Ancient relic points to a turning point in Earth's history 42,000 years ago Just like in The Hitchhiker's Guide to the Galaxy, the answer was 42
Sunday PM (SitNews) - The temporary breakdown of Earth's magnetic field 42,000 years ago sparked major climate shifts that led to global environmental change and mass extinctions, a new international study co-led by UNSW Sydney and the South Australian Museum shows. This dramatic turning point in Earth's history - laced with electrical storms, widespread auroras, and cosmic radiation - was triggered by the reversal of Earth's magnetic poles and changing solar winds. Using an ancient kauri tree log from Ng?wh?, New Zealand, scientists have dated the timing and environmental impacts of the last magnetic pole switch.