Introduction to Space Flight New Notes 1. Which of the following is not a Planetary mission type? Flyby, Orbiter, Lander, Rover, Atmospheric probe 2. Spacecraft mission types: Planetary/ Solar system exploration, Astronomical observation, Communications, Survey and remote sensing, reconnaissance (DoD), Technology advancement 3. Classifications: flyby orbiter, atmospheric probe, atmospheric ballon, lander, surface rover, surface penetrator. 4. Mission elements: 1. Launch vehicle and control center and operations 2. Ground link segment 3. Spacecraft segment 4. Communications and telemetry 5. Command and control 6. Target/objective 7. Support services logistics, data, management Spacecraft Systems 5. What is a spacecraft bus? Primary spacecraft structure provides places for instruments, protection, propulsion, etc. 6. Space dangers, protection provided by the bus: 1. High radiation 2. Temperatures 3. Micrometeroid impact 4. Electric and magnetic field isolation. 7.Characteristics of a bus: 1. Lite 2. Strong 3. Durable 4. Easy to make 5. Resistant to space dangers Electrical Power system 8. Primary source: main source 9. Secondary source: stored energy for power interruptions 10. Primary power sources: Solar cell good to Mars orbit; Fuel cells mid-duration missions, near earth, fuel +oxidizer; Batteries: short duration missions;. Nuclear thermal good for long term missions-plutonium fuel, perfect safety record. Telecommunications 11. Components: Transmitter, receiver, antenna, command and data systems 12. Uplink: commands from ground station to spacecraft 13. Downlink transmissions from spacecraft to receiving stations. Frequencies of uplink and downlink are different, so both go happen at the same time. Environmental Control/Life Support 14. Passive Thermal Control can be provided by: coatings, insulation, conduction 15. Active thermal control: by refrigeration loops, electrical heaters, shutters, radiators, heat pipes, rotation 16. Heat sources: solar radiation, Spacecraft systems, IR, human heat energy 17. Heat dissipation: radiation, evaporation, conduction 18. Micrometeroid protection. Kevlar jackets for spacecraft! 19. Radiation shielding needed to protect humans and instruments Attitude and Trajectory Control. 20. Why is attitude control needed? Point antenna at Earth, for accurate on-board experiments, thermal control, propulsion maneuvers. 21. Geostationary orbit: good for communications satellites always over the same place on Earth. 22. Disadvantages of geosynchronus orbit: Orbit is high, expensive to boost there, higher radiation levels (Van Allen belt), greater transmission power is needed, signal transmission delay (« second round trip). 23. Earth Resources missions: mapping and measurement, exploration, management. 24. Technology advances in space: semiconductor cystrals for solid state circuits; protein cystals; space-resistant materials; computer improvements for hostil environments and versatile operations ; micro miniature circuits and components; communications systsems; aviation- related materials; aviation-related hardware; medical technology; statellite and spacecrft advances (communications, advanced power devices, and durable materials and coatings) 25. US space boosters with payload capacity to LEO in kg: Space shuttle 24,400; Atlas II 6,400 kg ; Titan IV 17,799; Delta 11 5,040 kg; Scout 270; Taurus 1,450; Pegasus 455 26. Russia space boosters: Proton 20,000; Soyuz 18,000; Zenit 17,700. 27. Space boosters, China: Long March 8,300 kg 28. French space boosters: Ariane 4 9,600 kg 29. Japan boosters: H1 3,200 kg 30. Astronomical research: mostly by observations of light in various wavelengths. Radio waves; IR-infrared ; visible band; UV ultraviolet; X-ray; Gamma ray; These are all forms of light, with radio the least energetic through gamma rays, the most energetic. 31. Navigation: Global Position System (GPS) 32. Geology: Mapping, surface observations; surface activity; modeling 33. Weather: Observation; forecasting; upper atmospheric research; modeling 34. Physics: Solar measurements; particle measurements; dynamical motion studes of complex objects in free-fall environment. 35. Microgravity: Crystal growth; Crystals are more uniform because of lack of stress; electrophoresis: separating porteins using an electric field, works better in space; protein crystal growth ordinarily very difficult, easier in space; semiconductor cyrstal improvements crystals are more uniform and pure; metal alloy research and production 36. Medical research: drug research and production; environmental research' radiation effects; heating and cooling systems; gravity effects on growth, aging health; long-term effect of microgravity environment on human body. Remote Sensing and Earth Exploration 37. Remote sensing is the observation of Earth (and distant celestial objects) from distant vantage points (high flying aircraft and space vehicles). 38. Remote sensing is carried out by instruments that record light in various wavelengths. These records are then analyzed. 39. Radio band: good for atmospheric measurements. 40. Microwave band: surface features, radio astronomy 41. Visible band: surface features 42. Infrared band: surface features 43. UV band: uper atmosphere measurements 44. X-ray band: observation of stars (including the sun) and galaxies 45. Gamma-ray band: energetic stars and galaxies 46. Remote sensing applications. Agriculture classify crops; assess condition; assess yield; map soil characteristics; map soil management practices; compliance monitoring. 47. Remote sensing applications: Forestry mapping, clear-cut mapping, forest inventory, deforestation evaluation, watershed evaluation, coastal forest protection. 48. Remote sensing applications Geology-----surface deposit mapping; sedimentary mapping; structural mapping; event mapping; mineral exploration; hydrocarbon exploration; environmental geology; geo-hazard mapping; planetary mapping 49. Remote sensing applications ice pack----changes in the icepack are important to understanding global and seasonal changes on Earth. 50. Hydrology study of the Earth's water cycle important to life and everything else on the planet. Radar is useful here, since it can even reach below the surface in dry conditions. Examples: Wetlands mapping and monitoring; Soil moisture estimation; snow pack evaluation; river and lake ice; Flood mapping and monitoring; Glacier dynamics; River delta changes; irrigation evaluation and monitoring 51. Applications of remote sensing: disaster planning and evaluation 52. Planetary observations. More specific examples of Remote Sensing Applications. 53. Chesapeake Bay coastal marshes, seafood industry and water wfowl and shorelines; California wine industry protection from insect infestation, improve crops; Crop yields and irrigation patterns in Kansas; Fire hazard assessments; pollution assessment; identification of dangerous brush fires; Ozone layer; better weather forecasting. 54. Ozone layer(O3) protects the biosphere from ultraviolet radiation, which causes cancer and also leads to blindness. There has been significant ozone loss. 55. Carbon buildup in the atmosphere could lead to global warming. Space Stations 56. Fiction by Ed Hale and Jules Verne involved space stations, then technical designs by Tsiolkovsky and Oberth. 57. First preliminary designs were by Wernher Von Braun, in the 50's, in Collier's magazine, a 250 ft diameter wheel made of structural nylon. 58. First US space station, Skylab in the 70's, from old Apollo hardware. 59. 1984 Soviet Mir launched, 2 man average capacity and 4 modules. Manned from 1986 to present nearly continuously. Launched by a Proton rocket. 60. 80's: Reagan supported a station, but it was constrained by the Shuttle payload bay. 61. 1991 Commitment to launch, single keel, six panel power system. US, Russia, Japan, Canada, and ESA to build International Space Station Alpha. Later shortened to ISS. 62. 1998 first module launched, by a proton rocket, Zaria, the russian propulsion and control module. Skylab 63. Launched by Saturn V, the Saturn-1B third stage module was converted to Skylab. Manned flights used Saturn 1B. 64. Three crews stayed on Skylab in 73-74, for 28, 59, and 84 days, respectively. Skylab reentered the atmosphere in 1979. 65. Experiments included solar observations in x-ray and gamma ray regions; material science research; Earth observation; weather, atmospheric and geological studies;; X-ray, gamma-ray, UV, IR, visible and radio frequency observations; animal life in zero-g; Space sickness; calcium and bone loss; structures and physics research. 66. Salyut-1: 1971. Salyut 2-5 1972; 6 1977;7--1982. 67. Mir: extension of Salyut. 68. Salyut was based on the Soyuz spacecraft. Three main compartments: a small cylinder, larger cylinder, and airlock/transfer module with docking adapter. 69. First mission to Salyut 1 a bust crew could not enter station. 70. Second mission ended in disaster when air leaked out of return vehicle, killing all cosmonauts. 71. Salyut 2: developed tumbling problem and broke up. 72. Salyut 3 June 24, 1974 first military space station. 73. Salyut 6 second generation station, 5 modules. Notice how small the modules are the biggest are a little over 2 meters long and four meters across. 74. Salyut 6 was first to use unmanned Progress cargo ferries. Class Notes: 75. Four kinds of orbits, known as conic sections: circular, elliptic, parabolic, and hyperbolic. 76. Hohmann transfers are the most efficient in terms of energy. 77. Transferring from one planet to the next is accomplished by firing the rocket engines tangent to the trajectory, turning a basically circular orbit into a long ellipse, with aphelion at the target planet, perihelion at the home planet (Earth, last time I checked). Same type of action for travel to an inner planet, but engines fired in the opposite direction.