New Mars Forums

Official discussion forum of The Mars Society and MarsNews.com

You are not logged in.

Announcement

Announcement: As a reader of NewMars forum, we have opportunities for you to assist with technical discussions in several initiatives underway. NewMars needs volunteers with appropriate education, skills, talent, motivation and generosity of spirit as a highly valued member. Write to newmarsmember * gmail.com to tell us about your ability's to help contribute to NewMars and become a registered member.

#126 2019-10-11 18:39:41

kbd512
Administrator
Registered: 2015-01-02
Posts: 4,615

Re: Asteroid Mining - profit from space

knightdepaix,

There's a treasure trove of super grade metal alloys, composites, and plastics in orbit around our planet, along with numerous solar arrays and rocket engines and fuels that can be repurposed or otherwise recycled.  It cost a fortune to put all that stuff up there over the decades, so there's no reason it shouldn't be recycled aboard ISS for future uses, rather than being permitted to uselessly burn up during reentry.  There's no reason that we shouldn't experiment with in-space construction techniques, as we'll need those materials later on to build true spaceships capable of routine interplanetary transits.  The tonnage of space-grade hardware that we've simply thrown away after a single use is truly staggering.  At the very least, we should have a mandate for pristine skies to observe any asteroids in Spaceship Earth's flight path.

Offline

#127 2019-10-12 03:30:41

Terraformer
Member
From: Logres
Registered: 2007-08-27
Posts: 3,362
Website

Re: Asteroid Mining - profit from space

At the very least, we should gather it all together to use as counterweights for tethers.


"I guarantee you that at some point, everything's going to go south on you, and you're going to say, 'This is it, this is how I end.' Now you can either accept that, or you can get to work." - Mark Watney

Offline

#128 2019-10-12 06:14:44

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 7,326

Re: Asteroid Mining - profit from space

For kbd512 re #126 ....

My understanding is that each item that remains in orbit is the responsibility of the launching nation, and that capture of an object needs to be cleared with the launching nation.  That may not be a major problem for a salvage company, but it IS a consideration ... a detail ... that needs to be taken into account.

The Soviet Union launched many tons of mass into a variety of orbits, and since it does not exist I presume the Russians inherit responsibility (and security concerns).

The US put plenty of spy satellites and other vehicles into orbit, and they too may be touchy about someone corralling one of those objects.

It would be useful to know if there is an established contact point for objects in orbit, and (perhaps?) an established protocol for negotiating salvage rights?

(th)

Offline

#129 2019-10-18 05:22:01

elderflower
Member
Registered: 2016-06-19
Posts: 1,262

Re: Asteroid Mining - profit from space

Capturing things doing the very high speeds that orbiting stuff has to do is a difficult issue. You might harpoon the big items and put something like dry ice clouds in the way of very small stuff, so slowing and deorbiting the paint particles, but what about the intermediate items?
The spiders have developed a highly effective method of arresting large (relatively) flying objects using sticky threads with built in braking for deceleration. Perhaps we could develop something along these lines to capture errand spanners, nuts and bolts, microsats and similar sized objects.
We have learned how to capture rifle rounds so maybe there could be some mileage in developing Kevlar nets with titanium plates, maybe something similar to bullet proof vest construction.

Offline

#130 2019-10-18 18:51:29

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 23,099

Re: Asteroid Mining - profit from space

Speed and mass makes for the danger of these pieces even from the small stuff pea size to large satelites dead in orbit. We have seen what happens with a piece of supercooled foam....these pieces of junk are a danger to all.

Offline

#131 2020-07-01 07:56:10

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 7,326

Re: Asteroid Mining - profit from space

For RobertDyck re #46

Your post showed up when I ran a search for "architecture"

http://newmars.com/forums/viewtopic.php … 464#p42464

While the post itself dates back to 2004, the skills and knowledge demonstrated by your work at that time are (I'm confident) still with you, and while details of specific procedures are no doubt rusty if you haven't used them for a while, they could be burnished and restored to full capability relatively quickly. 

I'm going out of my way to avoid suggesting a specific focus you might pursue.  Instead, I'm here inviting you to restart the innovative frame of mind you were in, and see if the (very small number of active) members of this forum might be able to give you positive feedback to keep the creative energies flowing.

(th)

Offline

#132 2020-07-01 17:05:10

RobertDyck
Moderator
From: Winnipeg, Canada
Registered: 2002-08-20
Posts: 6,743
Website

Re: Asteroid Mining - profit from space

tahanson43206, I'm not sure what to add. This thread is fairly complete. What more should I say?

Offline

#133 2020-07-01 17:12:40

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 23,099

Re: Asteroid Mining - profit from space

For this no ships no mining...as you need to be quite rich to foot that up front cost to get operations of mining off the ground and them whom would be paying for that commodity....

Offline

#134 2020-07-01 18:55:38

RobertDyck
Moderator
From: Winnipeg, Canada
Registered: 2002-08-20
Posts: 6,743
Website

Re: Asteroid Mining - profit from space

Sigh. Basic fundamentals. The basic premise is you don't use expendable rockets. And the commodities you harvest are precious metals: gold, silver, platinum and platinum group. Stockpile iron and nickel at the asteroid for some future in-space venture. Byproducts will include nickel, chrome, cobalt, molybdenum, and aluminum; these make an alloy called Inconel 617. Carbon monoxide will be brought to the asteroid to process the metals, that will be a source of carbon for the alloy. Make a heat shield of that alloy, simply with a 2 part mould. Make a back shell with another 2 part mould. Place bullion inside and arc weld the heat shield to back shell. A robot spacecraft will carry the aeroshell to Earth and drop on a desert. No parachute, no control rockets, no landing system or any sort of controls. Just 3 metric tonnes of metal falling out of the sky. Tell people to stay away. Pick up with a flatbed truck with a truck crane. You would want to send a helicopter with armed guards to ensure no one steels any of the precious metal. The bars will get dented or bent on impact; that's Ok. Gold is hard to separate from silver, so don't bother at the asteroid. This means you'll take the gold-silver bars to a refinery on Earth for final processing. It'll be melted anyway, so doesn't matter if it's bent.

And don't claim flooding the market will drop the price. This'll be just another mine. And gold is used for contracts for electronics, silver for solder, platinum/palladium/rhodium for catalysts. Every oil refinery needs this catalysts to convert heavy oil to something lighter like gasoline or diesel fuel. Every catalytic converter for cars uses those same metals. Hydrogen fuel cells need those same metals, so even an oil free economy cannot get away from them. There's a shortage of the catalytic metals right now.

Offline

#135 2020-07-01 18:57:05

RobertDyck
Moderator
From: Winnipeg, Canada
Registered: 2002-08-20
Posts: 6,743
Website

Re: Asteroid Mining - profit from space

The robot ship would drop the aeroshell then turn away, stay in space and head back to the asteroid for another load.

Offline

#136 2020-07-01 21:22:15

kbd512
Administrator
Registered: 2015-01-02
Posts: 4,615

Re: Asteroid Mining - profit from space

Robert,

Until 2.5kWh/kg batteries arrive, in order to make fuel cells, we need to flood the market with Platinum group metals to make them cheaper to manufacture and maintain than combustion engines.  We're roughly an order of magnitude away from achieving that goal for battery energy density, so we have the next best thing until those miracle batteries become reality.

Offline

#137 2020-07-02 16:28:37

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 23,099

Re: Asteroid Mining - profit from space

precious metals: gold, silver, platinum and platinum group metals ruthenium, rhodium, palladium, osmium, iridium,

https://en.wikipedia.org/wiki/Precious_metal https://en.wikipedia.org/wiki/Platinum_group
https://goldmastersusa.com/purchasing/gold_scrap.asp

http://nevada-outback-gems.com/copper-o … 20Ores.htm

Approximately 8 tons of raw ore must be mined to produce just one pure ounce of platinum. Roughly 90% of all platinum supplies come from South Africa and Russia.

Offline

#138 2021-06-29 05:07:07

Mars_B4_Moon
Member
Registered: 2006-03-23
Posts: 885

Re: Asteroid Mining - profit from space

We can already land on Comets and Asteroids like the Japanese and European missions did but can we live there maybe not yet.  mission did. Maybe there will be an economy out there Musk often talks about building some kind fo Galactic Stock Exchange and one day having a Bitcoin or a Dogecoin up there in space. Perhaps Mars is the much better option and putting miners on an Asteroid won't be happening any time soon....but then again.

Japan passes space resources law
https://spacenews.com/japan-passes-space-resources-law/
The House of Councilors, the upper house of the National Diet of Japan, passed the bill June 15. The lower house, the House of Representatives, approved the bill June 10. The bill has support from the two largest political parties, the ruling Liberal Democratic Party and the Constitutional Democratic Party.

The bill, formally known as the Law Concerning the Promotion of Business Activities Related to the Exploration and Development of Space Resources, grants Japanese companies permission to prospect for, extract and use various space resources. Companies that wish to do so must first obtain permission from the Japanese government.

Asteroid mining- Is it too good to be true?

https://onlyphysics.org/a-new-future-for-mining/

Last edited by Mars_B4_Moon (2021-06-29 05:12:51)

Offline

#139 2021-06-29 05:11:19

Mars_B4_Moon
Member
Registered: 2006-03-23
Posts: 885

Re: Asteroid Mining - profit from space

not today for now robots will do it before humans

maybe mining will become a real thing

Last edited by Mars_B4_Moon (2021-06-29 05:12:09)

Offline

#140 2021-06-29 21:37:41

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 23,099

Re: Asteroid Mining - profit from space

Mining will be more towards the benefit of those that need the raw materials. The choice to get them will be cost and fuel energy driven for where we might mine and what we might mine for. These goods will be used locally for the have nots as they need them due to distance to get them.

Offline

#141 2021-06-30 12:08:34

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 7,326

Re: Asteroid Mining - profit from space

For Mars_B4_Moon re #138

Thanks for the link to the article about asteroid mining.

Considering the authors are working with English as a second language (I'm assuming) the article stands up fairly well.

There ** is ** one error that anyone in the NewMars forum would instantly recognize ...

It doesn't detract from article, because it's in the wild-speculation section ...

https://onlyphysics.org/a-new-future-for-mining/

Authors- Teja Sreya and Avnish Chate

The minerals we mine from asteroids can help us build mega-structures in space like the Dyson sphere, (a sphere around the earth that gathers solar energy which acts as a source of energy depleting the energy crisis using renewable energy),

(th)

Offline

#142 2021-06-30 13:34:47

RobertDyck
Moderator
From: Winnipeg, Canada
Registered: 2002-08-20
Posts: 6,743
Website

Re: Asteroid Mining - profit from space

Ohhh... yea. A Dyson sphere is a theoretical sphere that surrounds the whole star. Science Fiction have depicted it as a hollow sphere, but Freeman Dyson actually left it undefined whether it's solid or just a collection of satellites that together collect all light emitted from the star. A hollow sphere has several problems: how do you create gravity on the inside surface so people can live there? How do you make such a thing stable? Wouldn't it wobble and crash into the star? Star Trek: TNG episode "Relics" S06E04 depicted such a hollow sphere. In a fictional universe that has "gravity plating", the gravity issue can be ignored. In real life, it can't. Larry Niven proposed an alternative to resolve these issues: Ringworld. Rather than a hollow sphere with radius equal to Earth's orbit, instead Ringworld is a ring around the star, also radius the same as Earth's orbit. Ringworld has a surface not as large as a Dyson sphere, but still several times the surface of Earth. And it can use centrifugal force for gravity. Stability around the star? Pshaw! Fiction doesn't worry about such things.

I've argued before against the idea of a solar power satellite. A satellite has bright uninterrupted sunlight 100% of the time. But the only way to transmit power to the ground is a microwave beam. The most efficient microwave power transfer beam delivers 30% of the power. If you put solar panels on the roof of your house, then 100% of the power will be available to your house. But there's only sunlight during the day, none at night. And sometimes during the day there's clouds. So you could get 30% sunlight. So 100% of 30%, or 30% of 100%... sounds like the final efficiency is the same. But putting solar panels on your roof requires a pickup truck to carry them from the store, and a ladder. Putting a satellite in space is a hell of a lot more expensive. Then there's repair... again pickup truck or SUV and a ladder vs orbital launch vehicle. Getting the point?

And that ignores the safety of a multi-megawatt microwave beam, enough to power a city, beaming down to the ground. If aim is off by a little, you microwave all the residents of that city. And what will that microwave beam do to climate? Since only 30% of the power is recovered, the other 70% goes to the atmosphere. That doesn't sound like a solution to global warming.

Offline

#143 2021-06-30 14:01:24

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 7,326

Re: Asteroid Mining - profit from space

For RobertDyck .... re #142

Thanks for picking up on the Dyson sphere error, and adding the Ringworld follow up ...

The figures you've posted are interesting (to me for sure) and they might be right, but they might be in need of adjustment ...

The efficiency of 30% ** might ** be the ratio of power delivered to the ground compared to the amount of power subtended by the solar panels or mirrors.

Could you clarify that?

One thing I am confident needs adjustment ... almost NONE of the power transmitted through the atmosphere is lost.

If you can find a reference for ** that **, I'd be amazed.

My corresponding estimate is 3% at most.

The beam from GEO has to travel through only 100 miles (162 km).

I asked Google for assistance to support my 3% guess, but since I'm on an ancient computer at the moment, I can't pursue the links.

Radio propagation - Wikipedia
en.wikipedia.org › wiki › Radio_propagation
Radio propagation is the behavior of radio waves as they travel, or are propagated, from one ... Several different types of propagation are used in practical radio transmission ... At different frequencies, radio waves travel through the atmosphere by ... The RF noise burst from the lightning makes the initial part of the open ...

Atmospheric Attenuation - an overview | ScienceDirect Topics
www.sciencedirect.com › topics › engineering › atmospheric-attenuation
The atmospheric transmission efficiency of the microwave beam depends on ... to eliminate periodic RF power fading caused by dispersion in optical fibers and ...

Which layer of atmosphere is important for transmission of radio waves?
Do radio waves pass through the atmosphere?
Does humidity affect RF transmission?
OSA | Studies on characterizing the transmission of RF signals over ...

www.osapublishing.org › abstract

Apr 27, 2009 · In this work, we aim at experimenting in actual deployment environment scenario the performance of RF signal transmission using a FSO link.
Radio-Frequency Communication

fas.org › spp › military › docops › afwa
In the upper levels of the ionosphere, ions are thinly spread and remain highly charged. ... The different layers in the atmosphere are caused by the different ... TESTWhen high-powered transmitters and efficient antennas are used, the surface ...

RF Safety FAQ | Federal Communications Commission

www.fcc.gov › ... › Radio Frequency Safety

This efficient absorption of microwave energy via water molecules results in rapid ... intensity of the RF environment at a given location in terms of units specific to ... It is common that not all antennas are used for the transmission of RF energy; ...

Electromagnetic radiation - Radio waves | Britannica

www.britannica.com › science › electromagnetic-radiation › Radio-waves

Transmission therefore involves not a single-frequency electromagnetic wave but rather a ... This width and the decrease in efficiency of generating. ... miles) above Earth's surface in which the atmosphere is partially ionized by ultraviolet light ...

Telecommunications media - Radio transmission | Britannica
www.britannica.com › topic › Radio-transmission

In atmospheric propagation the electromagnetic wave travels through the air ... ionosphere (as in shortwave radio; see below The radio-frequency spectrum: HF). ... An important measure of the efficiency with which a transmitting antenna ...
[PDF] The effect of temperature and humidity on the transmission of radio ...
digitalcommons.imsa.edu › cgi › viewcontent


other factors affect radio waves such as which frequency is most efficient and transmits the strongest radio ... lower temperature and lower relative humidity in the atmosphere. ... Figure 2.2 Radio Frequency energy losses due to scattering.

RF Path and Absorption Loss Estimation for Underwater Wireless ...
www.ncbi.nlm.nih.gov › pmc › articles › PMC4934316

Jun 16, 2016 · The intricacies presented by the underwater environment are far more ... To design an efficient and robust UWSN, the characteristics of underwater ... transmission distance and nature of communication in underwater.
[PDF] Radio frequency propagation differences through various ...

digital.library.unt.edu › ark: › metadc5801 › high_res_d › thesis
selection, tuning and maintenance, increasing the efficiency of the network and ... Null: There is no difference in signal transmission through Styrofoam, Lexan ... To propagate radio waves through Earth's atmosphere, the energy must be.
Related searches

I see a pdf in that list ... I'll try to pull it down ...Nope ... the site is protected.

The ** truth ** lies somewhere between 70% and 3%

(th)

Offline

#144 2021-06-30 14:20:29

RobertDyck
Moderator
From: Winnipeg, Canada
Registered: 2002-08-20
Posts: 6,743
Website

Re: Asteroid Mining - profit from space

Last I read, microwave beamed power has only been successful across a short distance, a few miles, less than 10. And only 30% collected at the other end. Transmitted through the atmosphere requires at least 100 km (62.1 miles). Above that is tenuous atmosphere, so yea, a lot. And getting through the ionosphere will be non-trivial. It's been a number of years, so let's see what I can find.

Wikipedia: Wireless power transfer

Power transmission via radio waves can be made more directional, allowing longer-distance power beaming, with shorter wavelengths of electromagnetic radiation, typically in the microwave range. A rectenna may be used to convert the microwave energy back into electricity. Rectenna conversion efficiencies exceeding 95% have been realized.[citation needed] Power beaming using microwaves has been proposed for the transmission of energy from orbiting solar power satellites to Earth and the beaming of power to spacecraft leaving orbit has been considered.

Power beaming by microwaves has the difficulty that, for most space applications, the required aperture sizes are very large due to diffraction limiting antenna directionality. For example, the 1978 NASA study of solar power satellites required a 1-kilometre-diameter (0.62 mi) transmitting antenna and a 10-kilometre-diameter (6.2 mi) receiving rectenna for a microwave beam at 2.45 GHz. These sizes can be somewhat decreased by using shorter wavelengths, although short wavelengths may have difficulties with atmospheric absorption and beam blockage by rain or water droplets. Because of the "thinned-array curse", it is not possible to make a narrower beam by combining the beams of several smaller satellites.

For earthbound applications, a large-area 10 km diameter receiving array allows large total power levels to be used while operating at the low power density suggested for human electromagnetic exposure safety. A human safe power density of 1 mW/cm2 distributed across a 10 km diameter area corresponds to 750 megawatts total power level. This is the power level found in many modern electric power plants. For comparison, a solar PV farm of similar size might easily exceed 10,000 megawatts (rounded) at best conditions during daytime.

Following World War II, which saw the development of high-power microwave emitters known as cavity magnetrons, the idea of using microwaves to transfer power was researched. By 1964, a miniature helicopter propelled by microwave power had been demonstrated.

Japanese researcher Hidetsugu Yagi also investigated wireless energy transmission using a directional array antenna that he designed. In February 1926, Yagi and his colleague Shintaro Uda published their first paper on the tuned high-gain directional array now known as the Yagi antenna. While it did not prove to be particularly useful for power transmission, this beam antenna has been widely adopted throughout the broadcasting and wireless telecommunications industries due to its excellent performance characteristics.

Wireless high power transmission using microwaves is well proven. Experiments in the tens of kilowatts have been performed at Goldstone in California in 1975 and more recently (1997) at Grand Bassin on Reunion Island. These methods achieve distances on the order of a kilometer.

Under experimental conditions, microwave conversion efficiency was measured to be around 54% across one meter.

A change to 24 GHz has been suggested as microwave emitters similar to LEDs have been made with very high quantum efficiencies using negative resistance, i.e., Gunn or IMPATT diodes, and this would be viable for short range links.

In 2013, inventor Hatem Zeine demonstrated how wireless power transmission using phased array antennas can deliver electrical power up to 30 feet. It uses the same radio frequencies as WiFi.

In 2015, researchers at the University of Washington introduced power over Wi-Fi, which trickle-charges batteries and powered battery-free cameras and temperature sensors using transmissions from Wi-Fi routers. Wi-Fi signals were shown to power battery-free temperature and camera sensors at ranges of up to 20 feet. It was also shown that Wi-Fi can be used to wirelessly trickle-charge nickel–metal hydride and lithium-ion coin-cell batteries at distances of up to 28 feet.

In 2017, the Federal Communication Commission (FCC) certified the first mid-field radio frequency (RF) transmitter of wireless power.

So real-world experiment resulted in 54% across one metre.

Last edited by RobertDyck (2021-06-30 14:30:01)

Offline

#145 2021-06-30 15:03:54

louis
Member
From: UK
Registered: 2008-03-24
Posts: 6,865

Re: Asteroid Mining - profit from space

A lot of financial analyses of asteroid mining are based on Earth-to-asteroid rocket flight costs. We know these will fall dramatically with development of the Starship. But is Earth 2 Asteroid the right way to look at this?

I can imagine a system where perhaps you take chunks of an asteroid - using robot miners of course - and load them (robotically) into your Starship that then returns to Earth orbit. The chunks are put into purpose-built units with parachutes and fired towards Earth. Perhaps there will be some sophisticated "Chunk-catcher" at sea or on the ground.

The parachute units are recovered and can be returned to the orbital Starship(s) periodically.

The advantages of this system are that:

(a) propellant usage would be much. much lower that otherwise would be the case and Starship would last much longer without having to ascend from and descend to Earth multiple times

(b) speed is not of the essence (with no humans involved)...even if it takes your robot Starship two years to do the round trip, it doesn't matter if you have maybe ten Starships working off the same asteroid - you'll have a steady supply of minerals returning to Earth at about 2-3 month intervals

(c) no humans are used in the production process.

Would still require a high value mineral, high purity ore and also development of robot mining technology - but the latter is more a matter of adapting the robot mining technology that already exists on Earth.


Mars_B4_Moon wrote:

We can already land on Comets and Asteroids like the Japanese and European missions did but can we live there maybe not yet.  mission did. Maybe there will be an economy out there Musk often talks about building some kind fo Galactic Stock Exchange and one day having a Bitcoin or a Dogecoin up there in space. Perhaps Mars is the much better option and putting miners on an Asteroid won't be happening any time soon....but then again.

Japan passes space resources law
https://spacenews.com/japan-passes-space-resources-law/
The House of Councilors, the upper house of the National Diet of Japan, passed the bill June 15. The lower house, the House of Representatives, approved the bill June 10. The bill has support from the two largest political parties, the ruling Liberal Democratic Party and the Constitutional Democratic Party.

The bill, formally known as the Law Concerning the Promotion of Business Activities Related to the Exploration and Development of Space Resources, grants Japanese companies permission to prospect for, extract and use various space resources. Companies that wish to do so must first obtain permission from the Japanese government.

Asteroid mining- Is it too good to be true?

https://onlyphysics.org/a-new-future-for-mining/

Last edited by louis (2021-06-30 15:08:09)


Let's Go to Mars...Google on: Fast Track to Mars blogspot.com

Offline

#146 2021-06-30 16:00:28

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 7,326

Re: Asteroid Mining - profit from space

For RobertDyck re #144

Thanks for engaging on this subtopic .... Because this is Asteroid Mining, and solar power is not directly related, I'll look for a more appropriate topic to reply.

That said, thanks for the 54% figure ...  I am looking forward to learning where that 46% of loss went.

(th)

Offline

#147 2021-07-10 12:39:48

Mars_B4_Moon
Member
Registered: 2006-03-23
Posts: 885

Re: Asteroid Mining - profit from space

The US Is Trying to Hijack Space Mining??
https://singularityhub.com/2020/10/12/t … sequences/
They want it to be a Global Project?

It could also kick up dangerous amounts of lunar dust that can cause serious damage to space vehicles, increase the amount of space debris, or in a worst-case scenario, create meteorites that could threaten satellites or even impact Earth.

They want a new Space Moon Law so it will start global?

Offline

#148 2021-07-10 16:49:34

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 23,099

Re: Asteroid Mining - profit from space

At just 1 meter that falls in the air gap formulas and transmission of a coil to coil system….

Offline

#149 2021-07-11 10:50:39

GW Johnson
Member
From: McGregor, Texas USA
Registered: 2011-12-04
Posts: 4,576
Website

Re: Asteroid Mining - profit from space

We will eventually see some sort of asteroid mining business attempted.  I'm unsure how soon.  I'm also unsure what that business will actually be looking for in those objects.

I've seen a lot of talk about mining volatiles to make propellants and other useful commodities in space.  That's fine,  but I predict (based on science reports) that very few of the small bodies contain significant volatiles.  Even the so-called "dirty snowball" comets so far have turned out to be much drier than expected:  more like a rubble pile with a bit of frost in it.

The space settlement enthusiasts talk about using these things for construction materials.  Yeah,  right!  Just how do you make a real engineering material out of charcoal-like crud mixed with rocks and rock dust?  No one has ever said in public precisely how to go about doing that,  and melting the rocks for "basalt fiber" is going to be prohibitively-expensive energetically.  You need a really big fire (heat source) to melt even a small rock. 

And that's the C-types (carbonaceous).  The S-types (stony) seem to lack the charcoal bits,  so you are down to nothing but rocks and rock dust.  Only the M-types (metallic) look useful as material sources (for iron) to me,  and they seem to be quite rare. 

The volatiles would appear to me to be only inside the really big ones like Ceres and Vesta.  And nobody yet knows whether those white outcrops are ice or salts.  Odds are,  exposed to space like that yet persistent,  those white spots are salts.  Not ice.

Further,  how do you latch onto a loose rubble pile in zero-gee?  You cannot drive a stake into it and expect it to hold a significant force.  Stakes work by friction,  where the friction force is a fraction of the normal force to the surface of the stake.  In zero-gee,  there is no normal force to the stake,  because all the bits are weightless.  So there is no friction to hold the stake in place when you exert a force upon it. 

Sorry,  that's just the physics.

You can't just lasso the thing with a loop of rope or a mesh-type net.  Everywhere a rope exerts a force upon the surface,  the rubble particles just move apart to let the rope pass right through the object,  because the gravity force that would otherwise bind them together is essentially zero.  Over time the cloud of particles reassembles into an "asteroid",  because the gravity is not exactly zero,  but for all other practical purposes,  it is essentially zero.

Again,  sorry,  that's just the physics.  And it applies to deflection schemes for asteroid defense,  too!

You'll have to fully enclose the thing inside some container to work with it.  If it's bigger than a very few meters,  that will be very,  very hard to do with anything you can afford to send there,  even if you solar-sail your way there.  And if it's only meters in size,  the odds are it will be dry as a bone,  no volatiles to harvest at all.  Just rocks,  rock dust,  and some charcoal-like bits if it's a C-type.

So I ask again:  just what the hell are you going to do with rocks,  rock dust,  and charcoal bits,  that would make you a profit?  No one has ever given me an answer to that question that wasn't dreamy BS.

I'd really like to know.

GW

Last edited by GW Johnson (2021-07-11 10:57:57)


GW Johnson
McGregor,  Texas

"There is nothing as expensive as a dead crew,  especially one dead from a bad management decision"

Offline

Board footer

Powered by FluxBB