Spaceflight 1 (unmanned), 25 September 2013 !Though space flight provides a great deal of information about the universe by 1.allowing astronomers to see light that can't pass earth's atmosphere, it is never well explained by textbooks.!Textbook writers are always looking to cut information, and space flight is A.often the victim of this.!History of Rocketry !2.About a thousand years ago, gun powder was invented in China and used as A.a weapon against China's enemies (the Mongols).!Gun powder was used as a weapon in several ways: !a.Guns like pistols and muskets. !1.Mortars and cannons. !2."Fire arrows"!3.No one is exactly sure what these looked, but they were early A.rockets used to catch the camps of enemies on fire. !They were difficult to aim for specific damage and easily backfired, B.but they were a good weapon of terror. !They remained a fairly minor weapons for their drawbacks, a.though.!The use of gunpowder as a weapon (including in rockets), spread through B.Asia into Europe. !This was caused by cultural diffusion through war: When the Mongols a.took over China, they started using fire arrows against their enemies in central asia. The Mongol's enemies' enemies in central asia captured a few rockets, and started using them against the Persians, who captured a few to use against the Turks, who used them against the Europeans.!When rockets reached Britain, William Congreve improved their design to C.make them useful in naval warfare. ! William Congreve (1772-1828): !a.He was a British armament expert at a Royal Military Arsenal. !1.He invented the Congreve rocket, which became an effective weapon 2.in the Napoleonic Wars (in Europe) and the War of 1812 (in the US).!Ships were made of wood, sails, and canvas at the time, so a well A.aimed rocket could burn enemy ships down to sea level. !The use of these rockets against the United States at the Battle of B.Fort McHenry (during the War of 1812) inspired Francis Scott Key to write a line of the Star Spangled Banner.!"And the rockets' red glare, the bombs bursting in air,"!a.(1860s) The development of Congreve rockets stopped when 3.unignitable iron ships with steam engines replaced wooden ships with canvas sails.!Though rockets were no longer used in warfare, people still knew A.about them. !Further research into rocketry was motivated by "inspiring science fiction" D.in which rockets were used to explore space. !Authors of Inspiring Science fiction: !a.Jules Verne (1828-1905)!1.Herbert George Wells (1866-1946)!2.Almost every great rocket designer said they were inspired to go into b.rocketry by reading the science fiction of the late 1800s and early 1900s. !The quality of these stories shows in that they have never been out of 1.print since they were published. !These books magnified popular interest in space travel. !2.Key Rocket designers and builders: !E.Konstantin Tsiolkovsky (1857-1935), Russian!a.Did airship design (dirigibles) in the 1880s, and then rocket design 1.until the 1920s.!A great designer with excellent ideas, but not a very good builder.!2.First person to design the rockets that would be the ancestors of A.those that went into space, but did not build any himself.!Though he was barley recognized by the authorities in Tsarist Russia, 3.Tsiolkovsky was appreciated after the Soviets took over after WWI.!Robert H Goddard (1882-1945), American!b.Professor of physics at Clark College in Worcester, Massachusetts!1.Got a grant from the Navy to design rockets. !2.Made the first liquid fueled rocket in 1926.!A.Before, all rockets were solid fuel (gun powder or other a.explosive). As soon as you set off these rockets, you could not control them. !Liquid fuel could be throttled, and therefore the rockets could b.be better controlled.!The design of the first rocket contained a lot of first guesses, a c.lot of which were incorrect: !The rocket engine was on the top of the plane, and was 1.supplied by 2 different tanks containing fuel and oxidizer on the back of the rocket. There was an asbestos cap in the middle to protect the fuel tanks from the flames of the rocket. !It successfully launched, although it did not get very far. !A.Built rockets of increasing size (and complexity):!B.Though the first rockets were small enough to set off the first a.rockets on the Clark campus green, he had to move out to his Aunt's farm, and eventually a desert in Roswell, New Mexico to prevent damages.!The last liquid rocket he made in 1941 was larger and much b.more complicated that the first. !Goddard's work on rocketry was put on hold when the US became 3.involved in WWII. !During this time he helped to engineer a rocket launched grenade A.called a Bazooka, and jet assisted take off for airplanes on short landing fields/aircraft carriers.!Goddard died of cancer in 1945 before he could return to his work 4.on space rockets. !Hermann Oberth (1894-1989), German!F.Born in Romania, but he claimed he was of German heritage and spoke a.German. !After WWI, he spent most of his time in Weimar Republic Germany. !b.Though Germany was crushed under reparations and inflation, he was 1.able to join and eventually lead a hobby group called the German Rocket Club (VFR). !He was a designer and builder of rockets which this club set off in A.abandoned fields. !He provided special effects for a science fiction movie about B.traveling the moon (Frau im Mond, Woman in the Mon).!He was honored before and after WWI. !2.Wernher von Braum (1912-1977), German!G.(1930s) Joined the VFR as a teenager, where he learned a lot about a.rocket engineering. !He was on the crash crew, which means he collected rocket parts to 1.analyze what went wrong and how to improve them. !From this he learned that "it's the little things that kill you," ie, the A.minor details that mess you up.! Space is hostile, and the materials and devices of rockets must a.be pushed to their extreme.!When the Nazi party came into power, they forced the VFR (including b.von Braum) to build armaments.!They were responsible for building the V1 and V2 rockets, the second 1.of which was capable of supersonic speeds.!The fact that the V2 rocket was faster than the speed of sound A.made them a good weapon of terror to use against English cities. !von Braum was one of the principal designers of the V2, but he 2.claimed that he slowed down development as much as he could.!How much he collaborated is debatable, but it is true that he never A.joined the Nazi party and was imprisoned by them.!At the end
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