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The Space Shuttle Solid Rocket Boosters (SRBs) are the pair of large solid rockets used by the United States' NASA Space Shuttle during the first two minutes of powered flight. The two reusable SRBs provide the main thrust to lift the shuttle off the launch pad and up to an altitude of about 150,000 ft (28 mi; 46 km). While on the pad, the two SRBs carry the entire weight of the external tank and orbiter and transmit the weight load through their structure to the mobile launch platform. Each booster has a liftoff thrust of approximately 2,800,000 pounds-force (12.5 MN) at sea level, increasing shortly after liftoff to about 3,100,000 lbf (13.8 MN). They are ignited after the three space shuttle main engines' thrust level is verified. Seventy-five seconds after SRB separation, SRB apogee occurs at an altitude of approximately 220,000 ft (42 mi; 67 km); parachutes are then deployed and impact occurs in the ocean approximately 122 nautical miles (226 km) downrange, after which the two SRBs are recovered. The SRBs are the largest solid-propellant motors ever flown and the first of such large rockets designed for reuse. Each is 149.16 ft (45.46 m) long and 12.17 ft (3.71 m) in diameter. Each SRB weighs approximately 1,300,000 lb (590,000 kg) at launch. The two SRBs constitute about 60% of the total lift-off mass. The propellant for each solid rocket motor weighs approximately 1,100,000 lb (500,000 kg). The inert weight of each SRB is approximately 200,000 lb (91,000 kg). Primary elements of each booster are the motor (including case, propellant, igniter and nozzle), structure, separation systems, operational flight instrumentation, recovery avionics, pyrotechnics, deceleration system, thrust vector control system and range safety destruct system. While the terms 'solid rocket motor' and 'solid rocket booster' are often used interchangeably, in technical use they have specific meanings. 'Solid rocket booster' applies to the entire rocket assembly, which includes the recovery parachutes, electronic instrumentation, separation rockets, range safety destruct system, and thrust vector control. The term 'solid rocket motor' applies to the propellant, case, igniter and nozzle. Each booster is attached to the external tank at the SRB's aft frame by two lateral sway braces and a diagonal attachment. The forward end of each SRB is attached to the external tank at the forward end of the SRB's forward skirt. On the launch pad, each booster also is attached to the mobile launcher platform at the aft skirt by four frangible nuts that are severed at lift-off. The boosters are composed of seven individually manufactured steel segments. These are assembled in pairs by the manufacturer, and then shipped to Kennedy Space Center by rail for final assembly. The segments are fixed together using circumferential tang, clevis, and clevis pin fastening, and sealed with three O-rings (two prior to the Challenger Disaster in 1986) and heat-resistant putty. The spent SRBs are recovered from the ocean, refurbished, reloaded with propellant, and reused for several missions. [READ THE REST OF THIS ARTICLE]



Chironex fleckeri, the infamous lethally venomous species of Box jellyfish living in northern Australia's coastal waters, is the most lethal jellyfish in the world, and one of the most dangerous animals in the world. The amount of venom in one animal is enough to kill 60 adult humans. First aid consists of washing the sting area with vinegar, and in no circumstance should alcohol, alcohol-based lotions, or methylated spirits be applied. Chironex fleckeri is best known for its incredibly powerful and often fatal sting. The sting produces excruciating pain accompanied by an intense burning sensation, and the venom has multiple effects attacking the nervous system, heart and skin at the same time. While an appreciable amount of venom (contact from about ten feet or three metres of tentacle) needs to be delivered in order to have a fatal effect on an adult human, the potently neurotoxic venom is extremely quick to act. Fatalities have been observed as little as four minutes after envenomation, notably quicker than any snake, insect or spider , and prompting its description as the world's deadliest venomous animal. Frequently a person swimming who gets stung will have a heart attack or drown before they can even get back to the shore or boat. Cardiopulmonary resuscitation (CPR) may be required. Medical help should be sought as soon as possible after considering these needs. Notorious for its dangerous sting, C. fleckeri tentacles, up to 3m long, are covered in thousands upon thousands of nematocysts which on contact release microscopic darts, each delivering an extremely powerful venom. Being stung invariably results in excruciating pain, and if the sting area is significant, an untreated victim may die in as little as 3 minutes. Swimmers who are stung face the additional risk of drowning. [READ THE REST OF THIS ARTICLE]



Frosty the Snowman is an American animated television special based on the popular song of the same title. The program, which first aired on December 7, 1969 on CBS, was produced for television by Rankin/Bass and featured the voices of comedians Jimmy Durante as narrator and Jackie Vernon as the titular character. This special marked the first use of traditional cel animation (as opposed to stop-motion animation) for Rankin/Bass in a Christmas special. Arthur Rankin, Jr. and Jules Bass wanted to give the show and its characters the look of a Christmas card, so Paul Coker, Jr., a greeting card and Mad magazine artist, was hired to do the character and background drawings. The animation was produced by Mushi Production in Japan, with then-Mushi staffer Osamu Dezaki among the animation staff. Rankin/Bass veteran writer Romeo Muller adapted and expanded the story for television as he had done with Rudolph the Red-Nosed Reindeer. TV Guide ranked the special number 4 on its 10 Best Family Holiday Specials list. In 1970, June Foray's voice was replaced by an uncredited voice (Foray's voice is still heard as Karen's singing voice, as well as other minor roles). The dubbing is also obvious on the DVD, as the audio quality of the replacement voice is better than that of the other sounds. The current restored version, which debuted in 2005, does not restore Foray's voice. At the time, rumors implied a controversy over copyrights and/or royalties as the reason behind the change, but the reason remains unknown. The original soundtrack with Foray's original voice track is available on CD. [READ THE REST OF THIS ARTICLE]







The Crazy Horse Memorial is a mountain monument under construction in the Black Hills of South Dakota, in the form of Crazy Horse, an Oglala Lakota warrior, riding a horse and pointing into the distance. The memorial consists of the mountain carving, the Indian Museum of North America, and the Native American Cultural Center. The monument is being carved out of Thunderhead Mountain on land considered sacred by some Native Americans, between Custer and Hill City, roughly 8 miles (13 km) away from Mount Rushmore. The sculpture's final dimensions are planned to be 641 feet wide and 563 feet high. The head of Crazy Horse will be 87 feet high; by comparison, the heads of the four U.S. Presidents at Mount Rushmore are each 60 feet high. The monument has been in progress since 1948 and is still far from completion. Crazy Horse resisted being photographed, and was deliberately buried where his grave would not be found. Ziolkowski, however, envisioned the monument as a metaphoric tribute to the spirit of Crazy Horse and Native Americans. "My lands are where my dead lie buried," supposedly said by Crazy Horse, is the intended interpretation of the monument's expansive gesture. While Lakota Chief Henry Standing Bear believes the motives may have been sincere, many traditional Lakota and Native Americans oppose this memorial. In a 2001 interview, the activist and actor Russell Means stated his objections to the memorial: "Imagine going to the holy land in Israel, whether you're a Christian or a Jew or a Muslim, and start carving up the mountain of Zion. It's an insult to our entire being." In a 1972 autobiography, Lame Deer, a Lakota medicine man, said: "The whole idea of making a beautiful wild mountain into a statue of him is a pollution of the landscape. It is against the spirit of Crazy Horse." To this day, the memorial remains controversial within the Native American community. The statue has been hit by lightning many times, many Natives believe this is because Crazy Horse never wanted his picture taken so the great spirits will ensure this statue will never be finished. If finished, it will be the world's largest statue. [READ THE REST OF THIS ARTICLE]



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