Recent content by Fred Bobo

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    Undergrad Heating/cooling moon tunnels, why and how?

    heat pump lines toward the center, not the surface.
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    Undergrad Heating/cooling moon tunnels, why and how?

    No. And yeah.
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    Undergrad Heating/cooling moon tunnels, why and how?

    That is my question.
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    Undergrad Heating/cooling moon tunnels, why and how?

    Read a story in the Analog, April 1990, issue. The author describes a cooling system for moon tunnels using water that is cooled via large fins on the surface. An explanation is given that rock is a poor conductor of heat and eventually equalizes. And therefore the need for cooling. Why would...
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    Undergrad Orbital velocity of a craft at 4km above the Moon's surface

    Thank you. All good now.
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    Undergrad Orbital velocity of a craft at 4km above the Moon's surface

    Thank you. But i am at a loss. https://en.wikipedia.org/wiki/Gravitational_constant gives me all kinds of variations for G. You got some suggestions about what G value/formula i should use for your formula?
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    Undergrad Orbital velocity of a craft at 4km above the Moon's surface

    Thank you.
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    Undergrad Orbital velocity of a craft at 4km above the Moon's surface

    What would be the orbital velocity of craft at 4km above moon surface? Assume a mass of 1,000,000 lb, US.
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    Writing: Input Wanted Duration: flights to L-4 point, and 90 degrees Earth orbit

    Thank you. more to think about.
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    Writing: Input Wanted Duration: flights to L-4 point, and 90 degrees Earth orbit

    Also: what do think the minimum acceleration should be to maintain human body health? I think long hauls will be best to be at 1g. Shorter trips, even repeated often, will be less injurious. Or else not.
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    Writing: Input Wanted Duration: flights to L-4 point, and 90 degrees Earth orbit

    Thank you. would there not be a period of ramp up that will not exist at the end? Trying to visual. ========= how about L1-3 and the moon for a craft 1/10-20th the size? Daily/hourly transports to the destinations within a 24 hour duration. ================ I really wish i knew how to...
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    Writing: Input Wanted Duration: flights to L-4 point, and 90 degrees Earth orbit

    Assumptions: 200+ years from now Asteroids have been moved to all Lagrange points, and at least 90, 180, and 270 degrees on Earth's' orbit for mining, and shielding humans and equipment Tech to acceleration/decelerate at 1 gravity without need to carry fuel. (My main fiction.) Direct line of...
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    Writing: Input Wanted What is the fastest route to Earth 180

    Thank you all for your responses.
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    Writing: Input Wanted What is the fastest route to Earth 180

    Let us assume there is a large space array at 180. And docking is the goal. Why go forward? Meanwhile, back at the ranch: what can be the acceleration generation from a solar sail? Size related to payload. Over what period?
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    Writing: Input Wanted What is the fastest route to Earth 180

    Scenario: Large satellite arrays are at 90, 180, 270 degrees of Earth's orbit What is the fastest route to Earth 180? Possible fuels: liquid, solid, ion, sail, gravity The best route? Forward / backward ? Thrust when, from? Talk to me