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| . no, different, but easier with proper infrastructure. Earth escape energy is 63 MJ/kg, lunar escape velocity energy is 2.8 MJ/kg ... 22 times less energy to dissipate, with no atmosphere to constrain the solution. An "inverse launch loop" track could shed that lunar arrival kinetic energy in d=E/a distance; for acceleration a=20 m/s², d=140 km, time =. Decelerating a few incoming vehicles wouldn't pay for the track, but one per minute is half a million per year. . In detail, a Hohmann transfer orbit ellipse from Earth radius perigee 6500 km (122 km equatorial altitude) to lunar orbit radius apogee ( r = 385000 km equatorial altitude). Estimate perigee launch velocity as approximately Earth escape velocity 11.2 km/s; from conservation of angular momentum the apogee velocity is approximately (6500 km / 385000 km )*11200 m/s ≈ 190 m/s . That is not much energy difference compared to lunar escape energy. | . no, different, but easier with proper infrastructure. Earth escape energy is 63 MJ/kg, lunar escape velocity energy is 2.8 MJ/kg ... 22 times less energy to dissipate, with no atmosphere to constrain the solution. An "inverse launch loop" track could shed that lunar arrival kinetic energy in d=E/a distance; for acceleration a=20 m/s², d=140 km, time =. Decelerating a few incoming vehicles wouldn't pay for the track, but one per minute is half a million per year. . . . . . . In detail, a Hohmann transfer orbit ellipse from Earth radius perigee 6500 km (122 km equatorial altitude) to lunar orbit radius apogee ( r = 385000 km equatorial altitude). Estimate perigee launch velocity as approximately Earth escape velocity 11.2 km/s; from conservation of angular momentum the apogee velocity is approximately (6500 km / 385000 km )*11200 m/s ≈ 190 m/s . That is not much energy difference compared to lunar escape energy. |
Rocket Dreams
Musk, Bezos, and the Inside Story of the New, Trillion Dollar Space Race
Christian Davenport . Multco . 919.904 D2471r . 2025
- p001 Introduction
Part I: Earth, 2016-2018
p011 Ch.01 - "I Get This Angry Twice in a Year"
- p011 2017 March 1 Oscar - Manchester by the Sea
- p012 "study hall", 6 page document, 30 minutes reading
p014 Moon not cold dead rock, instead potential oasis, water in shadowed south pole craters
wp hydrates, est. 10 to 1000 ppm, 2025 PRIME-1 mission
- actually IM-2 mission, PRIME-1 payload of a drill and mass spectrometer ... failed landing, no useful data
p015 Pence National Space Council
p017 Shenzhou "Divine" capsule
p017 Shenzhou 5 mission claimed flawless, actually injurous gees
- p017 cleanup, fake second hatch opening
p018 Chang'e-1 mapped lunar surface
p018 Chang'e 3 lander 2023/12
- p023 Musk wanted for NASA Mars plan
- p025 Bezos wanted NASA Moon plan
p026 Ch.02 - Elon's Real Superpower
- p026 Musk taunts Bezos, Blue Origin not moving fast enough
- uh ... Gradatim Ferociter
- p026 2013 SpaceX granted right to lease Launch Complex 39A
- p027 Musk mantra focus on customers, not competitors
- yet it seems Davenport focuses on a "competition" with SpaceX already the winner
- p027 Amazon "Get Big Fast", compares 2016 Blue Origin 700 to (NASA funded) SpaceX with 5500
- p028 Blue Origin before 2016 bid as subcontractor, "from now go after SpaceX bids"
p029 Charles Miller "What can you do relative to the moon by 2020?"
p029 Brett Alexander
- p029 "Landing on the moon was far more difficult than landing on Earth"
- no, different, but easier with proper infrastructure. Earth escape energy is 63 MJ/kg, lunar escape velocity energy is 2.8 MJ/kg ... 22 times less energy to dissipate, with no atmosphere to constrain the solution. An "inverse launch loop" track could shed that lunar arrival kinetic energy in d=E/a distance; for acceleration a=20 m/s², d=140 km, time =. Decelerating a few incoming vehicles wouldn't pay for the track, but one per minute is half a million per year. . . . . . . In detail, a Hohmann transfer orbit ellipse from Earth radius perigee 6500 km (122 km equatorial altitude) to lunar orbit radius apogee ( r = 385000 km equatorial altitude). Estimate perigee launch velocity as approximately Earth escape velocity 11.2 km/s; from conservation of angular momentum the apogee velocity is approximately (6500 km / 385000 km )*11200 m/s ≈ 190 m/s . That is not much energy difference compared to lunar escape energy.
p038 Ch.03 - Converting the Impossible to Late
p054 Ch.04 - On a Jihad
p070 Ch.05 - The Dark Side of Space
p083 Ch.06 - "I'll Say You're Fired in Two Minutes"
Part II: Earth Orbit, 2018-2020
p101 Ch.07 - Starman
p113 Ch.08 - Flying by Swipe
p128 Ch.09 - Question Everything
p144 Ch.10 - By Amy Means Necessary
p160 Ch.11 - Artemis
p177 Ch.12 - "We Just Blew It to Smithereens"
p195 Ch.13 - "Thank You for Flying SpaceX"
Part III: Beyond, 2020-2025
p215 Ch.14 - Super Hardcore
p231 Ch.15 - A Chinese Flag in the Lunar Soil
p246 Ch.16 - Can't Get it Up (to Orbit)
p265 Ch.17 - The Gremlins of Unknown Unknowns
p279 Ch.18 - Toxic, Limping, Abysmal
p296 Ch.19 - Corporate Alchemy
p319 Epilogue - Plant the Flag