Word: nasa
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Dates: during 2000-2009
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...nuclear weapons into orbit, the treaty also requires space-faring nations to avoid "harmful contamination" of other worlds while exploring the solar system. Human beings have yet to set foot on other planets, so the risk today comes from bacteria that can hitch a ride on unmanned spacecraft like NASA's Mars Phoenix Lander, which arrived on the red planet's surface last May. (See pictures of the Mars Rover's five years in space...
That's why NASA planetary scientist Christopher McKay, in an article in this week's Science, suggests the need for a stronger policy that ensures all exploration of Mars be "biologically reversible" - meaning we would be required to effectively wipe away our footprints and remove any possibility of contamination, by leaving behind nothing that could foster alien microbial growth. Such a policy would be especially necessary if we discover that life on Mars has emerged independently of life on Earth - what McKay calls a "second genesis" - as opposed to Martian life that arose through the exchange of meteorites between Mars...
Meanwhile the science on climate change grows more dire. James Hansen, NASA's climate expert, reported in a recent paper that the world needed to stabilize carbon in the atmosphere at 350 parts per million (ppm) to avoid the worst effects of warming - a more stringent goal than earlier estimates, which had a target of 450 ppm. (The current concentration is 385 ppm and rising fast, up from a pre-industrial level of 280 ppm.) That would require action that is far more ambitious than currently seems possible - both in the U.S. and in the developing world, where the bulk...
...bill calls for over one hundred programs which Congress plans to enact. These include addressing problems as diverse as community block grants, upgrading the forestry service, bridge removal, and NASA research funding. The remarkable thing about the legislation is that almost every program is ill-defined and subject to broad interpretation and a wide variation as to how it might be enacted...
...used ModelE, designed by NASA's Goddard Institute for Space Studies, and one of the models used to produce the results of the Intergovernmental Panel on Climate Change (IPCC). The model does an excellent job of simulating climate change that resulted from volcanic eruptions in the past. That gave us confidence. What's more, a group repeated the calculations for the Pakistan-India scenario with a different model at the National Center for Atmospheric Research in Boulder, Colo., and the results almost exactly agreed. Their research showed how the smoke from the fires would open up holes in the ozone...