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   .p188 "Musk cofounded !PayPal ..." nope. Thiel, Levchin and others. Musk was !XPay competitor, merged later.
  . Red Dragon. Multiplanet species? How can we survive on Mars without some Earth technology?
 .p190 Axel Rover, tethered pair to traverse steep terrain. khl: snagged tether?
 .p190 Aerial Regional-scale Environmental Survey of Mars, [[ https://en.wikipedia.org/wiki/Aerial_Regional-scale_Environmental_Survey | ARES ]] robot aircraft
  .khl Highly unlikely. [[ https://nssdc.gsfc.nasa.gov/planetary/factsheet/marsfact.html | Mars surface density ]] = 20 g/m³ similar to Earth at 28 km altitude, gravity . This would not be an airbreather, nothing to burn in the CO₂ atmosphere. The solar powered (18.5 kW), 2300 kg, 75 meter wingspan [[ https://en.wikipedia.org/wiki/Helios_Prototype | Helios UAV ]] briefly flew as high as 29,524 m off Kauai (22° N), presumably under full 1360 W/m² illumination. Mars insolation at 1.524 AU is 43% of Earth, gravity 38% of Earth. Probably not enough power, and no runways to land at night.
 .p191 Tracing Habitability, Organics, and Resources THOR (impact penetrators, orbital observation)
 .p191 Nuclear-powered compressed CO₂ jet "hoppers"
 .p192 Mars Atmosphere and Volatile EvolutioN (MAVEN) orbiter. Entered Mars Orbit 22 September 2014.
 .p193 [[ https://en.wikipedia.org/wiki/InSight | Mars InSight]] lander, currently scheduled for 26 November 2018 landing near Elysium Planitia at the equator, to study the planetary core of Mars via the SEIS seismic sensor, the HP3 heat flow probe ("as deep as 5 meters"), and the RISE (Rotation and Interior Structure Experiment) to precisely measure rotation.
 .p197 Cyclers - 6 months to Mars on "up" cycler, 6 months back on "down" cycler, 20 months on return journey.
 .p198 6 km/s at Earth, 10 km/s at Mars p199 other versions have much lower flyby velocities

Buzz Aldrin Books


Mission to Mars

MY VISION for SPACE EXPLORATION

With Leonard David, National Geographic Books, Multnomah County Central Library, 629.4553 A3658m 2013


MoreLater, still pondering this book

Dr. Aldrin wants humans to explore Mars. His approach is more rational than most, beginning with teleoperation of robots from Phobos. The mid-term goal still seems to be a permanent and self-sustaining human settlements (p181). Given that it took 4 billion years for evolution to produce our "better of most possible worlds", and a vast interconnected global economy to send a tiny amount of hardware into space (so far), it is difficult to conceive of how a second survivable world can be created on inhospitable Mars.

His timeline for the buildup to this starts before the book was written, after a meeting with President Obama in 2010. Obama's speech saying "by 2025, we expect new spacecraft designed for long journeys ...". In 2017, as I write this, the politician's claims remain grandiose but the progress tiny. Such developments require far more time than a US presidential administration, and every new administration arrives with new speeches and new campaign contributors to fund. Reset the clock, choose different goals, make bigger claims than predecessors, spend more, accomplish little.

Aldrin is correct that a second manned race to the Moon is a waste of time and money. But the Moon is valuable for many kinds of research, and economic development. Throughout history, exploration was soon followed by economic exploitation. If we skip the exploitation part, what justifies the continuing expenditure? The great explorations of the past were driven by profit and power.

On page 20, Aldrin calls for a reusable booster - !SpaceX reused a booster early in 2017, and we will find out how that actually affects the bottom line when Elon Musk runs out of rich folks willing to invest without dividends. Musk seemingly claims he will go to Mars in his Dragon capsule, but even Aldrin's cyclers may be too cramped for this very long journey.

Aldrin hopes for cyclers in 2029, a Phobos visit in 2033 (last color plate) ... starting with a Constellation replacement in 2010. Didn't happen, restart the clock 7 years later. If we have any sort of orbital crew vehicle by the end of 2017, and the cadence of this illustration holds, we might reach the orbit of Mars in 2040, and travel to the surface and back years later, when Musk is in his 70s. Musk may make a attempt to Mars decades sooner, but unless there are miraculous biological advances soon, he will die in the attempt.

Aldrin's schedule is ambitious as well; Mars is 1000 times further away, and the journey will take 70 times as long as Apollo. We will need a lot of capability in place to support the eventual arrival of humans. Phobos is a good first goal; the delta V to Mars surface and back is around 9 km/s, a significant fraction of an Earth/Moon mission with no Mars-local infrastructure to support it.

The best idea in the book is synchronous cyclers, space habitats with shielding and infrastructure to support astronauts between Earth and Mars orbit. The cyclers will still need to be supplied with consumables and propellant, ditto for the Mars outpost at the other end. They will also require "escape velocity plus" delta V to reach at both ends, plus additional thrust on the cycler itself to keep it in an orbit that synchonizes with both Earth and Mars.

I don't expect Dr. Aldrin to agree, but launch loops capable of putting megatons into high orbit would be a good way to assemble a cycler and launch it into its interplanetary cycle, and would have enough delta V to supply a cycler directly as it flies by near Earth. A 5 tonne launch loop could make many launches towards the steadily changing position and velocity of the cycler, with many chances for error ... or cumulative success, assembling kilotonnes of components for cyclers. In time, experience and automation will reduce those errors.


  • How much? Gathering material to build a cycler will require many 5 tonne launches from multiple loops. If the sum of the launches are spaced 20 seconds apart, and leave Earth at 2.5 km/s, then the components are spaced 50 km apart. If the cycler assembles over 4 months (10 million seconds) on the way to Mars, and we allow up to 500 m/s delta V to advance or retard each component compared to the whole, AND (handwaving warning!) the 24 hour turn of the launch loop perigee can be accomodated somehow, then we can "close up" this constellation of components over a distance of 5 million kilometers to each side. That is 1e7/50 times 5 tonnes or 1 million tonnes.
  • This is probably WAY too optimistic - the Earth does indeed turn, and so the "launch window per day" may be 10% of the whole, and other problems may add another factor of 10; we might have only 10,000 tonnes to work with. Much of that will be propellant, which with proper design will double as shielding. So will food, and so will the excrement made from that food.

---

Page 154-157 of the book discusses telepresence in hopeful words. Me mentions UT Austin astronomer Dan Lester as a champion of exploration telepresence, and S. Fred Singer as an advocate of surface landers controlled from Phobos or Diemos via relay satellites. From Phobos, I figure that to be a 39000 km, 130 millisecond round trip, as opposed to a 0.7 hour round trip from Earth; an excellent opportunity for telepresence. If we develop 2.7 second predictive-adaptive telepresence from Earth to Moon, and 50 millisecond lunar orbit-to-surface telepresence, we will have excellent tools to do this.

Namedrops

  • p002 Ares/Constellation, Altair lander
  • p019 Sierra Nevada Dream Chaser
  • p021 Starcraft Boosters, Hubert Davis, flyback booster
  • p023 Orion spacecraft by Lockheed-Martin, mostly disposable, Aldrin:-(
  • p029 Unified Space Vision p31 human presence on Mars by 2035
  • p032 launch Orion on Delta IV, cancel Ares
  • p034 early sketch of Aldrin cycler - James Longuski Purdue, Damon Landau JPL
  • p037 Aldrin XM, exploration module, up to 3 years p38 2018 one year flyby of 46P/Wirtanen
  • p038 2019/20 2001 GP2, 2021 99942 Apophis (250m, possible 2036 impact, 2029 diversion mission)
  • p041 Buzz Basics: Aerocapture, Radiation Protection, Closed Loop Life Support
  • p046 United Strategic Space Enterprise think tank, ShareSpace raffle, International Space University, Bigelow Aerospace inflatables

  • p051 Space tourism, p54 Zero Gravity Corporation parabola flights
  • p063 Bigelow inflatible 2100 m³, 2x ISS
    • khl: if ISS is 1050 m³, typical crew of 6, that is 175 m³ per astronaut
    • khl: "Space Ship Earth" is 5.1e14 m², 7.38 billion people, scale height 8500 meters, so that is 5.9e8 m³ per person. If we limit "Earth Space" to moderately inhabited land (10% WAG) and 3 meters vertically, that is 2e4 m³ per person. My (underpopulated) house, including basement business/lab/library, is 320 m³ per inhabitant. So, space station is as crowded as a family home, but vastly smaller than the biosphere that surrounds all family homes, per inhabitant. How much volume do people need to survive long term? Biosphere 2 was 2.5e4 m³ per inhabitant, and lethally inadequate to support them. Some (who have never built a closed environment) believe they can do a better job.
    • khl: BEAM, Bigelow Expandable Activity Module 16 m³ berthed to space station 2016/04/16, unberth 2018
  • p065 Spaceport America in New Mexico, $209 million of state money ending 2013/12. (Currently running with a $0.5M deficit).
  • p068 SRV suborbital reusable vehicle, 8000 interested passengers, 925 with reservations (Tauri Group)
  • p069 other suborbitals: Armadillo Aerospace, Blue Origin (Bezos), XCOR Aerospace Lynx 2 crew suborbital
  • p070 Boeing CST-100 commercial (7) crew vehicle, Masten Space Systems (?), Orbital Sciences Cygnus (cargo), Sierra Nevada Dream Chaser (Atlas launcher)
  • p075 2011: 84 launches ( Russia 31, China 19, US 18 )994 active satellites, 70% of NASA workforce between 40 and 60
  • p076-78 October 2012 Dragon to ISS
  • p081-093, Apollo
  • p094 Inernational Lunar Development Authority, International Lunar Research Base
  • p095 Pacific International Space Center for Exploration Systems
    • p096 Telerobotics (from habitat at "lagrange point" ... L1? )
  • p098 E-M L2, Earth visible?? 0.4931 R, yes (some online sources wrong)

  • p101 need 4 or 5 lunar navigation satellites
  • p105 US Antarctic mission 1600 staff. Chandrayaan-1 2008, LCROSS 2009
  • p106 Shackleton Crater lunar south pole, 12 miles wide 2 miles deep; Malapert Mountain 45 km away, continuously visible from Earth
  • p108 Paul Spudis Lunar and Planetary Institute Houston, 600 Mtonne ice at lunar north pole
  • p109 Harrison Schmitt and Dennis Wingo (Skycorp @Moffitt) extract He3 for fusion
    • :-( what percentage of EARTH Helium is He₃? Why is lunar He₃ easier to extract? How much equipment?

  • p110 Alex Ignatiev, Alexandre Freundlich Center for Advanced Materials University of Houston: make solar cells
  • p112 David Criswell, solar power stations built on the Moon to beam microwave power to Earth :-( :-( Diffraction limit? WTF???

  • p118 2009 HC and 2000 SG344, NASA says accessable NEOs
  • p123 Elisabeta Pierazzo, Planetary Science Institute Tucson, 1 km midocean strike makes ozone destructive compounds ( :-( horizontal transport?)

  • p124 B612 Rusty Schweikert Sentinel NEO finder
  • p126 Russians want transmitter (transponder?) on 99942 Apophis
  • p130 6 month NEO mission Plymouth Rock in Orion, planner Josh Hopkins

  • p132 Target NEO: Open Global Community NEO Workshop July 2011

  • p136 bring backa 500 tonne asteroid for study in Earth orbit
  • p137 NASA OSIRIS-REx launched to 101955 Bennu (was 1999 RQ36, Carbonaceous, ≈ 7e10 kg, 250 meter radius ) on 8 September 2016

    • rendezvous August 2018, Depart March 2021, 0.1 to 2 kg sample return landing 24 September 2023
    • khl NASA impact table

  • p139 Jim Keravala Shackleton Energy Company p139 Dale Boucher Sudbury
  • p140 Chris Lewicki, Planetary Resources in Seattle
  • p141 floating troves ... uh, really? Beneficiation?

  • p146 Phobos 27 km diameter 16170 km orbit, Deimos 7 km diameter 30230 km orbit
  • color plate: Mars Cycler

    • pairs of: Solar Electric Propulsion (SEP), Node (with docking ports), Deep Space Habitat (DSH), Crew Vehicles 40 meters long
  • p151 An Yin UCLA, two tectonic plates, Aldrin extrapolates to landslides and Mars-quakes. There are plenty of hazards on Mars, but these probably ended billions of years ago.
  • p154 Curiosity and Telepresence: round trip control loop 8 to 44 minutes, 1.5 inches per second.
  • p156 Dan Lester see above
  • p158 Lockheed Martin, project Red Rocks on Deimos, using Orion. 10 months sunlight during Martian "summer".
    • khl Why not Phobos? Why not relocate to other Deimos pole during Martian "winter"? A 20 km drive, or a 4 m/s "orbital hop"
  • p160 Pascal Lee, Mars Institude, Haughton-Mars project at Ames, Phobos as "quarantine isolation" between humans and Mars surface
  • p162 Jay Melosh 2012: if Mars recently had life, some is in impact debris on Phobos
  • p166 permanent presence on Mars
  • p174 ISRU in situ resource utilization: methane, magnesium, perchlorates, sulfur, water, oxygen, silicon, metals
    • khl how much massive equipment is needed to concentrate and transform this mass into more equipment? What is the "feedback gain?"
  • p176 Autonomous and highly robust equipment is necessary khl: Autonomous == complex earth-sourced electronics, robust == heavy and/or repairable with spares

  • p178 people spread microbes and contamination, isolate them from study areas
  • p179 Ames Mars researchers Chris McKay and Carol Stoker, SETI Institute Robert Haberle and Dale Andersen, first base in Coprates Quadrangle region

  • p180 Mars base built mostly with local materials, Bruce Mackenzie Mars Foundation
  • p188 "Musk cofounded PayPal ..." nope. Thiel, Levchin and others. Musk was !XPay competitor, merged later.

    • Red Dragon. Multiplanet species? How can we survive on Mars without some Earth technology?
  • p190 Axel Rover, tethered pair to traverse steep terrain. khl: snagged tether?
  • p190 Aerial Regional-scale Environmental Survey of Mars, ARES robot aircraft

    • khl Highly unlikely. Mars surface density = 20 g/m³ similar to Earth at 28 km altitude, gravity . This would not be an airbreather, nothing to burn in the CO₂ atmosphere. The solar powered (18.5 kW), 2300 kg, 75 meter wingspan Helios UAV briefly flew as high as 29,524 m off Kauai (22° N), presumably under full 1360 W/m² illumination. Mars insolation at 1.524 AU is 43% of Earth, gravity 38% of Earth. Probably not enough power, and no runways to land at night.

  • p191 Tracing Habitability, Organics, and Resources THOR (impact penetrators, orbital observation)
  • p191 Nuclear-powered compressed CO₂ jet "hoppers"
  • p192 Mars Atmosphere and Volatile EvolutioN (MAVEN) orbiter. Entered Mars Orbit 22 September 2014.
  • p193 Mars InSight lander, currently scheduled for 26 November 2018 landing near Elysium Planitia at the equator, to study the planetary core of Mars via the SEIS seismic sensor, the HP3 heat flow probe ("as deep as 5 meters"), and the RISE (Rotation and Interior Structure Experiment) to precisely measure rotation.

  • p197 Cyclers - 6 months to Mars on "up" cycler, 6 months back on "down" cycler, 20 months on return journey.
  • p198 6 km/s at Earth, 10 km/s at Mars p199 other versions have much lower flyby velocities

BuzzAldrin (last edited 2020-06-08 00:11:26 by KeithLofstrom)