Experience History:
250 Years Since the First Shots of the American Revolution
250 Years Since the First Shots of the American Revolution
Down to Earth
As Earth Day celebrates its 55th anniversary this week, many scientists are trying to meet the moment to address global warming. Despite global and regional heat records continuing to fall year after year because of carbon dioxide emissions from fossil fuels, alternative energy generation from solar, wind, and other sources continues to expand globally, as are efforts to extract carbon from the atmosphere and the seas. Still, daunting challenges remain: studies reveal that microplastics have spread through all ecosystems, and more than 47,000 species globally are threatened with extinction. Earth Day reminds us that we are stewards of the planet and that all of us must work together to make a better, cleaner, more prosperous world.
The History of Earth Day
Hulton Archive/Getty Images
Interactive Timeline: Milestones in Environmentalism
Win McNamee/Getty Images

Enrique Salmón Explains the Dangers of Biodiversity Loss
Encyclopædia Britannica, Inc.
More Work to Do
Henry the Eighth, I Am
On April 21, 1509, Henry VIII ascended to the throne of England upon the death of his father, Henry VII. Because of the secrecy surrounding Henry VII’s health in his final days, however, a full 48 hours would pass before the 17-year-old Henry would learn that the crown had passed to him. He is perhaps best remembered for his six marriages and the manner in which they ended.
Hilary Mantel’s trilogy about the rise and (spoiler) fall of Thomas Cromwell provides a fascinating if fictionalized view of life in Henry’s court.
From defender of the faith to excommunicantHenry’s stance on marriage meant that you can’t keep his wives straight without a helpful mnemonic: divorced, beheaded, died, divorced, beheaded, survived.

Hulton Archive—Hulton Royals Collection/Getty Images
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