss among the Nambi...

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... for a broad- er appreciation of the factors lead- ing to such a calamity. That year, the amount of food available per capita was high in Bangladesh: in- deed, it was higher than in any oth- er ... per person that year was high. HUBERT LE CAMPION SYGMA Copyright 1998 Scientific American, Inc. News and Analysis Scientific American January 1999 21 T he Internet has dramatically altere...

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... both.” —Barbara Gallagher BARBARA GALLAGHER, a free- lance writer focusing on the space sci- ences, is a research associate at the In- stitute for Advanced Psychology in Tiburon, Calif. SCIENCE AND ... placental mammals may have originated in North America, not Asia. The 110-million-year-old jaw represents a placental named Montanalestes, which probably looked like a shrew (inset). FR...

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... in ice ages. Copyright 2 001 Scientific American, Inc. Scientific American February 2 001 33www.sciam.com A small start-up firm in Santa Clara, Calif., had a big idea five years ago. By adapting the ... UNIVERSITY OF CALIFORNIA AT SANTA BARBARA (bottom) MICROLASER LIGHT emits from a 1.31-micron VCSEL at Sandia National Laboratories (top); the University of California at Santa Ba...

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