This last major geomagnetic reversal triggered a series of dramatic events that have far-reaching consequences for our planet. They read like the plot of a horror movie: the ozone layer was destroyed, electrical storms raged across the tropics, solar winds generated spectacular light shows auroras , Arctic air poured across North America, ice sheets and glaciers surged and weather patterns shifted violently. During these events, life on earth was exposed to intense ultraviolet light, Neanderthals and giant animals known as megafauna went extinct, while modern humans sought protection in caves. The magnetic north pole — where a compass needle points to — does not have a permanent location. For reasons still not entirely clear, magnetic pole movements can sometimes be more extreme than a wobble. One of the most dramatic of these pole migrations took place some 42, years ago and is known as the Laschamps Excursion — named after the village where it was discovered in the French Massif Central.
Archaeological Dating Methods
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A lunar calendar is a calendar based on the monthly cycles of the Moon 's phases synodic months , in contrast to solar calendars , whose annual cycles are based only directly on the solar year. The most commonly used calendar, the Gregorian calendar , is a solar calendar system that originally evolved out of a lunar calendar system. A purely lunar calendar is also distinguished from a lunisolar calendar , whose lunar months are brought into alignment with the solar year through some process of intercalation. The details of when months begin varies from calendar to calendar, with some using new , full , or crescent moons and others employing detailed calculations.
The flute is a family of musical instruments in the woodwind group. Unlike woodwind instruments with reeds , a flute is an aerophone or reedless wind instrument that produces its sound from the flow of air across an opening. According to the instrument classification of Hornbostel—Sachs , flutes are categorized as edge-blown aerophones. Flutes are the earliest known identifiable musical instruments , as paleolithic examples with hand-bored holes have been found. A number of flutes dating to about 43, to 35, years ago have been found in the Swabian Jura region of present-day Germany.