Dust from outer space
نویسندگان
چکیده
منابع مشابه
Spam Zombies from Outer Space
How can better email worms be created? How can spyware claim more victims? How can better spam be sent? It turns out that these three questions are all related. We look at the future threat posed by email worms, spyware, and spammers that use zombie machines in a new way: sophisticated data mining of their victims' saved email. The end result skirts many defenses, and could trick even experienc...
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GDP growth is often measured poorly for countries and rarely measured at all for cities or subnational regions. We propose a readily available proxy: satellite data on lights at night. We develop a statistical framework that uses lights growth to augment existing income growth measures, under the assumption that measurement error in using observed light as an indicator of income is uncorrelated...
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متن کاملFrom Inner Earth to Outer Space
On a cold day in February 2001, a spacecraft landed on 433 Eros, an asteroid between the orbits of Mars and Jupiter. The spacecraft had completed its five-year journey to investigate fundamental questions about the nature and origin of near-Earth objects for the first time. The technical demands of the Near Earth Asteroid Rendezvous NEAR-Shoemaker (NEAR) mission were immense. A multidisciplinar...
متن کاملDust Measurements in the Outer Solar System
Dust measurements in the outer solar system are reviewed. Only the plasma wave instrument on board Voyagers 1 and 2 recorded impacts in the Edgeworth-Kuiper belt (EKB). Pioneers 10 and 11 measured a constant dust flux of 10micron-sized particles out to 20 AU. Dust detectors on board Ulysses and Galileo uniquely identified micron-sized interstellar grains passing through the planetary system. Im...
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ژورنال
عنوان ژورنال: Nature
سال: 1993
ISSN: 0028-0836,1476-4687
DOI: 10.1038/362415a0