Taxonomy term

benchmarks

Benchmarks: September 16, 1987: Montreal Protocol Signed

Each year in late September to early October, atmospheric scientists watch with anticipation as ozone concentrations over Antarctica drop, opening a window in Earth’s defenses against harmful ultraviolet radiation. This ozone “hole” grew steadily in the 1990s and set a record for its size in 2006: At its peak, the hole covered an average area of 27 million square kilometers, approximately the size of North America. But scientists think that the overall ozone layer is on the slow road to recovery, thanks to the Montreal Protocol — one of the most successful international environmental agreements in history.
 
16 Sep 2009

Benchmarks: August 17, 1959: Hebgen Lake earthquake and landslide

By Callan Bentley

You’re camping in Montana, doing some fly fishing on the Madison River. You’ve had a full day of beautiful Big Sky country weather, and had fresh trout for dinner. In your campsite at the Rock Creek Campground, you go to bed satisfied and happy. It’s a nice enough evening that you sleep out in the open, to better appreciate the stars. The waters of the Madison gurgle by, gently lulling you to sleep while Orion shines above.

18 Aug 2009

Benchmarks: July 4, 1054: "Birth" of the Crab Nebula

On July 4, 1054, Chinese and Japanese astronomers observed a new, iridescent yellow point of light in the constellation Taurus. This “guest star,” said to be as bright as the moon, failed to disappear with the rising sun — for a month, it shone both night and day. Even after fading during daytime, it remained in the night sky for nearly two years, by some accounts. Historians and scientists think that this event was likely the supernova that created the Crab Nebula, one of the most spectacular and rare astronomical features in the known universe.
 
04 Jul 2009

June 9, 1938: Huang He Diversion: Largest Act of Environmental Warfare in History

By Nate Burgess

The Huang He (Yellow River) has been called “China’s Sorrow.” The name pays tribute to the millions killed by the river’s churning, muddy waters in a long history of dramatic diversions and massive floods. One of the most notable recent events in the river’s troubled history occurred in June 1938, when the Nationalist Chinese Army diverted the river to block invading Japanese troops. In both number of deaths and geographic scale, this event was the largest act of environmental warfare in modern history.

09 Jun 2009

Benchmarks: May 29, 1919: Solar eclipse "proves" relativity

By Nate Burgess

On May 29, 1919, the moon’s silhouette crept slowly over the sun, bringing premature night to observers in a broad swath of the Southern Hemisphere between South America and Africa. Few onlookers realized that this event would provide the first successful test of Albert Einstein’s theory of relativity.

01 Jun 2009

Benchmarks: April 26, 1986: Nuclear explosion at Chernobyl

By Carolyn Gramling

A rusting Ferris wheel dominates the skyline of Prypiat, Ukraine’s ghost town. A few kilometers away, within a massive concrete structure called the Sarcophagus, are the remnants of the worst nuclear disaster in history: the ruins of the Chernobyl Nuclear Power Plant’s reactor number four — and about 200 tons of highly radioactive material.

24 Apr 2009

Benchmarks: March 1, 1872: "Bone Wars" heat up

By Brian Fisher Johnson

Edward Drinker Cope stood before a smoke-filled audience at the American Philosophical Society in Philadelphia, Pa., on March 1, 1872. One of the nation’s leading paleontologists, Cope would present his latest fossil find: an extinct flying reptile he designated Ornithochirus. Certainly the piece would be recognized as a major contribution to the scientific understanding of ancient life. More importantly, Cope thought, he would receive credit as its discoverer.

27 Feb 2009

Benchmarks: January 3, 1961: Three men die in nuclear reactor meltdown

By Cassandra Willyard

Of the hundreds of thousands of caskets buried in Arlington National Cemetery, only one is lined with lead to prevent the body from leaking radiation. It holds the radioactive remains of Richard Leroy McKinley, one of three men killed when a nuclear reactor exploded in the nation’s only fatal nuclear accident.

02 Jan 2009

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