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. In other words, innumerate POMA BS  . In other words, innumerate POMA BS
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 .147 "H bombs of the 50s gigantic" ... no, [ [https://www.britannica.com/technology/nuclear-weapon/The-Teller-Ulam-configuration | Castle Bravo in 1954 --> 20 tonnes 20MT ]]

wiki.keithl.com/KakuFuture

The Future of Humanity

Terraforming Marsm Interstellar Travel, Immortality, And Our Destiny Beyond Earth

Michio Kaku 2018, 629.455 KAKU Cedar Mill Library

The media-canonical future, as channeled by a 70yo pop-sci media gadfly and former theoretical physicist. Many acknowledgements of other non-engineer non-inventor non-entrepreneur media pundits. Much focus on "ick factor" reactionary barriers. I mostly skimmed the book, looking for any surprises.

  • p1 Prologue, Toba volcanic explosion 75 kya.
  • p5 Sun expansion to 1.2 AU 5Gy from now

  • p20 Tsiolkovsky aside

  • p21-23 Goddard, no mention of Roswell work

  • p25 3000 V-2s, 9000 Allies deaths, more slave labor deaths building them
  • p32 unnamed congressman "no buck rogers, no bucks" ... and no citation, perhaps POOMA.

  • p36-xx NASA SLS, Bezos moon, 6% B
  • p43 ice on moon
  • p47 "The astronauts would have to adjust to the lower gravity on the moon"
    • er, no, near-one-gee may be necessary for health, the Moon is 83% zero gee.
    • also ignores effects of abrasive lunar dust on equipment
  • p54 Mining the heavens - does not discuss deltaV, refining/reduction/processing
  • p60 Dawn asteroid mission orbiting Ceres since 2015 (hydrazine depleted 2018)

  • p62 Mars and Musk
  • p67 "failure rates still 1%, fatality rates 3.3%" ... per person, not per mission ... and none in 20 years, so this is not a rate, it is an average heavily biased by the accidents that ended the Silly Spaceplane era.
  • p68 problems with zero gee, loss of bone mass, optic damage
  • p69 Radiation cancer effects of Mars trip (3% increased cancer risk) compared to zero gee and failure risk
  • p70 2016 ... Scientists at UC Irvine ... mice large doses ... brain damage
    • no citation, google scholar couldn't find, could find similar work at Loma Linda university
  • p71 Deep Space Gateway "will act as refuelling and resupply station for missions to Mars and the asteroids"
    • no, DSG Lunar Gateway is for technology development and lunar exploration, and makes no sense for a Mars mission

    • Delta V from LEO to Mars Hohmann 13.7 km/s, delta V with with boost near Moon 17.1 km/s Delta V
    • stop at Gateway ???? but it will be still more total Delta V. Best to spew reaction mass deep in Earth's gravity well.
    • p74 Solar electric propulsion - maybe
  • p76 Mars the garden planet? No, Mars the dim toxic resourceless deep gravitational energy well, "60% zero gee" relative to healthy Earth gravity
  • p83-87 Zubrin
  • p92-93 Venus hellhole, dense CO₂, nonsense about gas baked out of rocks leading to 90 bar pressures, no citations
  • ...-p108 more stuff about the (in)habitability of other planetary moons.
  • p111 "Robots in space" ... random miscellany chapter: CNT, AI, robots, replicators, consciousness, paranoid movies
  • p137 Starship
  • 140 Laser sails: "5 seconds to Moon, 1.5 hours to Mars, a few days to Pluto", no citations, POMA?
    • accelerate for about two minutes
    • acceleration = 2 d / t^2 for 2 minutes:

destination

time (s)

distance (m)

avg velocity (m/s)

Moon

5

3.84e8

77e6 (0.25c !!)

Mars

5400

2.3e11

43e6 (0.14c)

Pluto

350000 (4d)

6e12

17e6 (0.06c)

more later

KakuFuture (last edited 2024-01-05 22:56:11 by KeithLofstrom)