Planetary alignments (in astronomy called ‘conjunctions‘[4]) excite the public, and raise inevitable questions in their minds. Astronomers, especially those involved in public outreach programs, are used to answering these questions. However, when believers in various mystical systems use alignments as evidence for their own beliefs, many astronomers are at a loss to explain why the
Interpretation: When an earthquake occurs the seismogram will show ground motions that typically last from several tens of seconds to many minutes, depending on the size of the earthquake and the sensitivity of the seismograph. The height of the recorded waves on the seismogram (wave amplitude) is a greatly magnified representation of the actual ground
Il sismogramma è il grafico che rappresenta l’ampiezza del moto del suolo in funzione del tempo durante un terremoto. Le oscillazioni provocate dal terremoto vengono rilevate da appositi sismografi, che registrano in modo continuo il moto del suolo rispetto ad un sistema di riferimento inerziale. I moderni sensori sismici sono in grado di registrare accelerazione,
What are the different magnitude scales, and why are there so many? Earthquake size, as measured by the Richter Scale is a well known, but not well understood, concept. The idea of a logarithmic earthquake magnitude scale was first developed by Charles Richter in the 1930’s for measuring the size of earthquakes occurring in southern
What to Do Before an Earthquake Make sure you have a fire extinguisher, first aid kit, a battery-powered radio, a flashlight, and extra batteries at home. Learn first aid. Learn how to turn off the gas, water, and electricity. Make up a plan of where to meet your family after an earthquake. Don’t leave heavy
The following table lists the approximate energy equivalents in terms of TNT explosive force – though note that the earthquake energy is released underground rather than overground.[21] Most energy from an earthquake is not transmitted to and through the surface; instead, it dissipates into the crust and other subsurface structures. In contrast, a small
