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By looking at the relative numbers of neutrons of different energies scientists can determine what elements are in the lunar soil . Many countries want pieces returned that were taken many , even hundreds , of years ago , such as Greek statues and Native American artifacts . Researchers found that the hormone DHEA was ' an effective treatment for midlife-onset major and minor depression , ' leading to significant improvements on several measures of depression . Because the longer wavelengths require larger antennas for a given angular resolution , higher resolution microwave space sensors usually operate at the shorter wavelengths , with the exception of special applications . You can have multiple images open simultaneously in separate windows .