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Gemini 9A (officially Gemini IX-A) was a 1966 manned spaceflight in NASA's Gemini program. It was the 7th manned Gemini flight, the 13th manned American flight and the 23rd spaceflight of all time (includes X-15 flights over 100 km). One of the mission objectives was to dock with an Agena Target Vehicle in the same manner as the Gemini 8 mission. However, during the launch of the Gemini 9 Agena on May 17, 1966, its Atlas booster malfunctioned like it had on Gemini 6A, and it failed to make it to orbit. The first launch attempt of Gemini 9A was on June 1. The ATDA had launched perfectly into a 298 kilometre orbit, though telemetry from it indicated that the launch shroud had failed to open properly. But the Gemini spacecraft was not able to launch the same day as planned. At T-3 minutes, the ground computers could not contact the Gemini computers for some reason and the 40 second launch window opened and closed without the launch. This earned Tom Stafford the title of "Mayor of Pad 19." The second launch attempt went perfectly with the spacecraft entering into orbit. With this launch, Stafford could say that he had been strapped into a spacecraft six times ready for launch. Their first burn was 49 minutes after launch. They added 22.7 metres per second to their speed which put them in a 160 to 232 kilometres orbit. Their next burn was designed to correct phase, height, and out-of-plane errors. They pointed the spacecraft 40 down, and 3 to the 'left'. The burn added 16.2 metres per second to their speed and put them in a 274 by 276 kilometres orbit, closing at 38 metres per second on the ATDA. The first radar readings were when they were 240 km away and they had a solid lock at 222 km. Their first sight came 3 hours and 20 minutes into the mission when they were 93 km away. They noted that they could see the flashing lights on the ATDA designed to aid identification from a distance. This made them hope that the launch shroud had in fact been jettisoned and that the telemetry was wrong. As they got closer they found that in fact the shroud had half come off. Stafford described "It looks like an angry alligator out here rotating around". He asked if maybe he could use the spacecraft to open the 'jaws' but the ground decided against it. ATDA, a.k.a. the "Angry Alligator", as seen from Gemini 9The crew described how the shroud's explosive bolts had fired, but two neatly taped lanyards were holding the shroud together. It was decided that it would be too dangerous for an astronaut to cut the lines, as there were too many sharp edges around. The reason for the lanyards was soon discovered. Douglas built the shroud, but Lockheed attached it to the rocket, while McDonnell built the ATDA. A Douglas engineer had made a practice run with the McDonnell crew but didn't give them instructions on the final procedures which involved the lanyards. The McDonnell crew had the Douglas instructions for this procedure which said, "See blueprint", but there was no blueprint. So the McDonnell technicians decided to tape down the loose lanyards as it seemed like the sensible thing to do. On their 45th revolution of the Earth, they fired the retrofire rockets that slowed them down so that they would reenter. This time the computer worked perfectly, meaning they landed only 700 metres from the planned landing site and were close enough to see the prime recovery ship, the USS Wasp. The splashdown happened closer to the recovery ship than any other manned American spacecraft. [READ THE REST OF THIS ARTICLE]



The best-known rat species are the Black Rat (Rattus rattus) and the Brown Rat (Rattus norvegicus). The group is generally known as the Old World rats or true rats, and originated in Asia. Rats are bigger than most Old World mice, which are their relatives, but seldom weigh over 500 grams (1 lb) in the wild. The term "rat" is also used in the names of other small mammals which are not true rats. Examples include the North American pack rats, a number of species loosely called kangaroo rats, and others. Rats such as the Bandicoot rat (Bandicota bengalensis) are murine rodents related to true rats, but are not members of the genus Rattus. Male rats are called bucks, unmated females are called does, pregnant or parent females are called dams, and infants are called kittens or pups. A group of rats is either referred to as a pack or a mischief. Domestic rats differ from wild rats in many ways. They are calmer and less likely to bite; they can tolerate greater crowding; they breed earlier and produce more offspring; and their brains, livers, kidneys, adrenal glands, and hearts are smaller . Wild rats can carry many different "zoonotic" pathogens, such as e.g. Leptospira, Toxoplasma gondii and Campylobacter, and may transfer these across species, for example to humans. The Black Death is traditionally believed to have been caused by the micro-organism Yersinia pestis, carried by the Tropical Rat Flea which preyed on Black Rat living in European cities during the epidemic outbreaks of the Middle Ages; these rats were used as transport hosts. Today, this cycle still exists in many countries of the world and plague outbreaks still occur every year. The normal lifespan of rats ranges from two to five years, and is typically three years. Rats are edible by humans and are sometimes captured and eaten in emergency situations. For some cultures, rats are considered a staple. Bandicoot rats are an important food source among some peoples in Southeast Asia. Reasons why rat meat is not more widely eaten include the strong proscription against it in Halal and Kashrut tradition, and the fact that eating rat is not socially accepted in many cultures. Another argument against eating rat is the risk of Weil's disease: the British SAS's rule book lists rat as the only meat which its members in action are not allowed to eat. [READ THE REST OF THIS ARTICLE]





White blood cells (WBCs), or leukocytes, are cells of the immune system defending the body against both infectious disease and foreign materials. The number of WBCs in the blood is often an indicator of disease. Five different and diverse types of leukocytes exist, but they are all produced and derived from a multipotent cell in the bone marrow known as a hematopoietic stem cell. Neutrophils defend against bacterial or fungal infection and other very small inflammatory processes that are usually first responders to microbial infection; their activity and death in large numbers forms pus. Eosinophils primarily deal with parasitic infections and an increase in them may indicate such. Eosinophils are also the predominant inflammatory cells in allergic reactions. The most important causes of eosinophilia include allergies such as asthma, hay fever, and hives; and also parasitic infections. Basophils are chiefly responsible for allergic and antigen response by releasing the chemical histamine causing inflammation. Lymphocytes are much more common in the lymphatic system. Lymphocytes are distinguished by having a deeply staining nucleus which may be eccentric in location, and a relatively small amount of cytoplasm. The blood has three types of lymphocytes: B cells, T cells, and Natural killer cells. Natural killer cells are able to kill cells of the body which are displaying a signal to kill them, as they have been infected by a virus or have become cancerous. Monocytes share the "vacuum cleaner" (phagocytosis) function of neutrophils, but are much longer lived as they have an additional role: they present pieces of pathogens to T cells so that the pathogens may be recognized again and killed, or so that an antibody response may be mounted. The name "white blood cell" derives from the fact that after centrifugation of a blood sample, the white cells are found in the buffy coat, a thin, typically white layer of nucleated cells between the sedimented red blood cells and the blood plasma. [READ THE REST OF THIS ARTICLE]





SS Edmund Fitzgerald was an American Great Lakes freighter launched on June 8, 1958. Fitzgerald left Superior, Wisconsin, on the afternoon of Sunday, November 9, 1975, under the command of Captain Ernest M. McSorley. It was en route to the steel mill on Zug Island, near Detroit, Michigan, with a full cargo of taconite. A second freighter under the command of Captain Jesse B. "Bernie" Cooper, Arthur M. Anderson, destined for Gary, Indiana out of Two Harbors, Minnesota, joined up with Fitzgerald. Fitzgerald, being the faster ship, took the lead while Anderson trailed not far behind. The weather forecast was not unusual for November and called for a storm to pass over eastern Lake Superior and small craft warnings. Late in the afternoon of Monday, November 10, sustained winds of 50 knots were observed across eastern Lake Superior. Anderson was struck by a 75-knot (86 mph) hurricane-force gust. At 3:30 p.m., Captain McSorley radioed the Anderson to report that she was taking on water and had top-side damage including that the Fitzgerald was suffering a list, and had lost two vent covers and some railings. Two of the Fitzgerald's six bilge pumps were running continuously to discharge shipped water. At about 3:50 p.m., McSorley called the Anderson to report that his radar was not working and he asked the Anderson to keep them in sight while he checked his ship down so that the Anderson could close the gap between them. Fitzgerald was ahead of Anderson at the time, effectively blind; therefore, she slowed to come within 10 miles range so she could receive radar guidance from the other ship. Around 5:30 p.m., Woodward called the Fitzgerald again to report that the Whitefish point light was back on but not the radio beacon. When McSorley replied to the Avafors, he commented, "We're in a big sea. I've never seen anything like it in my life." The last communication from the doomed ship came at approximately 7:10 p.m., when Anderson notified Fitzgerald of an upbound ship and asked how it was doing. McSorley reported, "We are holding our own." A few minutes later, it apparently sank; no distress signal was received. Ten minutes later Anderson could neither raise Fitzgerald by radio, nor detect it on radar. At 8:32 p.m., Anderson was finally able to convince the U. S. Coast Guard that the Fitzgerald had gone missing. The large waves of the storm play a role in all of the published theories regarding her sinking; they differ on the other contributing causes. When Fitzgerald first vanished, it was widely believed the boat had snapped in half on the lake surface owing to storm action. Similar surface breakups in the past suggested bow and stern sections would be found miles apart on the lake floor. When underwater surveys revealed these sections were just yards from each other, it was initially concluded that Fitzgerald had instead separated upon hitting the lake floor. A Coast Guard investigation postulated that the accident was caused by ineffective hatch closures. These devices were unable to prevent waves from inundating the cargo hold. The flooding occurred gradually and probably imperceptibly throughout the final day, and finally resulted in a fatal loss of buoyancy and stability. As a result, the boat plummeted to the bottom without warning. Another published theory contends that an already weakened structure, and modification of the winter load line (allowing heavier loading, and travel 39" lower in the water) contributed to the large waves causing a stress fracture in the hull. It postulated this based on the "regular" huge waves of the storm, i.e. not necessarily involving rogue waves. The sinking of the Edmund Fitzgerald is the most famous disaster in the history of Great Lakes shipping. At the time of its launching, it was one of the first boats to be at or near maximum "St Lawrence Seaway Size" which was 730 feet (220 m) long and 75 feet (23 m) wide. From its launching in 1958 until 1971 the Fitzgerald continued to be one of the largest boats on the Great Lakes. The disaster was the subject of Gordon Lightfoot's 1976 hit song, "The Wreck of the Edmund Fitzgerald". [READ THE REST OF THIS ARTICLE]



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