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#651 2021-02-01 08:10:07

tahanson43206
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Registered: 2018-04-27
Posts: 17,907

Re: Large scale colonization ship

For RobertDyck re topic ...

Thanks for your two replies, restating your preferences about how the Large Ship will operate, and how it will be funded.

I think I've been VERY supportive, and remain so.  I have tried to offer objections that anyone willing to consider passage on your vessel would have.

I have repeatedly pointed out that spending on propellant for a safe "docking" at Mars is well worth planning in your budget, because the alternative is to spend enormous sums to create a structure capable of withstanding the stresses of aerocapture at Mars, let alone Earth, and you would be placing your passengers and crew at greater risk than they are already taking by embarking upon a space ship in the first place.

In a situation like that, your prospective passengers are going to be able to decide for themselves whether spending 30% more to arrive safely, versus 30% less to take a 50/50 chance of plowing a furrow in Mars is the better investment.

People willing to spend $55 million in today's economy are likely to want to have a reasonable assurance of safely arriving at the destination.  They are doing so AFTER seeing others take the risks of first flight and landing.   Are your passengers going to be any different, even if they pay less?

We may have different timelines imagining the Large Ship coming into existence.  I'm seeing it in 10 years, serving the market Elon Musk is creating, and I think you may be seeing it out a bit further in time.

Why not plan for a fleet instead of just one ship?  Allow your captains to specify the risks they are willing to take.  If you find one willing to earn a bonus for flying through the atmosphere on the first flight, go for it.

Aside from the matter of how to match orbits with Mars, this topic is slowly accumulating a wealth of detail for planning the Large Ship.  What is needed is said to be available in the Mars Society infrastructure ... a permanent searchable repository of specifications for a specific design or practice.

Until that becomes available, we are depending upon human memory of posts in the archive.

(th)

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#652 2021-02-01 15:53:04

RobertDyck
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From: Winnipeg, Canada
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Re: Large scale colonization ship

We have very different views of aerocapture. It's a technology. NASA has become a bureaucracy, very risk averse. That's extremely harmful. The NACA was created in March 1915 for the purpose of advancing aircraft technology. The problem was commercial companies do not like risk; they want guaranteed return on investment. With any technology development, you don't have any guarantees. So the NACA was created as a government agency, funded by the US federal government and with the country's best academics in the field. Mandate of the NACA was to develop high-risk/high-payoff technologies. It work; aircraft advanced quickly. They developed new technologies that commercial companies did not want to invest in. But after they got each technology to work, commercial companies were certainly willing to exploit them for profit. After the Soviet Union launched Sputnik, the NACA became NASA. The original mandate of NACA is still part of NASA, they still develop new technologies for aircraft. But NASA is supposed to do the same thing for space. From 1958 through the 1960s and early 1970s, NASA achieved great things! But since Apollo was cancelled, NASA has become afraid. This is harmful, and NASA is not able to do what they exist for as long as they do this.

Aerocapture is a very important technology. Like anything else, it has to be developed and tested. Yes, that means using it for unmanned orbiters. They should be using it for absolutely every orbiter sent to Mars. Keep doing it until it's a mature technology. Then we can use it for human missions. No, it's not a "50/50 chance of plowing a furrow in Mars". The reason Mars Climate Orbiter failed was a stupid mistake: they made a unit error. We know the problem, NASA administrator Dan Goldin ordered everything be done in metric.

I live in Winnipeg, in 1983 a commercial jet airliner was supposed to fly from Montreal to Edmonton, over-flying Winnipeg. But the technician who loaded fuel made a conversion error, he put in too little fuel. The pilot was supposed to double-check the fuel load, but he made the same mistake. It ran out of fuel, had to glide to an airport. A 767 full of passengers. It didn't have enough energy to make it to the Winnipeg airport, so redirected to a decommissioned air force training base in the small town of Gimli. It took a remarkable act of piloting to land safely, but he did. The runway had been converted to a drag strip for race cars, there was a metal barricade down the centre of the runway. Aircraft nose landing gear didn't lock, it scraped the pavement and crushed the barricade. Friction with the aircraft skin skidding on the pavement started a fire in insulation, but race car drivers had fire extinguishers so quickly put out the fire. The incident was called the "Gimli Glider". One would think this is enough of a lesson about mixing measurement systems, but no, JPL had to do it themselves.

Yes, aerocapture has to be thoroughly tested with unmanned orbiters before it's done with crew. But that can be done. And again, no its not a "50/50 chance of plowing a furrow in Mars".

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#653 2021-02-01 18:12:31

RobertDyck
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From: Winnipeg, Canada
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Re: Large scale colonization ship

One major point in the "Corporate Government" thread was how to make money from Mars. Transporting anything back to Earth costs too much, so what? My solution is transport of settlers. So the Large Ship is the primary source of revenue for the Mars venture. Passengers will pay their entire life savings just for a ticket to Mars: liquidate their life insurance, liquidate their pension, sell their house and car, sell everything they can't carry with them. This gives them a ticket for their family (husband, wife, children), clothes they wear, and some luggage. More wealthy individuals with arrive with equipment to build a homestead, but many workers will not. That's Ok. The "Corporation" is hiring!

Once set up, the ship will be maintained from Mars. All parts for repair and maintenance will be built on Mars. All food for transit in both directions will come from greenhouses on Mars. Propellant for return from Mars orbit to Earth will come from either Mars, or a martian moon. Propellant for transit from Earth to Mars will come from a depot in Earth orbit. That will be filled from either an an asteroid mine, or one of the martian moons. So cost of operating the ship comes from the space economy, but passengers pay in Earth currency. The only expenses are a shuttle to carry passengers from Earth surface to the ship in LEO, advertising, and passenger orientation & quarantine. I thought of this before Elon Musk announced Starship; now I'm thinking that shuttle will be Starship. To ferry passengers and cargo from Mars orbit to the surface, another Starship or two permanently parked on Mars.

One example that I intend to put in the fiction book. A tradesman living in Toronto wants a better life on Mars. He's single, purchased a small townhouse in Toronto. I looked at real estate listings and found one advertised. Actually, an article talked about this real estate prices across Canada. One bedroom, 1 bath, 670 square feet. Real estate article claims a view of Lake Ontario, but the picture from the article shows it has a view of a concrete wall, with nothing but a sidewalk between the wall and row of townhouses. Down the sidewalk you can see downtown buildings and top of the CN Tower over the top of the buildings. The lake is not at all visible. In the UK these are called "row houses"; not terraced, not detached. So in this example, the worker paid 5% down payment when he bought the home, then made regular mortgage payments for 10 years. Owned a used car. Owned some sporting equipment, but nothing spectacular. To move to Mars, he sells everything. This gets him a bunk in an economy cabin on the Large Ship. That's a bunk in a small cabin with 5 strangers. Storage space under his mattress equivalent to a bunk on an American aircraft carrier, plus one row of drawers under the lower bunk. The cabin has no storage closet, no locker, this is all he gets. This example worker brings his tools for his trade, and one large duffle bag of stuff stored in the cargo hold. If he wants to bring more cargo, it costs extra; but in this example he can't afford that. While on the ship he gets free food at any of the buffet dining rooms, but booze at the bar or a meal in the fine dining room costs. The room includes a ship's housekeeping steward (maid) cleaning the room doing do doing his laundry once per week. Wifi on the ship is free, he can use a tablet to read technical manuals, Kindle novels, Netflix, YouTube, Facebook, etc. He can surf the web, although websites might have a delay. The ship will have a web server that caches common websites used by passengers, and if you request a website that isn't there, the server will download that site from Earth. Download could take up to 23 minutes, depending on distance from Earth.

All passengers will arrive on Mars at a Company owned city. Arrivals will have electronic advertising everywhere: come work for the Company! Free apartment, free utilities, free healthcare, free transportation to work, there's even a free company cafeteria! Of course the cafeteria is for Company employees only; if you want to meet a friend, it'll have to be at a restaurant off Company premises. Transportation will probably be a corridor from the dormitory, or company bus to a mine site, etc. Can you save enough money to buy all the stuff you need to build a homestead in the outback? All equipment available from the Company store.

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#654 2021-02-01 20:35:49

SpaceNut
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Re: Large scale colonization ship

Something for a page ago on food crops to grow both on this ship but on Mars as well in crops. 26 Plants You Should Always Grow Side-By-SideBB139n8q.img?h=399&w=799&m=6&q=60&o=f&l=f

These combinations of plants do way better, together:

Roses and Garlic
Gardeners have been planting garlic with roses for eons since the bulbs can help to repel rose pests. Garlic chives are probably just as repellent, and their small purple or white flowers in late spring look great with rose flowers and foliage.

Marigolds and Melons
Certain marigold varieties control nematodes in the roots of melon without using chemical treatments.

Tomatoes and Cabbage
Tomatoes repel diamondback moth larvae, which can chew large holes in cabbage leaves.

Cucumbers and Nasturtiums
The nasturtium's vining stems make them a great companion rambling among your growing cucumbers and squash plants, suggests Sally Jean Cunningham, master gardener and author of Great Garden Companions>>>P. Nasturtiums reputedly repel cucumber beetles, but they can also serve as a habitat for predatory insects like spiders and ground beetles.

Peppers and Pigweed
Leafminers preferred both pigweed (also called amaranthus) and ragweed to pepper plants in a study at the Coastal Plains Experiment Station in Tifton, Georgia. Just be careful to remove the flowers before the weeds set seed.

Cabbage and Dill
"Dill is a great companion for cabbage family plants, such as broccoli and brussels sprouts," Cunningham says. The cabbages support the floppy dill, while the dill attracts the helpful wasps that control cabbage worms and other pests.

Corn and Beans
The beans attract beneficial insects that prey on corn pests such as leafhoppers, fall armyworms, and leaf beetles. The vines can also climb up the corn stalks.

Lettuce and Tall Flowers
Nicotiana (flowering tobacco) and cleome (spider flower) give lettuce the light shade it grows best in.

Radishes and Spinach
Planting radishes among your spinach will draw leafminers away from the healthy greens>>>P. The damage the leafminers do to radish leaves doesn't prevent the radishes from growing nicely underground.

Potatoes and Sweet Alyssum
The sweet alyssum has tiny flowers that attract delicate beneficial insects>>>P, such as predatory wasps. Plant sweet alyssum alongside bushy crops like potatoes>>>P, or let it spread to form a living ground cover under arching plants like broccoli. Bonus: The alyssum's sweet fragrance will scent your garden all summe longr.

Cauliflower and Dwarf Zinnias
The nectar from the dwarf zinnias lures ladybugs and other predators that help protect cauliflower>>>P.

Collards and Catnip
Studies have found that planting catnip alongside collards reduces flea-beetle damage on the collards. The fragrant plant may also help repel mosquitoes>>>P.

Strawberries and Love-In-A-Mist
Tall, blue-flowered love-in-a-mist (Nigella damascena)"looks wonderful planted in the center of a wide row of strawberries," Cunningham says.

Flowering plants do more than look good....

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#655 2021-02-01 20:49:17

RobertDyck
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From: Winnipeg, Canada
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Re: Large scale colonization ship

This may sound hospitality related, but it relates to size of equipment needed on the ship, and supplies. How much booze do we need?
Shipfaced: Alcohol on Cruise Consumption

Per Cruise Passenger / Per Day

  • 0.3 glasses of champagne

  • 0.7 beers

  • 1.2 glasses of wine

  • 2.4 mixed drinks

For 1,000 passengers each week that requires:

  • 372.6 litres of champagne @ 6 ounce glass

  • 1,738.9 litres of beer @ 12 US ounces

  • 1,242 litres of wine @ 5 ounces

  • 745.25 litres of hard liquor @ 1.5 ounces per drink

With beer made on-site from malt, and beer takes 4 weeks, that requires 6,955.6 litres of fermentation vats. That's 1,530 UK gallons! Shall we round to 1,500 gallons? To make 5 UK gallons requires 1.7kg malt. So this requires 510kg of malt per week. For a 26 week trip (182 days) the ship will have to carry 13,260kg of malt. Sugar can be made by using an enzyme to break down starch from the chloroplast oxygen generators. Water is of course recycled.

This website says wine takes 3 months "Wine has matured more, and gained increasing flavors and distinctions", or 6 months "The typical time for aging wine, both red and white. Here your wine has a great taste, and doesn't really need any longer maturing." For 10+ months "Matures the flavor of your wine even further. Can create more bitter, unique flavors. The longer you age, the more unique." I've made wine from grapes, it can be drunk after 3 months. So do we get cheap and just ferment for 3 months? Better yet, ferment ahead of time, let the wine age for at last 6 months if not more. I could go on about schedule.

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#656 2021-02-01 21:03:40

SpaceNut
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Re: Large scale colonization ship

Depends on how functioning you want the crew and passengers as stupid does as stupid will....

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#657 2021-02-01 22:11:24

RobertDyck
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Re: Large scale colonization ship

Spacenut, there are no bugs in space. We have to ensure everything we send up is clean. This is another reason why passengers will not be allowed in the greenhouse. Passengers will be quarantined before launch, but still. Observation decks will have potted plants. We could make them different than each other, just for variety. And the plants could be useful. Orange trees for vitamin C, juniper bushes for gin. Your list doesn't require planting anything with them, allowing passengers to interact should be Ok. Hmm, gin can be flavoured with rose petals and dried orange peel. Spices also on the observation deck? Anything in the open where passengers can access has the danger that they would help themselves, possible when not yet ripe. We would want food crops in greenhouses off limits to passengers. However, they probably wouldn't interfere with spices. Possibly coriander aka cilantro? It's a small plant. And cardamom? Larger, 5 to 10 feet tall, but grows in shade so could be grown under an orange tree. These are spices that can be used for gin. Could also be used for cooking. I'm tempted to suggest apples, but citrus has more vitamin C.

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#658 2021-02-01 22:13:13

RobertDyck
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From: Winnipeg, Canada
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Re: Large scale colonization ship

SpaceNut wrote:

Depends on how functioning you want the crew and passengers as stupid does as stupid will....

Crew will have to remain sober, but what will passengers do for 6 months? They could give lectures to other passengers about their area of expertise. But how much of that can you do?

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#659 2021-02-14 20:33:42

tahanson43206
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Posts: 17,907

Re: Large scale colonization ship

The Space Show for February 7th should be of interest to several NewMars forum members.

https://www.thespaceshow.com/show/07-fe … as-spilker

Guest:  Dr. Tom Spilker;  We discussed funding, engineering, design and architecture for The Gateway Foundation with the Orbital Construction Company on orbit space habitat and space hotel.


The discussion includes an explanation for why 3 RPM is not under consideration for the space habitat.

It appears that the design is aiming for a rotation rate of 1.5 RPM.

The station is planned to offer high quality food service.

An early experimental version of the design is planned for construction on Earth.

Edit#1: The Gateway Foundation was established long before NASA chose the word "gateway" for one of its projects, and has nothing to do with it.


(th)

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#660 2021-02-15 01:50:47

RobertDyck
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Re: Large scale colonization ship

Interesting. The guest said his design will have 60 metre diameter. I said mine will have 37.6992 metre radius, which is 75.3984 metre diameter. Mine is just a touch larger.

He said his station will have centroids 91.3 metres, Lunar gravity @ 1.26 RPM. At 3 RPM people would take several days, possibly a week to get used to it.
You realize Mars gravity @ 1.5 RPM would require radius of 150.7967 metres. That's diameter of 301.5934 metres plus thickness of the floor, and radiators hanging on the outside of ring.

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#661 2021-02-15 03:38:33

Calliban
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From: Northern England, UK
Registered: 2019-08-18
Posts: 3,542

Re: Large scale colonization ship

One option for aerocapture that might be worth exploring is a high altitude drag chute.  This would be a huge but thin fibreglass parachute that the colonisation ship pulls behind it.  The ship would graze the Martian atmosphere at a height of about 100km.  The parachute would exert enough drag on the ship to put it into an elliptical orbit around Mars.  With successive passes through the Martian ionosphere the apogee would be reduced to the point where a small burn at apogee would raise the perigee to 400km and circularise the orbit.  The chute can then be ejected, or better still, reeled in for reuse.

Basalt fibre would be a good choice.  The fibres would be vacuum coated with aluminium to prevent fibres from damaging each other as they rub over each other in a vacuum.  The same drag chute could be used to achieve at least part of the velocity change needed for Earth orbit insertion.  After a certain number of uses, the chute would need to be abandoned, as the aluminium coating on the fibres would eventually get degraded by oxygen ions in the upper atmosphere of Earth and Mars.

Last edited by Calliban (2021-02-15 03:51:26)


"Plan and prepare for every possibility, and you will never act. It is nobler to have courage as we stumble into half the things we fear than to analyse every possible obstacle and begin nothing. Great things are achieved by embracing great dangers."

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#662 2021-02-15 07:01:34

tahanson43206
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Re: Large scale colonization ship

For RobertDyck re #660

Thanks for taking a ? look ? at that interview!  I thought there might be elements of the business plan the group is pursuing that might be of interest.

I was happy to see serious mention of fine dining, which is a feature of the Large Ship vision that I like (along with several other features).

One aspect of your response in #660 might be worth developing a bit .... the speaker expressed the opinion that the average human would need some time to acclimate to the 3 RPM rotation you are proposing.  To my ear, that sounded like a perfect business opportunity for an enterprising organization.

A crew planning a trip on one of your Large Ships (which I have no doubt will become a fleet in time) would be able to prepare by booking a stay at a ? hotel ? in LEO, where the RPM would start out at 1 (which is universally regarded as the gold standard) and then gradually increase to 3, just in time to transfer to your scheduled liner's departure.

Of course at 1 RPM the gravity would be less than the target of Mars normal.

You ** could ** put up a facility for G acclimatization long before the Large Ship is back from its first unmanned test flight.

An aspect of the business plan I found interesting is construction of a test facility on Earth, made out of steel.  As you would have noted, the plan for the on-orbit version is calling for Aluminum.  You could build a test facility on Earth, with a banked track so that you could give your prospective customers a sense of what 3 RPM might feel like.  You could even offer fine dining in the test facility.

(th)

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#663 2021-02-15 11:53:27

RobertDyck
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Re: Large scale colonization ship

Yes, a number of things were quite interesting. They compared specifically to 3 RPM. Not 2, not 4, but 3. And they mentioned fine dining, and a bar, and a brig. My ship is 30 and a bit metres radius, while his "test" facility is 60 metres diameter. He got initial funding through crowd funding. I was considering crowd funding. Sounds as though he's reading this forum.

That said, his idea of a large space station built from separate modules with multiple DreamChaser shuttles permanently docked is different and predates mine.

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#664 2021-02-15 14:50:40

SpaceNut
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Re: Large scale colonization ship

Drag chute would need a means to lower into atmosphere possibly long sky crane cable wrinch, have an inflateble ring to force it open, ring guard venting for pressure build up control just to suggest possibility.

About all that remains is how to get it built timeline, at what cost with projected costs to potential customers.
Taxi to get crew plus passengers with cargo to it once built.
Slating of mission time frame for mars mission.

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#665 2021-02-15 16:54:13

RobertDyck
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Re: Large scale colonization ship

Well, something this big you can't just spin up and down. It takes a lot to get it spinning. Momentum. To produce Mars gravity with 1.5 RPM or less would require splitting the ring into two or more segments. That splits up the ship with an elevator to/from the zero-G hub to move between segments. That keeps passengers effectively separated from each other, and ship facilities separated. A ship with separate segments becomes impractical to aerocapture. A solid ring with thermal fabric to act as a heat shield could withstand the forces, but not separate segments. Notice Voyager Space Station by the Gateway Foundation is separate modules docked together, and cables holding it together like spokes of a bicycle wheel. That wouldn't withstand aerocapture.
banner-vonbraun.jpg

The Space Show interview did talk about "Gravity Ring" as a separate thing built before Voyager Space Station.

He also said Gravity Ring would have a despun section for docking, with 2 docking ports. It would only be despun during docking. This means a bearing, and changing whether it's rotating. That adds additional problems. He doesn't think a ship can dock while spinning. Here's a GIF showing Orion III spaceplane docking with Station V in the movie "2001: A Space Odyssey".
0959d02265c08fc6dd8ec675adfc6551.gif

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#666 2021-02-20 11:39:49

tahanson43206
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Re: Large scale colonization ship

Here are a couple of items that showed up today ...

Airbus to build 'first interplanetary cargo ship'

Europe pushes ahead with 'dune buggy' Mars rover

If someone would care to find out more you are certainly welcome.  It'll be a while before I can get back to it.

(th)

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#667 2021-02-22 06:51:59

tahanson43206
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Posts: 17,907

Re: Large scale colonization ship

For RobertDyck re topic ...

It came up recently in another topic that the Large Ship is currently unable to protect a crew from radiation.

A possibility came to mind recently, as I thought about the Large Ship .... If you extend the central shaft an equal distance from the center, you would have a shape that remains symmetrical, but has a potential application not possible with the original hammerhead design.

I wonder if a bar magnet concept could be implemented to run through the central shaft, to create a field around the Large Ship, perhaps extending far enough from the central shaft to provide protection for the passengers in the habitat ring.

We may not have anyone in the current membership who can perform the physics calculations needed to confirm or falsify this concept, but we certainly can launch a Help Wanted request for assistance by a qualified person.

(th)

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#668 2021-02-22 12:02:13

RobertDyck
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Re: Large scale colonization ship

From 2002, University of Washington, paper as PDF: Radiation shielding produced by mini-magnetospheres
Abstract:

The  deployment  of  a  mini-magnetosphere  (or  magnetic  bubble)  around  a  spacecraft  has  recently  been  proposed  as  a  means  to  couple  energy  from  the  solar  wind  to  provide  in-space  propulsion.  In  so  doing  mini-magnetospheric  plasma  propulsion  (M2P2)  would  have both high specific propulsion and high thrust while requiring only modest (kW/unit) power levels to sustain the mini-magnetosphere.  In order to obtained sufficient thrust for a manned mission, the mini-magnetosphere is anticipated to extend out to several 100 km to a few thousand km in radius, possibly supported by several units using a total of ~ 100 kW.  At  this  size,  the  mini-magnetosphere  has  the  potential  for  not  only  deflecting  solar  wind particles, but also the energetic particles that comprise galactic cosmic rays (GCRs) and solar energetic particle (SEP) events. These energetic particles provide a significant radiation  hazard  for  any  extended  manned  mission  in  space.  This  paper  presents  initial  design characteristics for using an M2P2 system as a radiation shield. Each unit consists of  a  magnet  with  a  radius  of 10 – 20 cm, with strength of a few kilogauss to possibly a Tesla.  Embedded in each magnet is a plasma source that is used to expand the magnetic field.  It  is  shown  that  the  magnetic  field  fall  off  approaches  1/r  as  the  plasma  energy  density  approaches  the  magnetic  energy  density.  The  effectiveness  in  shielding  as  determined by the integral of B×dr can be more than an order of magnitude larger than the  magnet  by  itself.    Pulsed  operation  of  the  system  is  used  to  prevent  modification  of  spacecraft   trajectory   and   prevent   build   up   of   radiation   belts   within   the   mini-magnetosphere.

This was initially studied as a low-thrust propulsion method. That is far too slow for a human mission to Mars, you would need traditional thrust. But thrust does have to be taken into account for accurate navigation. I'm interested in this for radiation shielding. The last sentence of the abstract mentions pulsed operation to prevent build up of radiation belts. I ask why not let them build up? A mini-magnetosphere works by a contained plasma bubble that deflects solar plasma, and radiation belts are formed by solar plasma getting trapped and increasing the density of the plasma bubble. Isn't that a good thing? Wouldn't that make the plasma bubble more effective?

Could we get the authors of this paper interested? CubeSats are relatively affordable, and SpaceX launch vehicles have dramatically reduced cost. Could we build a small prototype or two to test this technology. Ideally outside Earth's magnetosphere. Bow shock of Earth's magnetosphere is 6 to 10 times Earth's radius. Earth's equatorial radius is 6,378.1 km so an orbit 20 times that would be 127,562 km above the Earth. Orbit that high is well above geosynchronous, it's about 1/3 the way to the Moon. It would ensure the satellite is outside Earth's magnetosphere for the sunward half of it's orbit. The CubeSat could carry a deployable nanosat that could fly through the CubeSat's mini-magnetosphere with instruments to measure it.

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#669 2021-02-22 14:45:21

tahanson43206
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Re: Large scale colonization ship

For RobertDyck re #668

Nice follow up! Thanks!

SearchTerm:magnetosphere mini-magnetosphere RobertDyck immediately above

***

Could we get the authors of this paper interested?

Let's try ...

SpaceNut ... Are you OK with an inquiry of the authors of the paper RobertDyck cited?

For RobertDyck .... In order to answer the question of structure of the vessel, I'll have to go to the source.

Just FYI ... I'll be looking for evidence my suggestion of extending the central shaft of the Large Ship forward (anti-Sunward) would make sense.  Perhaps your initial hammerhead design is sufficient.  From my perspective, it is unknown at this point.

I like your suggestion of building up the radiation belt around the vessel.  It seems to me the more particles in that region (away from the people) the better.

(th)

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#670 2021-02-22 17:50:49

SpaceNut
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From: New Hampshire
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Posts: 29,215

Re: Large scale colonization ship

The magnetic field is something which was in the cev orion information and satelite low frequency have be shown to be moving the radiation belts higher around earth.

Found it
If we do not have 20 cm of water content for radiation there may be the chance for this
post reference page which GW does quote...

1*pDybSxlxPQNRiCF7EFIh0A.png

Radiation amount type risk mitigation

I suspect that recovery or recycling will be low on the first mission concepts but where it applies  Mars Homesteads colony plan to recycle waste

Much of the base camp comes from Deep Space Gateway; a bad joke by NASA? or LOP as some at Nasa call it.

esa-nasa-jaxa-russia-canada-lunar-gateway-concept-diagram-modules-hg.jpg

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#671 2021-02-22 18:34:17

tahanson43206
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Re: Large scale colonization ship

For RobertDyck re paper cited in Post #668

Further work needs to look at the final solution after multiple pulses to provide that the desired level
of magnetic field of 1 Tm can be achieved along the bulk of the mini-magnetosphere. This paper only
considers two pulses, but the evidence suggests a continued building of the magnetic field. As such there
is potential for providing GeV particle shielding through mini-magnetospheres. This shielding will
required about 100 kW continuous power to support the mini-magnetosphere.
Acknowledgements
This work was supported by NASA MSFC grant NCC8-231 to the Univ. of Washington.

Thanks for providing the link to this interesting paper.

The power requirement seems reasonable to me, considering the power requirements of the Large Ship itself.

If I understand the paper correctly, the magnetic field intended to deflect oncoming charged particles is maintained at a distance through the presence of plasma fed into the field.  I'm unclear on the implications of continuous vs pulsed operation, and figure that a lot more modeling (and some real life testing as you suggested) would be helpful.

A concern I have (without any particular basis for it) is how life inside the vessel would be impacted by the presence of such a large magnetic field.

I wasn't able to glean much from the paper regarding magnet size ... the sizes quoted seemed appropriate for a small vessel on the order of a probe.

SearchTerm:magnetic shield proposal see RobertDyck Post 668 above.

For SpaceNut re #670

The paper cited by RobertDyck includes mention of the influence of the Earth's magnetic field on the performance of a test of the concept.  The Earth's field would certainly be present in LEO, but it would be less and less of a factor as the Large Ship moves away from Earth.

(th)

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#672 2021-02-23 19:26:25

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 29,215

Re: Large scale colonization ship

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#673 2021-02-24 06:43:28

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 17,907

Re: Large scale colonization ship

For SpaceNut re #672 ... thanks for bringing that impressive topic from 2012 back into view!  RobertDyck, Void, SpaceNut and others were in good form when working together on that topic.  I noted contributions by members who have not been present lately.

In my first scan, it looked to me as though the members were tackling the challenge of providing a magnetic field for Mars itself.  There might be something in that series of posts that would be helpful to RobertDyck in protecting his large ship.

(th)

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#674 2021-02-25 06:46:55

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 17,907

Re: Large scale colonization ship

For RobertDyck re Large Ship ...

To this point, we seem to be looking for qualified help in places where the results are not impressive.

To the need for a master chef and an engineer to help with testing the rotation hypothesis with a real flying (in space) model, we seem to have a need for an engineer qualified to evaluate the various proposals for generating a magnetic field of sufficient strength to protect the passengers and crew.

SpaceNut is the only member of the forum who has actually posted invitations to help with work in this forum.

All members of the forum are potentially capable of assisting, by writing letters-to-the-editor for their local media outlets.

The members could also help by drafting example announcements that could be copied into letters-to-the-editor.

(th)

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#675 2021-02-25 09:26:43

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 29,215

Re: Large scale colonization ship

Those that have there own blogs can also put up content to gain exposure for this quest as well.

example but add in more specifically what talent we are looking for as each project is different.

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.

even repost of answers to your blogs are welcome resposes to the need...

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