the tet offensive
The calendar is intended to mark the number of years since the death of King Herod the Great. The Roman abbot Dionysus Exiguus devised the new Christian calendar in 533. He knew that it was impossible to say when Jesus was born, but he knew, or thought he knew, when Herod died. So, he chose to begin his Christian calendar on the year of Herod's death, and he based this on the reign of the Roman emperor Augustus. Unaware that Augustus only adopted that name four years after his reign began, going by his birth name of Octavius until then, Exiguus commenced his calendar just 4 years too late.
the nuclear fusion of hydrogen into helium
The nuclear fusion of hydrogen into helium
The Storming of Bastille
Puberty
Black Tuesday
A sentinel moment is a crucial or pivotal point in time that often marks a significant change or event. It can serve as a turning point or a moment of great importance.
The summer solstice.
A day that marks as a sad or unfortunate event
the mass extiction
balls
fusion of hydrogen atoms into helium atoms