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The Strategic Defense Initiative has been out of the news recently, but its scientific and political proponents still exist. Should the United States be thinking differently about defence in this era of glasnost ?
Real clouds may moderate global warming by negative feedback, or may work the other way. Comparison between observations and predictions suggests that clouds are cooling influences outside the tropics.
A new form of pure, solid carbon has been synthesized consisting of a somewhat disordered hexagonal close packing of soccer-ball-shaped C60 molecules. Infrared spectra and X-ray diffraction studies of the molecular packing confirm that the molecules have the anticipated 'fullerene' structure. Mass spectroscopy shows that the C70 molecule is present at levels of a few per cent. The solid-state and molecular properties of C60 and its possible role in interstellar space can now be studied in detail.