In the months before the big quake, a series of smaller tremors jostled central Italy. (discovermagazine.com)
Just as a shaky camera results in blurry photographs, even small tremors will interfere with the telescope's image quality. (webbtelescope.org)
Engineers in China blame dams for at least 19 earthquakes over the past five decades, ranging from small tremors to one near Guangdong province's Xinfengjiang Dam in 1962 that registered magnitude 6.1 on the Richter scale — severe enough to topple houses. (scientificamerican.com)