The First Interlude. What is an interlude in this course?

Transcription

1 The First Interlude What is an interlude in this course? This course (Phys 171 'Planetary and Stellar Astronomy') is a College 200 course for the new curriculum which applies to the incoming freshmen this year. (It is also is a GER II Course under the old curriculum.) As a college 200 course, we will be looking at connections between our area (astronomy) and other areas such as art, social sciences, humanities, politics, the military, and theology. The 'interlude' is a 1 week period where we will look at the space race between the US and USSR in the cold war. 1

2 The Interlude What will you be expected to do? On the class web page under class notes is a link to information for the interlude. After looking at the material, you will be ask to do a project on the material. The interlude web page also includes references which you may find useful. 2

3 The Interlude Possible projects which will be part of your overall grade: A 'reaction paper'. A class presentation (7-10 minutes with slides 2-4 people). Talk to me about scheduling your presentation. Time slots are limited. A video of 3-7 minutes. It will be shown in class as time permits A poster to display during/after class. A painting or other artwork with a short description. (one student has already requested this option!) Other projects. Please talk to me about other ideas for a project. Except for the reaction paper, please let me know your intentions so I can schedule class time if necessary. 3

4 The Interlude What are the details of the 'reaction paper'? The paper should be 500 words (2 typed pages double spaced) in length. Reference to outside sources should be include but can be URLs (web links) The paper is due on Friday (October 13 th ) by the end of class. The paper (and all projects) should not be about the details of astronomy done as the result of the space race. The reaction paper should relate to other areas that were effected by the space race or how other areas effected the space race. Short answer: 2 pages. How the space race changed the world and/or society. 4

5 The Interlude What do I plan for our class time? I would like to cover some topics about the history of rockets and their non-astronomy uses. I will reserve time for a class discussion and student presentations, videos, posters etc. 5

6 Yuan Dynasty hand cannon dated to Chinese fire arrow Gunpowder was invented in China in the 9 th century. Gunpowder is composed of sulfur, charcoal, and potassium nitrate (saltpeter). It is classified as a low explosive because of its relatively slow burn rate. It was first used in guns and fireworks. Later 'fire arrows' were developed. In 1232 the Chinese used rockets to repel Mongol invaders with a barrage of "arrows of flying fire." The Mongols later introduced gunpowder to 6 central Asia and into Europe.

7 Newton's laws of motion explained how rockets work and put their development on a scientific basis. In 1792 and again in 1799 Indians used rockets against the British in India. From this experience, William Congreve developed the 'Congreve rocket' which was used for artillery purposes. They are the famous 'rocket's red glare' in the The Star- Spangled Banner. 7

8 Rockets fell out of use for artillery purposes in the last part of the 19th century with the development of explosives for gun based artillery and rifling of artillery tubes for better accuracy. Interest in rockets continued with academics, rocket clubs and science fiction writers. 8

9 The Russian academic Konstantin E. Tsiolkovsky ( ) published some of the first modern work on rockets. In 1903 he published an article containing the 'rocket equation': Δv = v e ln(m 0 /m f ) where Δv is the change in velocity of the rocket with no external forces acting, v e is the escape velocity of the exhaust, m 0 and m f and the initial mass of the fueled rocket and final mass of the rocket (after the fuel is 9 burned), respectively.

10 Late 19 th and early 20 th century science fiction brought ideas of space travel with rockets into the popular culture. Jules Verne's 'From the Earth to the Moon' (1865) was an early science fiction story about a trip to the Moon. H.G. Wells 'The War of the World' is a story about a Martian invasion of Earth. 10

11 Robert Goddard was an American physicist at Clark Univ who developed theoretical and experimental aspects of rocketry. He independently derived Tsiolkovsky's rocket equation and developed a liquid fuel rocket. During WW I he developed a precursor to the bazooka (recoil free, rocket powered weapon) for the US Army as well as other ideas for naval torpedoes and mobile field artillery. 11

12 In 1926 he launched his first rocket. It used liquid oxygen and gasoline. The rocket rose to 41 ft during a flight of 2.5 seconds. 12

13 A Smithsonian press release in 1920 about Goddard's research was reported on the front pager of the NY Times. "Believes Rocket Can Reach Moon" was the headline. A later unsigned New York Times editorial: That Professor Goddard, with his "chair" in Clark College and the countenancing of the Smithsonian Institution, does not know the relation of action and reaction, and of the need to have something better than a vacuum against which to react to say that would be absurd. Of course he only seems to lack the knowledge ladled out daily in high schools. The editorial writer obviously did not understand Newton's 3 rd law! 13

14 In the late 1920s, a German rocket enthusiast purchased a copy of Die Rakete zu den Planetenräumen (The Rocket into Interplanetary Spaces) which motivated him to study engineering where he received his Ph.d. about the time that the Nazis (NSDAP) gained power in Germany. His name was Wernher von Braun. Before WW II started in 1939, there was contact between Goddard in the US and von 14 Braun's group.

15 A major research effort was undertaken by a group lead by von Braun at Peenemünde on the Baltic coast. The research was financed by the German military. The results of the work at Peenemünde was the V2 (Vergeltungswaffe 2 or "Retribution Weapon 2") rocket. The V2 was the first rocket able to reach high altitude (88 km) and have a long range (320 km). It reached speeds of 5760 km/hr and carried a 1 ton 15 warhead.

16 The V2 was built with slave labor by the Nazis in an underground factory. The weapon was mobile so it was difficult to find and destroy V2s were successfully launched mainly at the UK and Belgium (against the advancing Allies and ports.) The V2 come in so fast no warning was possible. Thousands of people were killed. 16

17 When Nazi Germany surrendered, the underground factory was captured by the American Army but was in the Soviet occupation zone. The V2s were quickly removed. Over 300 train cars of V2 rockets and parts were sent to the US. Von Braun's team was captured in the western area of Germany and also send to the US. The Soviets captured the factory and the remaining engineers at the site. 17

18 After the war, the US and Soviets continued the development of rockets based on the German work. The work was done by the military of both countries. With the advent of the nuclear weapons, the purpose was to develop a defense-proof delivery system for nuclear weapons, an intercontinental ballistic missile (ICBM). Early improved V2 were the basis for short ranged military rockets like the Soviet 'Scud'. 18

19 The Space Race Begins In July of 1955 President Eisenhower announced the US would launch an Earth satellite for the International Geophysical Year in On October 4 th, 1957, the Soviet Union place 'sputnik' Into a low Earth orbit. It was the first man-made satellite. It was launched with the Soviet R-7 Semyorka rocket which was also the first Soviet ICBM. The R-7 was developed by Sergei Korolev, the Soviet 'van Braun'. 19

20 The US tried to launch a satellite in December of It failed and blow up on the launch pad. In January of 1958, the US successfully launched Explorer 1 with an Army rocket developed from the Redstone missile. The Soviets with their larger rockets quickly launched sputnik II with a dog. After some failures, Luna 1 was sent to the Moon. 20

21 The Space Race Begins The US lagged behind the space race with the Soviets for several years. The Soviets sent the first man into space in 1961 on a 1 orbit flight. The Soviets launched the first multiple passenger space craft and the first woman in space. In 1961 the Mercury program launched astronauts with a modified Atlas missile. The first Mercury flights were suborbital. In 1962, John Glenn made the first US orbital flight. In May of 1961, President Kennedy gave a speech where he proposed to put a man on the Moon by the end of the decade and return him safely to Earth. The space race was on. 21

22 Class discussion Topic The invention and development of rockets has had many positive effects for society. Better weather forecasts especially for hurricanes and storms. Better communications with satellites, especially in geosynchronous orbits Better monitoring of the environment of Earth Discovery of new resources. Better information about military assets and intentions of adversaries (spy satellites). 22

23 Class discussion Topic Rockets were developed mainly for military reasons. This has not been a positive thing: ICBMs and SLBMs have threatened the entire world with nuclear holocaust. Short and longer range rockets are common, lethal and often indiscriminate weapons of war and terror. 23

24 Class discussion Topic Technology like rockets can be used for good and bad purposes. Who should decided how a technology is used? Are there technologies that should not be developed. Can a technology be held as a secret by any group for long periods of time? 24