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Compatibility Mode The Last Space Shuttle Mission July 8, 2011 QuickTime™ and a decompressor are needed to see this picture. Video: NASA Where Are We Going? • Low-Earth Orbit • Interplanetary Travel • Interstellar Travel Image: NASA Where Are We Going? • Low-Earth Orbit • Interplanetary Travel • Interstellar Travel Image: NASA Low-Earth Orbit Current Low-Earth Orbit capabilities: • International Space Station • Russian Soyuz • Chinese Shenzhou Images: NASA; Wikimedia (AAxanderr) NASA Partnerships Instead of building low-earth orbit spacecraft, NASA is partnering with private companies. NASA Partnerships Low-Earth Orbit capabilities in the works: Dragon Cygnus CST-100 (SpaceX, 2011) (Orbital, 2012?) (Boeing, 2015?) Images: SpaceX (used with permission); Orbital (via NASA); The Boeing Company (via NASA) Dragon • First launch and recovery December 8, 2010 • Demo mission to ISS planned for November 30, 2011 Image: SpaceX (used with permission) Low-Earth Orbit Outlook: • We’re already there! Image: NASA Low-Earth Orbit Outlook: • We’re already there! • Low-earth orbit travel will become cheaper and more accessible over the next decade. Image: NASA Where Are We Going? • Low-Earth Orbit • Interplanetary Travel • Interstellar Travel Image: NASA Interplanetary Travel Obama’s Projected Timeline: • 2010s: development of low- Earth orbit vehicles Image: NASA Interplanetary Travel Obama’s Projected Timeline: • 2010s: development of low- Earth orbit vehicles • 2025: crewed missions into deep space Image: NASA Interplanetary Travel Obama’s Projected Timeline: • 2010s: development of low- Earth orbit vehicles • 2025: crewed missions into deep space • 2030s: crewed missions to Mars and back Image: NASA In the News: Space Launch System NASA has announced designs for a new heavy-lift rocket to reach beyond low-earth orbit. Image: NASA In the News: Space Launch System • Horsepower equivalent of 160,000 Corvette engines • Weighs 5.5 million pounds, or the equivalent of 24 fully loaded 747s • Payload of 77 tons, or the equivalent of 12 full-grown elephants Image: NASA Challenges • Propulsion • Radiation exposure Challenges • Propulsion • Radiation exposure Limitations of Chemical Propellants Remember from Part I: 2 H2 + O2 → 2 H2O(g) + Energy Limitations of Chemical Propellants Remember from Part I: 2 H2 + O2 → 2 H2O(g) + Energy How much energy? 1 lb H2 7.5 days Image: Wikimedia (Inductiveload) Limitations of Chemical Propellants Remember from Part I: 2 H2 + O2 → 2 H2O(g) + Energy Space Shuttle external tank carried over 200,000 pounds! Limitations of Chemical Propellants Remember from Part I: Moon 384,403km 1x 8.5 hr Mars 74,799,000km 195x 6 mo Jupiter 893,000,000km 2,323x 13 mo Solar System 4,338,342,000km 11,286x 8 yr Proxima Centauri 42,000,000,000,000km 109,260,000x 78,000yr Limitations of Chemical Propellants “About two-thirds of the mass on an Earth- to-Mars-to-Earth mission would be propellant” - Review of Human Spaceflight Plans Committee Final Report, October 2009 Alternatives to Chemical Propellants Chemical reactions: same atoms, new molecules 2 H2 + O2 → 2 H2O(g) + Energy + → + Alternatives to Chemical Propellants Chemical reactions: same atoms, new molecules 2 H2 + O2 → 2 H2O(g) + Energy + → + Nuclear reactions: new atoms 2 H2 → He + Energy → + Alternatives to Chemical Propellants Chemical reactions: same atoms, new molecules 2 H2 + O2 → 2 H2O(g) + Energy + → + Nuclear reactions: new atoms 2 H2 → He + Energy → + 400,000 x more energy Alternatives to Chemical Propellants Chemical reactions: same atoms, new molecules 1 lb H2 7.5 days Image: Wikimedia (Inductiveload) Alternatives to Chemical Propellants Chemical reactions: same atoms, new molecules 1 lb H2 7.5 days Nuclear reactions: new atoms 1 lb H2 2,900 years! Image: Wikimedia (Inductiveload) Propulsion “If we ever really want to explore the solar system, it’s going to have to be nuclear” - John Grunsfeld, PhD, former astronaut Quote: AAAS “NASA at a Turning Point” http://membercentral.aaas.org Challenges • Propulsion • Radiation exposure Radiation Exposure On Earth we are protected by: • Earth’s magnetic field Image: NASA Radiation Exposure On Earth we are protected by: • Earth’s magnetic field • The atmosphere Images: NASA; NASA/Goddard Space Flight Center Conceptual Image Lab Radiation Exposure Space station crew receives the equivalent of about 1 chest X-ray every 1-2 days. Images: NASA; Wikimedia (Nevit Dilmen) Radiation Exposure Interplanetary astronauts will be outside the Earth’s magnetic field and need protection from radiation. But radiation shields are heavy! Images NASA Interplanetary Travel Outlook: The technological hurdles are probably surmountable… Image: NASA Interplanetary Travel Outlook: The technological hurdles are probably surmountable… … but will require long-term investment and research. Image: NASA Where Are We Going? • Low-Earth Orbit • Interplanetary Travel • Interstellar Travel Image: NASA, ESA, and the Hubble Heritage Team; A. Riess (STScI) In the News: 100 Year Starship A DARPA program to develop a research and investment model that may one day allow us to build a starship Image: NASA In the News: 100 Year Starship NOT a program to build a starship! Image: NASA In the News: 100 Year Starship On 11/11/11, DARPA will award $500,000 to study what it will take to launch a starship 100 years from now. Image: NASA Interstellar Travel 100 years isn’t so crazy: Jules Verne published “From the Earth to the Moon” in 1865, 104 years before the Apollo landings. Images: Wikimedia; NASA Interstellar Travel Outlook: If it happens, it is unlikely to be in our lifetimes… Image: NASA, ESA, and the Hubble Heritage Team; A. Riess (STScI) Interstellar Travel Outlook: If it happens, it is unlikely to be in our lifetimes… … but clever people are starting to think about it! Image: NASA, ESA, and the Hubble Heritage Team; A. Riess (STScI) Where Are We Going? QuickTime™ and a decompressor are needed to see this picture. We are ready at last to set sail for the stars. ~ Carl Sagan Video: NASA Toward the Final Frontier of Manned Space Flight Part I: How we got here: Background and challenges (Ryann) Part II: Why boldly go? Why not? (Luke) Part III: Where are we going? (Emily) Thank you! SITN would like to acknowledge the following organizations for their generous support. Harvard Medical School Office of Communications and External Relations Division of Medical Sciences The Harvard Graduate School of Arts and Sciences (GSAS) The Harvard Biomedical Graduate Students Organization (BGSO) The Harvard/MIT COOP Restaurant Associates.
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