James Riddle Hoffa(also known as Jimmy Hoffa), one of the most influential American labor leaders of the 20th century, disappears in Detroit, Michigan, never to be heard from again. Though he is popularly believed to have been the victim of a Mafia hit, conclusive evidence was never found, and Hoffa's death remains shrouded in mystery to this day.
Jimmy Hoffa Video Link
Thursday, July 31, 2008
Tuesday, July 29, 2008
NASA's 50th Anniversary
The National Aeronautics and Space Administration (NASA, ) is an agency of the United States government, responsible for the nation's public space program. NASA was established on July 29, 1958, by the National Aeronautics and Space Act. In addition to the space program, it is also responsible for long-term civilian and military aerospace research. Since February 2006 NASA's self-described mission statement is to "pioneer the future in space exploration, scientific discovery, and aeronautics research." NASA's motto is: "For the benefit of all". The motto of NASA's Office of Education is: Shaping the Future: Launching New Endeavors to Inspire the Next Generation of Explorers. Following the Soviet space program's launch of the world's first human-made satellite (Sputnik 1) on 4 October, 1957, the attention of the United States turned toward its own fledgling space efforts. The U.S. Congress, alarmed by the perceived threat to U.S. security and technological leadership
Saturday, July 26, 2008
Friday, July 25, 2008
Tuesday, July 22, 2008
Monday, July 7, 2008
July 7: 1930 : Building of Hoover Dam begins
On this day in 1930, construction of the Hoover Dam begins. Over the next five years, a total of 21,000 men would work ceaselessly to produce what would be the largest dam of its time, as well as one of the largest manmade structures in the world.
Although the dam would take only five years to build, its construction was nearly 30 years in the making. Arthur Powell Davis, an engineer from the Bureau of Reclamation, originally had his vision for the Hoover Dam back in 1902, and his engineering report on the topic became the guiding document when plans were finally made to begin the dam in 1922.
Herbert Hoover, the 31st president of the United States and a committed conservationist, played a crucial role in making Davis’ vision a reality. As secretary of commerce in 1921, Hoover devoted himself to the erection of a high dam in Boulder Canyon, Colorado. The dam would provide essential flood control, which would prevent damage to downstream farming communities that suffered each year when snow from the Rocky Mountains melted and joined the Colorado River. Further, the dam would allow the expansion of irrigated farming in the desert, and would provide a dependable supply of water for Los Angeles and other southern California communities.
Even with Hoover's exuberant backing and a regional consensus around the need to build the dam, Congressional approval and individual state cooperation were slow in coming. For many years, water rights had been a source of contention among the western states that had claims on the Colorado River. To address this issue, Hoover negotiated the Colorado River Compact, which broke the river basin into two regions with the water divided between them. Hoover then had to introduce and re-introduce the bill to build the dam several times over the next few years before the House and Senate finally approved the bill in 1928.
In 1929, Hoover, now president, signed the Colorado River Compact into law, claiming it was "the most extensive action ever taken by a group of states under the provisions of the Constitution permitting compacts between states."
Once preparations were made, the Hoover Dam's construction sprinted forward: The contractors finished their work two years ahead of schedule and millions of dollars under budget. Today, the Hoover Dam is the second highest dam in the country and the 18th highest in the world. It generates enough energy each year to serve over a million people, and stands, in Hoover Dam artist Oskar Hansen's words, as "a monument to collective genius exerting itself in community efforts around a common need or ideal."
Thursday, July 3, 2008
Stars and a Stripe in Celestial Fireworks
A delicate ribbon of gas floats eerily in our galaxy. A contrail from an alien spaceship? A jet from a black-hole? Actually this image, taken by NASA's Hubble Space Telescope, is a very thin section of a supernova remnant caused by a stellar explosion that occurred more than 1,000 years ago.
Around May 1, 1006 A.D., observers from Africa to Europe to the Far East witnessed and recorded the arrival of light from what is now called SN 1006, a tremendous supernova explosion caused by the final death throes of a white dwarf star nearly 7,000 light-years away. The supernova was probably the brightest star ever seen by humans, and surpassed Venus as the brightest object in the night time sky, only to be surpassed by the moon. It was visible even during the day for weeks, and remained visible to the naked eye for at least two and a half years before fading away.
It wasn't until the mid-1960s that radio astronomers first detected a nearly circular ring of material at the recorded position of the supernova. The ring was almost 30 arcminutes across, the same angular diameter as the full moon. The size of the remnant implied that the blast wave from the supernova had expanded at nearly 20 million miles per hour over the nearly 1,000 years since the explosion occurred.
Today, SN 1006 has a diameter of nearly 60 light-years, and it is still expanding at roughly 6 million miles per hour. Even at this tremendous speed, however, it takes observations typically separated by years to see significant outward motion of the shock wave against the grid of background stars. In the Hubble image as displayed, the supernova would have occurred far off the lower right corner of the image, and the motion would be toward the upper left.
Image Credit: NASA, ESA, and the Hubble Heritage Team (STScI/AURA)
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