Taxonomy term

benchmarks

March 29, 1936: Notes on Earth's Inner Core

On March 29, 1936, Danish seismologist Inge Lehmann wrote a letter to a colleague in which she argued that seismic waves — specifically P-waves — recorded from distant earthquakes showed some anomalous characteristics. “If you had seen so many records from these distances as I have,” she wrote, “I am sure you would not doubt that the amplitudes are abnormally small.” Within the year, Lehmann published a study based on those unusual amplitudes, work that first proposed that Earth has a solid inner core inside its liquid outer core.

29 Mar 2015

Benchmarks: February 17, 1977: Hydrothermal vents are discovered

In early February 1977, as scientists aboard the research vessel (R/V) Knorr made their way across the Pacific waters off the northwest coast of South America, they had reason to suspect their expedition might find the success that had eluded others. Previous missions had identified their destination — a site on the ocean surface about 330 kilometers northeast of the Galápagos Islands, below which two tectonic plates rift apart — as a promising location from which to search for their intended target. Once there, the researchers would deploy a variety of tools, including manned and unmanned submersibles, to the ocean bottom in the hopes of directly spotting hydrothermal vents.

17 Feb 2015

Conjunction injunction: Recent and future planetary alignments

February 1962: The five planets visible to the naked eye, as well as the sun and moon, all appeared within 17 degrees of each other in the sky. A concurrent solar eclipse and new moon made it possible to view the planets.

04 Feb 2015

Benchmarks: January 3, 1970: Lost City meteorite is tracked and recovered

On the evening of Saturday, Jan. 3, 1970, residents of northeastern Oklahoma saw a fireball as bright as a full moon blaze across the sky. The nine-second light display was accompanied by a sonic boom heard over a 1,000-square-kilometer area.

 
03 Jan 2015

Benchmarks: December 26, 2004: Indian Ocean tsunami strikes

On Dec. 26, 2004, a magnitude-9.2 earthquake ruptured the seafloor off Indonesia, sending the most destructive tsunami in recorded history across the Indian Ocean. A wall of water and debris slammed the shores of South Asia; some witnesses described it as sounding like a freight train. Tourists and locals alike scrambled to safety inland and atop tall hotels, recording videos of the surging water that inundated their communities. Many were unable to reach higher ground.

26 Dec 2014

Benchmarks: November 8, 2013: Super-typhoon Haiyan tests Philippines warning protocols

On the morning of Nov. 8, 2013, Super-Typhoon Haiyan struck the east-central Philippines with sustained wind speeds exceeding 300 kilometers per hour. In a mere eight hours, the storm cut a path of total devastation over an area of 300 square kilometers, an area roughly the size of Seattle. More than 7,800 people were confirmed dead or missing and 27,000 injured; more than 4 million were displaced from their homes. Economic losses to homes, infrastructure and agriculture reached more than $12 billion (U.S.).

08 Nov 2014

Benchmarks: October 10, 1913: Atlantic and Pacific waters meet in the Panama Canal

On Oct. 10, 1913, U.S. President Woodrow Wilson pressed a button in his Washington, D.C., office. At that moment, more than 6,400 kilometers away, about seven metric tons of dynamite exploded, clearing the final obstruction in the Panama Canal. Deep within the Culebra Cut, waters from the Atlantic Ocean finally met waters from the Pacific Ocean, marking the end of major construction on the 77-kilometer-long canal.

09 Oct 2014

Benchmarks: October 9, 1963: The Vajont Landslide kills 2,500 in Italy

In 45 seconds, everything changed. What had been a towering mountainside collapsed into a pile of rubble; what had been a deep reservoir of placid water became a lethal flood; what had been a valley of small Italian villages was leveled to a barren outwash plain.

09 Oct 2014

Benchmarks: September 1, 1957: Fossil Cycad National Monument is dissolved

On Sept. 1, 1957, with the stroke of a pen, the U.S. Congress declared Fossil Cycad National Monument in the Black Hills of South Dakota to be no more. At one time, the site held the world’s largest collection of rare fossil cycad-like plants that thrived during the Cretaceous. Over the years, mismanagement, vandalism and theft left the site barren of fossils — the site never had a staff or visitor center, and was never opened to the public. The site’s initial designation as a national monument, in October 1922, had been brought about by the crusading of one man, Yale University paleobotanist George R. Wieland; in the end, he was also responsible for its demise.

01 Sep 2014

Benchmarks: June 16, 1963 & June 18, 1983: Valentina Tereshkova and Sally Ride become first and third women in space

On June 16, 1963, during the height of the Cold War, Valentina Tereshkova became the first woman to fly in space. It would be 19 years before another woman would fly in space — Soviet Svetlana Savitskaya in 1982 — and 20 years before the first American woman, Sally Ride, made it into space on June 18, 1983. These pioneers inspired the generations of women astronauts who followed. In the three decades since Ride’s foray into outer space, 57 other women have also taken flight (see sidebar) and, last year, half of NASA’s new class of astronauts were women.

16 Jun 2014

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