... The choice of which type of electricity is called "positive" and which "negative" was made around 1750 by Ben Franklin, early American scientist and man of many talents (the stamp on the left commemorates his role as first US postmaster--and colonial postmaster before that). ... Franklin knew of two types of electric charge, depending on the material one rubbed. ... Later, when electric batteries were discovered, scientists naturally assigned the direction of the flow of current to be from (+) to (-...
... CURRENT ASPECTS OF REMOTE SENSING OF EARTH FROM SPACE . ... For developing of the scientific concept and the programs of global monitoring of the Earth from space and pursuant to the disposal of Presidium of Russian Academy of Sciences # 10310-717 (August 11, 2004 ) Space Research Institute RAS and Center of Space Observations of the Russian Space Agency during November 16-18, 2004 conduct the Second Opened All-Russia conference ' Current Aspects of Remote ...
... NASA's Hubble Space Telescope has detected a long-sought population of comets dwelling at the icy fringe of the solar system . The observation, which is the astronomical equivalent to finding the proverbial needle-in-a-haystack, bolsters proof for a primordial comet reservoir just beyond Neptune , currently the farthest planet from the Sun . ... The comet-disk lies just beyond Neptune and might stretch 500 times farther from the Sun than Earth . ... Comet Introduction Kuiper Belt Objects . ...