New Mars Forums

The Left's Macro-Cult: Recruited to Fight a Make-Believe War

Cast basalt's tensile strength is 30-40MPa, roughly half that of any variety of oak wood.  While it doesn't absorb water at all and is highly resistant to most acids and bases, which is great for chemical processing and brine transport, it's not particularly fond of large thermal shocks or very cold temperatures or impact loading.  Those drawbacks may mean very little for this application or they might become stumbling blocks on Mars since we're operating outside of the normal environmental extremes encountered on Earth.  Here on Earth steel mills frequently use cast basalt as a liner for chemical processing piping and waste stream removal.  Some sewers and runoff systems also use basalt liners.

Basalt can be cast or carved into plates / bowls / coffee mugs, too:

Mexico makes their traditional molcajetes from hand-carved basalt.

I've seen sinks / wash basins, bathtubs, and various decorative pieces carved from basalt as well.  Presumably, all tile flooring, sinks / tubs / toilets / shower stalls / drain pipes for bathrooms and kitchens, and most types of ceramic kitchenware could be made from cast basalt.

For structural applications, are there examples where cast basalt was selected for use here on Earth, just to show that it can be done and has been done before?

How might we improve upon basalt's tensile strength and other mechanical properties to something approaching a plain Carbon steel, if that's possible to do?

Could we add small amounts of Carbon Fiber to greatly enhance tensile strength?

We'd be processing the materials in an Oxygen-free near-vacuum atmosphere.

If that's not possible, can internally pressurized structures be kept in near-uniform compression using externally-applied loads, and how difficult is this to do in practice?

It seems as if that requires very careful engineering and construction, like weighing-out the overburden used to bury a basalt structure to guarantee the applied load matches the engineering calculations.  How generous are the "fudge factors"?  Maybe we can carve tunnels into bedrock and then use cast basalt tiles as abrasion and chemically resistant liners?  That would mimic how we already use cast basalt as pipe liners here on Earth.

You have to heat up the basalt, and presumably the mold, to around 1,300C to pour it like liquid Iron.  I don't know how fast you can cool molded basalt without cracking.  Pure Iron melts at 1,538C.  Inconel and stainless start to melt at temperatures remarkably similar to basalt.  They retain much more of their room temperature strength at higher temperatures than plain Carbon steels, but their alloy content, which reduces high temperature oxidation, actually depresses their melting points.  That's not a major difference in melting temperature between basalt and Iron, even though you also have to source coking coal or Hydrogen to make steel.  I can see how sourcing other materials to make steel would easily consume a huge amount of energy, though.  Steelmaking on Mars could end up being far more energy-intensive than it is here on Earth, so there's sound engineering and economic logic behind choosing a construction material with fewer processing steps and energy inputs.  The actual energy savings may be more modest than Earth-based energy input averages would suggest, though, and it's likely to be the case that making any bulk construction material on Mars is energy intensive.

If we have to make cast basalt structures thicker and therefore heavier to approximate the tensile strength values of steels, then how much energy do we save?

Is the entire logistical tail required to make cast basalt easier to acquire and use for structural applications?

Either way, we're starting from scratch here.  We obviously wouldn't be welding or cutting as much, nor splitting water to source Hydrogen to make steel, but we might need quite a few molds for all the castings (standardization is obviously key here), grinding and polishing to exact dimensions, adhesives with special properties to work in extreme cold to seal the structure, and specialized construction techniques to support above-ground structures before internal pressure can be applied.

Steel has been a staple of construction for the past two centuries, but that's because we have easy access to the energy inputs to mass produce it here on Earth.  Perhaps a modern Mars civilization will be built with stone instead of steel.

tahanson43206,

This document from Idaho National Laboratory describes XNR-2000's conceptual design:
Conceptual Design of a CERMET NTR Fission Core Using Multiphysics Modeling Techniques

It describes materials that were actually tested and proven to survive 3,000K temperatures while exposed to hot flowing Hydrogen.  The total Hydrogen mass flow rate required to achieve a 25,000lbf thrust level, with an Isp of 950s using 512MWth of reactor power output, was 12.05kg/s.  At the exhaust temperature / velocity associated with a 950s Isp, we'd therefore need 45,150,618Wth of input power per 1,000kg-f.

Edit:

This idea that the core heating length needs to be kilometers long is completely bogus.  I have no clue where it comes from.

Let's tally the total coolant flow channel volume.

0.1778cm^2 * pi * 90.69cm = 9.006847cm^3
9.006847cm^3 * 37 channels per fuel element = 333.253339cm^3
333.253339cm^3 * 151 fuel elements = 50,321.254189cm^3 (about 0.05m^3)
50,321.254189cm^3 / 12.05kg/s = 4,176.037692cm^3 per 1kg/s
The above is not exact since there's a power density difference in different core regions, but it's close enough.

50,321.254189cm^3 / 512MWth = 98.2837cm^3 to transfer 1MWth

1kg/s produces 941.064kg-f, so 1.063kg/s produces 1,000kg-f at 950s.

Let's say we did use a singular tube to transfer core thermal power, for whatever good that would do for us:
151 fuel rods * 37 coolant channels per fuel rod * 90.69cm core length = 506,685.03cm
506,685.03cm / 12 = 42,223.7525cm = 422.237525m

If we had a mere 37 individual coolant channels to mimic a single fuel rod, then the length of each heat transfer tube is 11.412m.  Presumably, we can manage a heat transfer tube length of 1m with 422 heat transfer tubes.  If each tube was "touching", then the width of a planar heat transfer device is only 150cm across.  Obviously we'd need spacing between tubes to contain the pressurized Hydrogen, but it's pretty easy to determine that a planar device with 422X 1m length heat transfer tubes is far less than 1m in width.  If the thickness of this "hot plate" was 2X that of the tube diameter, then it's only 7.112mm thick.  The device could be made from Tungsten and its total mass still wouldn't matter all that much to the performance of this low-thrust vehicle.

If we had a "hollow cylinder" (aka, "a pipe") device with a bunch of heat transfer pipes drilled through the pipe wall, with a gas manifold on each end, somewhat similar in external appearance to a NTR reactor core, but with a big empty space where the reactor fuel would normally go, then we ought to arrive at a mass / volume / length remarkably similar to an "empty" NTR reactor core (since our heat is being applied externally by concentrated sunlight, rather than generated internally through fissioning Uranium).

tahanson43206,

Assuming I did this correctly, which I may not have since it's been about 20 years since I took trig...

For a 200:1 expansion ratio, given Athroat = 2.5cm^2 Athroat, then Aexit = 500cm^2.

r = sqrt(A/pi)
sqrt(2.5cm^2/pi) = ~1.772cm
sqrt(500cm^2/pi) = ~12.616cm

GW said keep the nozzle wall angle between 12 and 15 degrees to minimize erosion, so I'm going with 15 degrees:
base * tan(90-15) = height
12.616 * tan(75) = 47.084cm
1.772 * tan(75) = 6.613cm
47.084cm - 6.613cm = 40.471cm = height of the frustum (nozzle length)

Anyone who wants to analyze a nozzle design can do so using the 3 software packages from the links I provided in my prior post in this thread, but you will need to know some design fundamentals- terminology, the basic equations involved in nozzle design, some gas and combustion kinetic fundamentals applicable to chemical rocket engines, etc.

I realize that our particular design problem only involves Hydrogen as a monopropellant used to produce NTR-like Isp using photonic power from the Sun, yet nearly all of the fundamentals still apply.  Combustion kinetics won't apply since this engine does not use combustion to generate heat, but still useful for general understanding of liquid rocket engine nozzle design.  GW can tell you if there are any major differences in solid vs liquid nozzle design considerations, but I think combustion kinetics would affect the design differently since combustion begins inside a rather lengthy motor casing and propellant grain geometry differences greatly affect reaction rates and thrust.

As a monopropellant, Hydrogen has some unique thermal properties and at the temperatures involved, hot flowing Hydrogen would cause a severe chemical attack against certain kinds of materials, especially metals, but the materials I specified are known to be resistant to that attack from the work NASA performed for the ROVER / NERVA Nuclear Thermal Rocket engine programs.  Specifically, Hydrogen has the highest heat capacity of any element, a bit over 14.3kJ/kgK at or near room temperature.  That's another way of saying it requires an enormous amount of heat energy input to raise the temperature of 2kg of H2 (the mass flow rate we previously agreed was necessary to achieve our thrust target) from 20K to 3,000K.

The radiation plume would've been a significant problem, but I feel like the overpressure effects from supersonic flight are a bit exaggerated.  Back when the Air Force was still studying this, researchers were uninjured by a 144psf overpressure produced by a supersonic F-4 flying 100ft overhead.

Roughly speaking, Project Pluto envisioned a F-4 mass vehicle (61,000lbs), albeit with significantly improved aerodynamics, moving at Mach 3 at low-level only for the penetration run into Soviet airspace, using its 513MWth / 35,000lbf engine.  However, this nuclear ramjet powered "cruise missile" would've flown at much greater altitudes while loitering and cruising into the target area.  Its onboard autopilot would direct the weapon to descend to treetop level only upon entering enemy airspace.  As far as "unlimited range" is concerned, that should be heavily qualified.  Range was estimated to be around 113,000 miles, so this thing could "only" fly around at Mach 3 for two days or so before the reactor core suffered too much thermal damage and/or the fuel was depleted to the point of no longer able to maintain Mach 3 flight speeds.  Perhaps the weapon could fly over longer distances at reduced speeds and temperatures, but the notion of it staying aloft for a month or more was mostly fantasy.

How or why this weapon would ever be more useful or more lethal than a conventional ICBM equipped with a dozen MIRV warheads is beyond my understanding.   ICBMs reach their targets in less than 20 minutes, regardless of where they're launched from, and travel at speeds far beyond Mach 3.  To this day, there are very few known-effective defenses against ICBMs.  Successful interceptor weapons typically cost more than the nuclear warheads / ICBMs they're being fired at.  There have been many successful interceptions of much smaller sea-skimming supersonic (Mach 2-3) anti-ship cruise missiles and target drones.

SpaceNut,

Another video of the same incident, posted on InstaGram:
nickvalencianews

Is your insinuation that a couple of white guys arrested another white guy because they're racist against white people?  The guy being arrested was whiter than the two officers arresting him.  That much is clear from the video you posted and the one I posted.  How did you equate that with his skin color being what led to his arrest?

Let's give this some time so we can figure out if "Mr Dindo Nuffin" threw bricks at the Police or tried to run them down with his car or interfered with an arrest, prior to being taken to the ground, since that's exactly what 95% of this stuff turns out to be.  This normally plays out as the Police telling someone to stop doing something or to leave, the person in question believes they're not obligated to follow verbal commands from the Police in public places (a city street is a public place), and then quickly finds out that reality and their beliefs about it don't match.  That's unfortunate, but happens quite often, especially to leftists with entitlement-superiority complexes.  The Police aren't perfect, a few of them turn out to be as unhinged as the people they're supposed to be chasing, and none of them are angels, but leftist media has repeatedly proven that they will tell any lie to support their agenda.

RobertDyck,

Since, offshoring didn't happen over 4 or even 10 years, reshoring won't be complete inside of 4 or even 10 years, either.  Nobody here in America is "attacking" Canada or Mexico.  Canada's worst enemy is its leadership, or lack thereof, not America, and certainly not President Trump.  He sees Canada as a failing state on the basis of demographics, and Mexico as a state overrun by criminals in addition to poor demographics, neighboring failing states at that, hence his stream of commentary on this topic.

Try taking the point for once, instead of the entire arrow.  If President Trump truly did not care about Canada and Canadians, then he would simply sit back and say / do nothing about it, and pretend everything was "fine".  It's not fine, though, is it.  Canada's demographics are horrific.  City busy bodies quit having kids, and nothing we say or do is going to fix that.  That's a "you problem".  No kids equals no future.  Your ideology and ways of doing things die with you.  Liberalism and globalism has become a self-correcting problem.  People who are so "airy-fairy" that they don't think a future generation is necessary are doomed to historical and cultural irrelevance.  Getting upset at me or President Trump for pointing that out, however crudely, doesn't solve the problem.

Prove me wrong.  Create some children of your own.  Hopefully you'll learn how to value someone beyond yourself in the process.  Get some first-hand experience with being "talked-at" instead of "talked-to", when your kids come home from school with ideas put in their heads by dictionary definition crazy people.  That's been so much "fun" for me to deal with.  The entire process of attempting to raise children with some basic direction and morals has been a very humbling endeavor- one which has made me appreciate my own parents ever-more as the years pass me by.  Whatever their mistakes, I could never claim that they did not do the best they knew how.  Invest in our collective futures instead of complaining about what went wrong with our past.  Pour some of that anxious energy into something more productive than getting overly-upset at whomever is currently in power.  That's what long term thinkers do.  They don't fixate on one generation of problems because they view the world in terms of multi-generational patterns and dynamics.  Today's problem is tomorrow's opportunity, but attitude and perspective truly do matter.

States That Have Lost the Most Manufacturing Jobs Since the Turn of the Century

RobertDyck,

We're going to start manufacturing more of what Americans need / want, right here in America.  Canada is welcome to do the same and I think Canadians should do that, for their own economic benefit.  You can continue complaining about President Trump until the cows come home, and no doubt will, but that is the only program America is running right now.  President Biden ran the same program, even though more of it was directed at manufacturing that America previously outsourced to Asian countries.  That means the past two Democrat and Republican administrations were broadly aligned on how we're handling trade policy going forward, if not the optics of how to present actions taken to the general public.  Whether the media sensationalized it, as they did under President Trump, or not, under President Biden, is irrelevant to actions taken.  Protectionism is either universally bad, or it's "do as I say, not as I do".  If the former were true, then other nations, such as Canada, wouldn't practice it.  If the latter is what they're aiming for, then that game is over, because we're not playing it with them anymore.

Globalism is dead.  It's not sustainable.  America is walking away from globalism because it's proven to be wasteful and ultimately self-destructive.  As Peter Zeihan frequently points out, the post-WWII Global Order established by the US was never an economics-based proposition for America, merely a bribe to allied nations to permit America to determine how to fight the Cold War against the Soviets without starting WWIII in the process.  That issue was successfully resolved about 35 years ago, without firing a shot.  The old Imperial Order would've already fought WWIII.  Right about now, we'd probably be using sticks and stones to start fighting WWIV.  Thankfully, none of that happened, due in no small part to American military leadership.  Whatever their character flaws and personal shortcomings, you're not speaking Russian or glowing in the dark, so our military strategy worked, despite all the real or imagined mistakes we made.

You think we should continue doing what we've been doing, which has been highly detrimental to American families and our national economy, for the purpose of making rich people richer and selling an endless variety of cheap products to people becoming ever-poorer from outsourcing.  The issue is that many people are no longer buying it, because they can't afford to, and they're no longer convinced that a bewildering array of meaningless choices are better than a few choices made about things that truly matter.  Bread and games hasn't solved any problems.  However brilliant or errant our new strategy is, we're attempting to turn a page by re-shoring manufacturing.  It's no longer "business as usual".  The American electorate has voted out status quo candidates during the past 3 election cycles, including President Trump.  There's an object lesson in there somewhere, as it relates to what the majority of Americans think about our present economics problems.  The men in this country, especially young men, aren't interested in purchasing more or cheaper trinkets, nor do they view bread and games with favor.  They certainly don't care about making rich men richer.  A growing number of them want to build something worth having.  They'd rather do business with people they know, and they're willing to forego endless variety if that means a better tomorrow.  Many of them think the current economic system leaves few realistic paths to family formation, which they do value but see as unrealistically achievable because they cannot give their prospective wives a comfortable middle class lifestyle on a single income.  A lot of them are turning back towards traditional religions, which offer something no amount of money / fame / business success ever could- faith in a purpose beyond pure selfishness and hedonism.  Radicals either don't understand this or refuse to place any value in it.

At the same time, the political left has had an endless series of identity crises stemming from the fact that they don't have, let alone share, any core values that they actually uphold.  They reactively wander between crusades against whatever they've been instructed to hate at the present time.  That has caused the working public to part company with liberalism and the Liberal / Globalist Economic Order.  Most people aren't built to exist in a "never ending now", because it's exhausting and empty.  The left's worldview has all the worst predilections of a dogmatic religion combined with the socially corrosive class warfare of socialism, with none of the other redeeming qualities of the traditional religions.  Their religion offers only everlasting bitterness and enmity.  They don't believe in any form of non-performative compassion or forgiveness of their neighbors, which alienated large swaths of the American electorate as a result.  Their behavior is endlessly punitive in nature for merely voicing disagreement with their beliefs.  You'd have to be naive beyond belief, scared beyond reason, or simply lack any introspection to think the mob won't eventually turn on whomever / whatever you represent to them.  That doesn't describe most people.  You can't remain naiver forever, the strongest fear eventually leads to numbness, and everyone will eventually catch an eyeful of their reflection in the mirror- most won't like what they see.

That "fact check" contains fictional terminology that carries no legal meaning with it:

In response to the Democrats' rejected (by Republicans) proposed change to the ACA law to allow illegal aliens to purchase US citizen subsidized health care via the ACA, Democrats refused to fund the US federal government by refusing to sign the appropriations bill authorizing spending.

"Undocumented immigrants" is leftist word salad nonsense for "illegal aliens".  Anyone who is a legal immigrant / alien is also a "documented immigrant / alien".  The legal distinction that actually matters is permission from our government to legally reside in the US.  Anyone who has permission to reside in America also has documentation of that legal decision.

US citizenship documentation for immigrants is obtained by attending an immigration status hearing before an immigration court of law.  The legal decisions made by our immigration courts of law is what determines legality.  The documentation received by a new citizen is evidence that a legal determination was made by those who have the legal authority to do so.  Receiving documentation means an immigrant's request for US citizenship was evaluated by a sitting US judge presiding over an immigration court of law, and determined to be of sufficient legal merit to grant citizenship.

The attempt to use suggestive language to conflate legality with documentation, in the minds of people who likely don't care enough to know anything about US immigration law to begin with, is yet another attempt by Democrats to usurp the rule of law.  There's nothing wrong with having a personal opinion about a law, but presenting an ideologically-held opinion as "fact" is a bridge too far.  Whenever a "fact check" contains ideological language mixed with legal terminology (such as "Affordable Care Act"), it's misleading at best, manipulative and fraudulent at worst.  It's crystal clear that Democrats don't respect our laws, except perhaps when the law can be wielded as a cudgel for political advantage.  When that fails, they resort to violence, which they support and encourage.

tahanson43206,

If I understand the request correctly, I'm going to install / publish the phpBB3 web app on our NewMars web server.

What about database requirements?

Do I need to install and configure a database schema on our MySQL Server as well?

Is this a "standard" phpBB3 setup, or have you customized the phpBB3 web app or the database schema in any way?

I'm talking about editing the php files or database schema tables and objects, not any photos you've added.

Edit:
This web app is purely for local storage of user-generated media files, such as the rocketry-related PowerPoint presentations / photos / videos created by GW Johnson, correct?

SpaceNut,

The overwhelming majority of energy consumption in all western homes, US or otherwise, is for direct heating and cooling applications.  Thermal energy accounts for almost 75% of all the energy consumed in the average home, possibly more now that large TVs / desktop computers / incandescent bulbs have largely been replaced by laptops or cell phones and LED bulbs.  That means a home's HVAC system is responsible for most of that 1.2-1.25kW figure.  Home solar systems that fit on the roof of the home cannot provide that energy directly, because they're insufficiently powerful.

We had 67 photovoltaic panels on the roof and 2 Tesla Power Walls next to the breakers of the last home we owned.  At no point in time did those devices directly provide the input electrical energy for our home's HVAC system, because they weren't capable of doing so.  I asked the licensed electrical engineer who sold us our home solar system, what would be required to directly power the 3 AC units associated with our HVAC system, and he told me that most of our property's back yard would also need photovoltaic panels covering it.  He said somewhere between double and triple the number of panels we actually had installed would be required to directly power our home's HVAC system, as well as another 2 to 4 Tesla Power Walls, in addition to the 2 Tesla Power Walls that were installed, to store more electrical power for use at night.  Such a large photovoltaic / battery bank system would also be 50% to 60% of our home's purchase price.  Texas does not allow ground-mount photovoltaic panels to be installed on residential property.

Our photovoltaics were, IIRC, 26.5% efficient, at BOL.  Converting photonic / thermal power to electrical power is not terribly efficient, but using rooftop and ground hot / cold sinks to power HVAC systems is more practical because so much power from the Sun is NOT lost up-front by using photovoltaics to convert the incoming photonic energy into electrical energy.  Until radically more efficient and less costly photovoltaics become available, the total quantity of thermalized photonic energy available from the Sun, per unit of collector surface area, is at least 3X greater, using less costly equipment.  In simpler terms, our home's rooftop provided sufficient surface area to host thermal power collection equipment capable of generating high temperatures for the "hot side" of the thermal power transfer loop.

90% (visible spectrum photons to thermal spectrum photons) vs 26.5% (photons to electron movement) is a much greater total percentage of input power to work with, per unit of collector surface area, especially since the energy consumption system it's primarily being fed into is a thermal power transfer system (an over-glorified refrigerant loop- a device that works on the principle of a hot and cold sink).  An HVAC system, a refrigerator, and cooking appliances all produce thermal output.

If most homes in America had 75% of their energy consumption provided by an onsite system that doesn't need to be connected to any grid, doesn't require a large amount of space in the yard, and doesn't require anything more complex and costly than some additional indoor plumbing to transfer thermal power from "rooftop water heat tech", that single change would deliver a major reduction in emissions at a cost that most people could actually afford to roll into their home's purchase price.  Although there certainly are more exotic materials and refrigerants such a system could use, we're mostly talking about steel and water.