The way the Earth changes its tilt. See 'A Brief History of Climate Change'.
Obliquity
Fact of the Day
In France around the year 1000, a pale complexion, squeamishness and vegetarianism were all signs of heresy.
Quote of the Day
"No-one loves armed missionaries
"
~ Robespierre, 1792
On This Day
1282 The last native Prince of Wales, Llewelyn ap Gruffydd, died
1688 King James II tried to flee to France during the Glorious Revolution. He was captured but allowed to escape again later that month.
1936 Edward VIII abdicated in order to marry American divorcee and socialite Wallis Simpson.
1941 Germany and Italy declared war on the USA.
1972 Apollo 17 became the last mission to land on the moon.