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.

#626 2021-01-26 22:25:20

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 17,133

Re: Large scale colonization ship

For RobertDyck re #625

I can only assess the situation from comments GW Johnson has made from time to time, but I get the impression he would not be wanting to run software for trajectory calculations on his own computer.  What he ** might ** be willing to do is to look at results others come up with, and using his own tried and true methods, confirm them or falsify them.

However, if you ** are ** interested in digging into this a bit, I'm game to go as far as I can .... here is a web site with a number of (I believe) Open Source software packages for space mission planning.

Some look quite promising.

I understand your preference for the free return fast flight to Mars option for the Large Ship.

In contrast, I am interested in finding a trajectory that puts non-human bulk cargo on Phobos without any velocity adjustment other than fine tuning the trajectory in the form of mid-course corrections, preferably using an ion engine.

The Hohmann transfer trajectory (I'm repeating this, not for you, but for a reader who chances upon this post after a search) has the advantage that it puts a space craft at Mars when Mars arrives, using the least energy possible.  It has the distinct disadvantage that it places the spacecraft in the location where Mars is approaching from behind the spacecraft at a significant velocity.  The spacecraft has to accelerate to stay ahead of the planet.  Meanwhile the planet is pulling the spacecraft towards it, so the spacecraft has to accelerate some more to avoid a collision.

I am looking for a solution that invests energy at departure from Earth sufficient to place the spacecraft right at the surface of Phobos when Phobos is receding from the approaching spacecraft.   This would yield an optimum solution to Void's Ballistic Package Delivery concept.

https://www.nasa.gov/smallsat-institute … sign-tools

(th)

Offline

#627 2021-01-27 04:10:48

Calliban
Member
From: Northern England, UK
Registered: 2019-08-18
Posts: 3,425

Re: Large scale colonization ship

RobertDyck wrote:

We need a trajectory specialist. Using trajectories from Mars Direct, a trip to Mars will take 6 months, wait in Mars orbit 14 months, then return to Earth. Once in Earth orbit it will be a rush to offload passengers and cargo, reload the next group of passengers and cargo for Mars, load propellant and food and supplies, then you're off. That's far from ideal.

Ideal would be travel to Mars, remain in Mars orbit long enough to offload passengers and cargo, refuel, load food and parts for repair and maintenance, and enough time left to do repairs or maintenance before returning to Earth. Time between trips should be spent in Earth orbit, not Mars orbit. While waiting for planets to align, the ship could be used as a space hotel for tourists.

So how do we calculate a set of trajectories that do that?

It will be energetically much cheaper to source all necessary consumables from Mars.  If the ship is propelled by ionic propulsion with ISP 5000s, then argon propellant taken from the Martian atmosphere should be sufficient for both the trip from Mars to Earth and back again.  The argon can be delivered to the ship whilst in LMO by SSTOs from the Martian surface.  The same with food, water, air and other victuals.

In fact, an early business opportunity on Mars could be the production of consumables, raw materials and simple manufactured goods for use in Earth orbit.  I don't think we would use your passenger ship to carry out that trade, but it would seem to make sense to source the necessary propellant and other consumables needed for both legs of the journey on Mars.  That only works with high ISP propulsion of course.

Whilst it is difficult to imagine a strong business case for exporting anything from Mars to Earth surface; the opportunities are much stronger for export to Earth orbit or the lunar surface.  As soon as there exists a flourishing colony on Mars, anything that we intend to build in Earth orbit should make use of Martian materials to the greatest extent.  This probably includes space station modules for example, with complex manufactured parts being lifted from Earth.  It would certainly include air, water and food.  All the propellant needed to deliver the components and return the tug to Mars orbit, should be sourced from Mars as well.

Ultimately, for any space venture, we would expect Earth to provide design services, high tech but low mass components and the necessary crew.  Mars will provide consumables, propellant and low tech, high mass components.  Assembly will be in Earth orbit.

Last edited by Calliban (2021-01-27 04:33:43)


"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."

Offline

#628 2021-01-27 07:05:43

RobertDyck
Moderator
From: Winnipeg, Canada
Registered: 2002-08-20
Posts: 7,811
Website

Re: Large scale colonization ship

tahanson43206,
It's difficult to get any better. With Hohmann, the aphelion is right at Mars orbit so direction is the same direction that Mars travels. Slightly faster transit could achieve velocity at Mars orbit closer to Mars itself, but any transfer orbit with higher energy and therefore faster transit then Hohmann would have apohelion farther from the Sun than Mars. That means at Mars rendezvous the direction of the craft is not exactly the same as Mars. Furthermore, approach to Mars will result in Mars gravity accelerating the craft toward the red planet. So there will always be some velocity.

One great advantage of Mars is its atmosphere. A craft traveling to Phobos, such as a robotic fuel tanker, could use aerocapture to enter Mars orbit, then approach Phobos (or Deimos) with very little relative velocity.

Offline

#629 2021-01-27 07:29:41

RobertDyck
Moderator
From: Winnipeg, Canada
Registered: 2002-08-20
Posts: 7,811
Website

Re: Large scale colonization ship

Calliban,
Yes, we are in agreement. The business plan for the large ship is to source food for transit in both directions from Mars. The only food from Earth would be luxury items. Source parts for maintenance and repair from Mars. Return propellant comes from Mars or a Martian moon. Propellant for the outbound flight comes from a propellant depot in Earth orbit.

Source for that depot comes from a C-type asteroid. One astronomer claimed all asteroids closer to the Sun will have boiled off its volatiles long ago. To still have ice the asteroid must be the distance as Mars or farther. But surface spectra of both Martian moons are the same as C-type asteroids; they appear to be captured asteroids. This means ideal source of propellant may be Mars' moons. Again, we can use Mars atmosphere for aerocapture for a robotic tanker arriving from Earth to pick up its next load of propellant. Once in an Earth orbiting depot, that propellant can be use for various purposes.

Offline

#630 2021-01-27 08:36:04

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 17,133

Re: Large scale colonization ship

For RobertDyck and Calliban (and for SpaceNut keeping a watchful eye on developments) ...

Please write up a draft of a request for assistance with development of a business plan (or plans) for the Large Ship venture.  This doesn't need to be a "chicken-egg" dilemma.  The entire plan can be designed as a piece, and then constructed by multiple teams operating in parallel.

(th)

Offline

#631 2021-01-27 16:59:06

Calliban
Member
From: Northern England, UK
Registered: 2019-08-18
Posts: 3,425

Re: Large scale colonization ship

If I am reading the Delta V map presented in the Wiki link correctly, the dV from LEO to LMO is ~7.2km/s, taking full advantage of the Oberth effect, using high thrust propulsion. 
https://en.m.wikipedia.org/wiki/Delta-v_budget

From the link: 'Electric propulsion vehicles going from Mars C3 = 0 to Earth C3 = 0 without using the Oberth effect need a larger Delta-v of between 2.6 km/s and 3.15 km/s.[12] Not all possible links are shown.'

Using electric propulsion significantly increases the dV required to reach Mars.  If dV increases to say 10km/s in either direction, then total dV for a round trip from Mars to Earth and back to Mars again, would be ~20km/s.  Applying the rocket equation for an exhaust velocity of 50km/s (ion propulsion) and dV of 20km/s; yields a mass ratio of 1.49.  In other words, if we wanted to fly from Low Mars Orbit to Low Earth Orbit and then back again without taking on any fresh propellant in Earth orbit, but with payload mass the same in both directions; the starting mass of the ship in Low Mars Orbit, must be 33% propellant by mass.  A fully loaded ship weighing 1000 tonnes, would be carrying at least 330 tonnes of argon propellant.

The total dV required to deliver materials from Mars surface to LEO, is about 50% higher than the dV required to reach LEO from Earth surface.  However, the overall propellant mass required is substantially lower, because most of the dV can be carried out using electric propulsion, with a factor 10-15 improvement in exhaust velocity compared to chemical rockets.

Last edited by Calliban (2021-01-27 17:14:31)


"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."

Offline

#632 2021-01-27 21:13:54

RobertDyck
Moderator
From: Winnipeg, Canada
Registered: 2002-08-20
Posts: 7,811
Website

Re: Large scale colonization ship

Try this. Earth to Mars transfer in 6 months, ∆V 4.34 km/s injection. At 9,000 second Isp that works out to 4.8% departure mass propellant. Arrival at Mars requires manoeuvring propellant only because it uses aerocapture. For a giant ship this size, does that explain what I'm trying to do?

::Edit:: For a 1,000 tonne ship that's 48 tonnes departure propellant. Of course achieving 9,000 seconds requires heating uranium to plasma.

Last edited by RobertDyck (2021-01-27 21:31:50)

Offline

#633 2021-01-29 20:53:37

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 17,133

Re: Large scale colonization ship

For RobertDyck ... I'm hoping this topic is broad enough to include psychology as well as the physical sciences ...

The article at the link below is about the Chinese submarine fleet.

My guess is that the US (and NATA navies) have dealt with this issue as well.

I've quoted a line about a recent (2013) upgrade to US procedures.

https://www.yahoo.com/news/chinese-sail … 11659.html

This important program, known as the embedded Mental Health Program (eMHP), was later extended to additional surface vessels and appeared to be similarly effective.

An eMHP for the Navy's submarine force was piloted in 2013 in Norfolk, Virginia and showed positive results, reducing annual unplanned losses from 22 to 2 by 2016, when the program was expanded to provide greater mental health support to the larger submarine force.

I bring this up because there are a number of inputs from a number of sources suggesting that selecting people who can handle the challenges of flight away from Earth is important.

The problem may be less severe if the number of passengers and crew is large (as would be the case for RobertDyck's Large Ship), and the nature of duty ** may ** be less stressful than is the case with military submarine service.

(th)

Offline

#634 2021-01-30 00:22:52

RobertDyck
Moderator
From: Winnipeg, Canada
Registered: 2002-08-20
Posts: 7,811
Website

Re: Large scale colonization ship

Mental health is an issue, but obsessing over mental health makes everything worse. When I was a child, you were told to just "buck up" and take it. Whatever the issue.

As for space, when I was a child, only rich children got a room to themselves. Normal human beings had to share a bedroom with siblings. I had a room with my brother. My mother described her early childhood in the late 1930s, the tail end of the Great Depression. Their house was basically a garage with a lean-to addition. My parents drove us to visit my father's parents for two weeks every summer, on their farm. I was a preschooler in the 1960s, but my grandparents farm house was built in the 1950s. The old house was still there, just vacant. My father grew up in a large single room, with a separate bedroom for his parents. The house was attached to the barn. One great room for everything: living room, kitchen, bedroom. My father was one of 11 children; they slept on the floor. Again, late 1930s. Compared to how my parents grew up, the house I grew up in was luxurious.

I've run into people who claim everyone needs a place to be alone. They claim a bunk with a curtain isn't enough. Well, if they can afford a private cabin, they buy a ticket for one. Most people will not have that much money. The cheapest ticket will get you a bunk in a cabin with 5 strangers; total 6 people including yourself. A family could book an entire cabin, but expect parents and children will share a single cabin. A standard cabin is large enough for 3 bunk beds, each with 2 bunks. Compare to an aircraft carrier, and I mean modern American supercarrier. Crew there get a bunk with 3 bunks high, and storage under the mattress, plus a locker. I visualize the bottom bunk as a "captain's bed", meaning 2 rows of drawers under the lower bunk. Plus the same under-mattress storage, but no locker. Instead of the locker, you get one of the rows of drawers. Each cabin has a washroom (head) with one toilet, sink, and small shower. Bunks the same width as "single" beds, not "twin". That means 30" wide bunks. The shower is the same size as width of a bunk, so 30"x30" (2.5' x 2.5'). Aircraft carrier bunks have a curtain, so the bunk provides a private space for the individual crew member. Bunks on a cruise ship typically don't, but our large spaceship could.

TV news video (5 minutes): Life on an aircraft carrier

In addition to cabins, the ship will have:

  • dining rooms: one large with 300 seats, two medium with 50 seats each, one "fine dining" with only 20 seats. Fine dining meals cost extra per meal, included with a luxury cabin.

  • bar, configured as a brew pub. That means beer, wine, vodka, and even gin made locally in vats behind the bar. A window separates the bartender's space from the brewery.

  • two observation decks. Each with transparent "greenhouse style" walls and ceiling. Single piece like a fighter jet canopy? With park benches and potted plants. One observatory with juniper, the source of juniper berries for the bar. The other with dwarf orange trees, producing full-size oranges. Perhaps telescopes for passengers to look at the stars, although they would have to track quickly due to ship rotation.

  • one Mars simulation room. With airlock and spacesuits. Same pressure and gas mix as the surface of Mars. After the first trip, the floor covered in a thin layer of real Mars dirt.

  • gymnasium with exercycles, treadmills, weight machines. To keep equipment relatively light, instead of weights lifted by pulleys, think "Blowflex". I'm currently thinking a two-story gym with running track on the second level, and inside the running track is just open to the lower level. This is how the downtown YMCA is configured in my city.

  • zero-gravity hub will be the foyer to accept passengers when they arrive. During transit, that can be a zero-G play room. Cargo hold is aft the the zero-G hub, but that's off-limits to passengers.

  • also normally off-limits: dispensary (sickbay), bridge, kitchens, laundry, 3 greenhouses.

Compared to a normal spacecraft, this a lot of space.

Passengers will also have Wifi, with laptop or tablet. The ship will have an onboard server with movies and TV shows. No regular schedule, instead watch whenever you want. A library of digital documents to read, both fiction and non-fiction. Basically think Netflix and YouTube, Wikipedia, Kindle, and PDF documents for journals like Science, Nature, Journal of Geophysical Sciences, etc. Ships server could mirror the majority of Wikipedia and major parts of YouTube, so not just like them, actually is them.

Organized activities like science lectures of what Mars will be like, or "tour of the sky" in an observation deck by an astronomer, book club meeting, toastmasters, etc. Classes for skills you will need on Mars.

One difference between navy ship vs this ship: no officer's mess. I'm thinking crew including the Captain will eat meals in a dining room like any passenger. Although I've seen movies that depict eating at the Captain's table to be a privilege. I considered "fine dining" to be a place where rich passengers can eat meals separate from regular passengers. If they feel they have to be separated. The Captain could arrange a meal in the main dining room with certain invited passengers as an "event".

We've had military members tell us they've served on isolated remote posts for months at a time.

Offline

#635 2021-01-30 03:55:55

RobertDyck
Moderator
From: Winnipeg, Canada
Registered: 2002-08-20
Posts: 7,811
Website

Re: Large scale colonization ship

In post #450, I showed you the floor plan of a SpaceX Starship. That's the real alternative. I have said before, this is a transportation spaceship. It isn't a luxury cruise ship. Don't expect recreation like a Caribbean cruise ship. Alternatives: Apollo LM sleeping positions
WOTMa12.hammocks.jpg
Apollo_LM_crew_rest_positions.jpg

Offline

#636 2021-01-30 07:57:09

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 17,133

Re: Large scale colonization ship

For RobertDyck re #634

Nice summary! 

SearchTerm:LargeShip summary of accommodations compared to military vessels and civilian cruise ships (see Post 634 above)

***

An alternative I'm trying to introduce is to provide a service to Elon ... his ships are not and never will be designed for passenger service over six months.

You have imagined an alternative that Elon could contract with to provide safe, "comfortable" accommodations for his passengers and crew.

Your ship would accommodate 10 Starships at the rate of 100 passengers per Starship.

They would assemble at your location in LEO, and the entire fleet of 10 Starships and your Large Ship would depart LEO.

All vessels would receive "first stage" pushes by space vehicle tugs designed for the purpose.  That way all vehicles including Large Ship would be able to hold onto propellant and other needed supplies for the trip, and for arrival at the destination.

This scenario would allow you to be able to afford to decelerate the Large Ship at Mars so you don't have to risk law suits for damages caused by your vessel descending onto the top of the first settlement on Mars due to poorly designed shields and inadequate bracing of the superstructure to withstand the forces that would act upon the vessel if it were flown through the atmospheres.

At Mars, all of Elon's passengers and crew would return to their Starships, which would independently fly their own trajectories to land on Mars.

Your Large Ship would slow more easily without the mass of the passengers, and would enter orbit around Mars with just its crew on board, to await a return passenger manifest.

By following this business concept, and with a bit more work on your part to assemble a team to help you with engineering details, you could offer your service to Elon.

(th)

Offline

#637 2021-01-30 10:44:21

GW Johnson
Member
From: McGregor, Texas USA
Registered: 2011-12-04
Posts: 5,459
Website

Re: Large scale colonization ship

Hohmann transfer to Mars (or to return home) averages 8.6 months one way.  If you use the 2-year period free return abort orbit as the faster trajectory option,  it cuts your one-way travel time roughly in half.  That's still a long time to endure confinement and the adversity of zero-gee operations,  but it's a lot shorter than 8.6 months.  You have to pay for it,  though.  The departure delta-vee from Earth orbit is larger,  and your velocity relative to Mars at arrival is a lot higher,  too.  In point of fact,  that is where Spacex's entry interface speed of 7.5 km/s for Starship at Mars came from. It's closer to only 5.5 km/s from Hohmann.

GW


GW Johnson
McGregor,  Texas

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

Offline

#638 2021-01-30 12:24:48

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 17,133

Re: Large scale colonization ship

For GW Johnson re #637

This is RobertDyck's topic, and he has expressed interest in the two year flight with free return, which (as I recall) you have described in some detail in earlier posts.

RobertDyck has confirmed on multiple occasions that he is determined to slow down using aerobraking through the atmosphere of Mars, and I think it can be assumed he will adhere to that plan.

However, RobertDyck will have competition. 

It is possible at least ONE of RobertDyck's competitors will decide to spend propellant to match orbits gently with Mars.

A recent post about the first of the planned Mars probes to arrive at Mars (the Arabian one) will expend a third of its mass to achieve an elliptical orbit with a (planned) eccentricity such that they will be able to observe the planet from both great height and much lower in.

My question for you is ... does the mass percentage seem about to right to you, for any vessel approaching Mars on Hohmann, and NOT planning to fuss with aerobraking?

(th)

Offline

#639 2021-01-30 14:25:33

RobertDyck
Moderator
From: Winnipeg, Canada
Registered: 2002-08-20
Posts: 7,811
Website

Re: Large scale colonization ship

tahanson43206 wrote:

you could offer your service to Elon.

I applied for work with SpaceX in 2016. As a computer network technician in Texas. I was afraid they would be worried about ITAR, so in my application pointed out I had registered as a contractor with NASA, and got on NASA's short list a couple times. One was a bid to replace the computer for the diagnostic workstation for communication equipment on Space Shuttle orbiters. That one required ITAR clearance to receive technical documents about Shuttle. I did that: I first got Canadian equivalent to ITAR for my house here in Canada, then using that got actual American ITAR clearance. I did it, no one else. I applied and I got it. Furthermore, I have worked in the US a couple times. In 1996 I worked for Allied Signal Fibres, in the plant location where Spectra fibre is made; one application of Spectra is body armour for American army soldiers. And in 1999 I worked for Miami-Dade County, solely responsible for the computer system for one tax. A county tax, but still. And that job in 1999 required me to get "Reliability" level security clearance through the FBI. I got that. And I applied for a job with a contractor bidding on something with the Canadian federal government; for that I got "Reliability" level security clearance for Canada. For the Canadian one, they normally have the RCMP do security clearance check (Canadian federal police), but in my case CSIS did the check. That's Canadian equivalent to the CIA. The contractor never said exactly which government department I would work for, but it's interesting CSIS did the check. Security clearance is good for 10 years, the FBI clearance has expired, but the Canadian one was 2012 when I applied with SpaceX in 2012 it was still current/valid. And it's still valid today. I mentioned all this in my job application to SpaceX. They didn't reject me right away, but while I was waiting for a reply, Elon Musk gave his first presentation for Starship at the International Astronautical Conference in Mexico. The ship had a different name then. At the end he took questions; one woman asked why he doesn't hire any non-Americans. His answer was ITAR. The following morning I got a reply from SpaceX HR; they politely rejected my application due to ITAR. So effectively, Elon himself rejected my application.

After all my long explanation, they rejected me due to ITAR anyway. The rejection letter said that if I ever move to the US, I could re-apply. But that's the problem: I'm Canadian, so the only way to get a Green Card is for an employer to sponsor me. Believe me, I checked. The two times I did work in the US, my employer sponsored me for a "TN" work visa. "TN" stands for "Temporary NAFTA". Maximum period of a work visa is 3 years, but my first contract was for 6 months so Immigration and Naturalization Services (INS) made it expire the same day as my contract. The second job was a 12 month contract; again INS made my work visa expire the same day as the contract. Under US law, when my work visa expires, I am required to return to Canada. For the second contract, they terminated me after 9½ months, so I could have stayed until my work visa expired, but Miami is expensive. I stayed to the end of the month, spent my time using the telephone and internet to find a job, then returned to Canada. My job application with SpaceX was for a job in Texas, so SpaceX could have sponsored me for permanent residency status (Green Card). That's how it's done; I can't just move to the US. First an American employer must provide a job offer, then they must sponsor me for either temporary work visa or permanent residency, then and only then can I move to the US.

By demanding that I move to the US *BEFORE* applying for work with SpaceX, they've created a chicken-and-egg problem.

Offline

#640 2021-01-30 14:49:02

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 17,133

Re: Large scale colonization ship

For RobertDyck re #639

Thank you for your reminder of your application difficulty with ITAR .... I've been troubled about that policy all along ... I'm not sure what policy would be better for the nation in a dangerous world, and don't feel qualified to guess, but I've read a number of stories like yours. 

To get off on a tangent a bit... someone wrote an article recently about the problems the United States creates for itself due to security worries.   The gent who created the Chinese space program and ran it for many years was ejected from the United States AFTER he had shown great leadership capability inside the US. As I recall, he had come here as a student, and was perfectly happy staying here.

However, to get back to the main point, which is the proposal your concept for a large passenger vessel could be a major benefit to Elon ...

In the scenario I am considering here, the Large Ship would NOT be a SpaceX project.  On the contrary, it would be a service offering with which he would contract, just as (I'm sure) he is doing with countless vendors whose services do not to be done by SpaceX employees.

I recognize that Elon prefers a vertically integrated organizational structure which reduces dependencies on outside agencies to the minimum, but I'll bet he doesn't avoid hiring contractors where the activity is not in the mainline of SpaceX objectives.

My suggestion is that there is a business case to be made for delivery of passenger service to Elon so he doesn't have to follow through on the (to me ridiculous) idea of sending 100 people to Mars in one of his tin cans.

Now I'm going to digress again ....

Gene Krantz gave a talk a few years ago, about the history of the US space program ... I've seen the presentation before on CSPAN, and they ran it again a couple of nights ago .... In the portion I caught, Mr. Krantz was telling the military students in the audience about the days before Mercury, and the (to me still) unbelievable good luck of the Canadians giving up on a very advanced aerospace program, disbanding the organizations involved, and even destroying the aircraft that had been created.  To my ears when I first heard about it, and still today, that was one of the must foolish decisions ever made by a government, right up there with Chinese burning all the ships that had explored the world in the 1500's or thereabouts.

At any rate, the very talented, experienced and capable employees of the former Canadian enterprise were available, and the US space program snapped up a number of them.  Krantz went on to talk about the challenges of melding three very different cultures in what became the US space program.

Now, with that digression out of the way, I am wondering if the gas is gone from Canada, or if they (the government AND the people) might be willing to take on the challenge of building your Large Ship.  I have no way of knowing, but hope that it might be possible.

This could be a collaborative activity in which the US plays no role whatsoever.

Canada remains part of the UK association to some extent, and I'm (pretty sure) is still on good terms with the Europeans.

If you (as the instigator of all this) can find a sympathetic ear somewhere in Canada, civilian, governmental or ???, there might be some interest is seeing what can be accomplished.

(th)

Offline

#641 2021-01-30 15:53:01

RobertDyck
Moderator
From: Winnipeg, Canada
Registered: 2002-08-20
Posts: 7,811
Website

Re: Large scale colonization ship

GW Johnson wrote:

That's still a long time to endure confinement and the adversity of zero-gee operations

This ship uses artificial gravity. It is not zero-gee.

Offline

#642 2021-01-30 20:17:33

louis
Member
From: UK
Registered: 2008-03-24
Posts: 7,208

Re: Large scale colonization ship

I thought argon was an inert gas.  Can it be used as a fuel/propellant? Of course we might be able to simply pick up methane clathrates from the Mars surface.

It would likely make sense to transfer a lot of stuff from Mars to LEO but I guess the Moon would be a competitor.


Calliban wrote:
RobertDyck wrote:

We need a trajectory specialist. Using trajectories from Mars Direct, a trip to Mars will take 6 months, wait in Mars orbit 14 months, then return to Earth. Once in Earth orbit it will be a rush to offload passengers and cargo, reload the next group of passengers and cargo for Mars, load propellant and food and supplies, then you're off. That's far from ideal.

Ideal would be travel to Mars, remain in Mars orbit long enough to offload passengers and cargo, refuel, load food and parts for repair and maintenance, and enough time left to do repairs or maintenance before returning to Earth. Time between trips should be spent in Earth orbit, not Mars orbit. While waiting for planets to align, the ship could be used as a space hotel for tourists.

So how do we calculate a set of trajectories that do that?

It will be energetically much cheaper to source all necessary consumables from Mars.  If the ship is propelled by ionic propulsion with ISP 5000s, then argon propellant taken from the Martian atmosphere should be sufficient for both the trip from Mars to Earth and back again.  The argon can be delivered to the ship whilst in LMO by SSTOs from the Martian surface.  The same with food, water, air and other victuals.

In fact, an early business opportunity on Mars could be the production of consumables, raw materials and simple manufactured goods for use in Earth orbit.  I don't think we would use your passenger ship to carry out that trade, but it would seem to make sense to source the necessary propellant and other consumables needed for both legs of the journey on Mars.  That only works with high ISP propulsion of course.

Whilst it is difficult to imagine a strong business case for exporting anything from Mars to Earth surface; the opportunities are much stronger for export to Earth orbit or the lunar surface.  As soon as there exists a flourishing colony on Mars, anything that we intend to build in Earth orbit should make use of Martian materials to the greatest extent.  This probably includes space station modules for example, with complex manufactured parts being lifted from Earth.  It would certainly include air, water and food.  All the propellant needed to deliver the components and return the tug to Mars orbit, should be sourced from Mars as well.

Ultimately, for any space venture, we would expect Earth to provide design services, high tech but low mass components and the necessary crew.  Mars will provide consumables, propellant and low tech, high mass components.  Assembly will be in Earth orbit.


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

Offline

#643 2021-01-30 20:19:23

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 28,866

Re: Large scale colonization ship

Louis, Argon is for the ION propulsion alone with Krypton, Neon and a few others to be used but its not for a rocket engine...

Offline

#644 2021-01-30 20:29:09

RobertDyck
Moderator
From: Winnipeg, Canada
Registered: 2002-08-20
Posts: 7,811
Website

Re: Large scale colonization ship

louis wrote:

I thought argon was an inert gas.  Can it be used as a fuel/propellant?

Noble gasses (inert gas) can be used by ion engines. They ionize the gas, then use a screen with electrostatic charge to accelerate the ionized gas. An ion engine requires inert gas. But Mars atmosphere has only 1.6% argon, and less than 1% of Earth's total atmospheric pressure. So not much. There's more ice in the ground. Methane is made with CO2 and water. Liquid hydrogen is all from water. There's lots of ice in the solar system.

NASA's NSTAR ion engine used on Deep Space One used Xenon gas. You can also use Krypton, but Xenon is heavier so produces more thrust for a given electric charge. An ion engine can use argon, but will require more electric power. It's also been tried with Bismuth; a solid at room temperature.

Offline

#645 2021-01-31 06:20:25

RobertDyck
Moderator
From: Winnipeg, Canada
Registered: 2002-08-20
Posts: 7,811
Website

Re: Large scale colonization ship

tahanson43206 wrote:

...Canadians giving up on a very advanced aerospace program, disbanding the organizations involved, and even destroying the aircraft that had been created.  To my ears when I first heard about it, and still today, that was one of the must foolish decisions ever made by a government, right up there with Chinese burning all the ships that had explored the world in the 1500's or thereabouts.

That was the Avro Arrow. The A. V. Row company, known as "Avrow", designed and built the Arrow. It was the most advanced fighter jet for it's time. I've run into some Americans who claim "no one even conceived of supercruise in the 1950s". Well, the Canadian air force did, and contracted Avrow to build it. The Soviet Union flew the first Tu-95 bomber (Bear bomber) in 1952. The world was shocked. The Canadian air force wanted an all weather interceptor that could shoot it down. Air force generals drafted requirements in 1953. When engineers first saw those requires they cried "It's impossible!" The complained, got drunk, cried in their beer. In the morning when they sobered up, they got to work and built it. Requirements called for supercruise at 50,000 feet at mach 1.5, and top speed in flat level flight at mach 2.0. What they built was capable of top speed mach 2.5 in flat level flight at 50,000 feet. Of course that's with afterburner, so fuel won't last long. The purpose of supercruise is so fuel will last long enough to reach the target, then return safely. Prototype mark 1 used the engine from an existing fighter; only capable of supercruise at mach 1.02. Production aircraft were to use a new engine. One prototype aircraft was built with the new engine, serial# 205, called mark 2. It was production configuration. The aircraft was fully complete, but engines not installed. The engines were fully complete as well, sitting right behind the aircraft. It would have taken technicians 8 more hours to install the engines. That's when the government cancelled it, and cut up the prototype.

The US government didn't like the fact Canada built a better fighter jet than anything the US could build. American aircraft companies felt threatened. The US government pressured NATO allies to not purchase Canada's new fighter jet. But Canada has 1/9th the population of the US. People often say 1/10th, but it's actually 1/9th. Was then and still is now. That means Canada's economy is that much smaller. We can't afford a fighter program on our own. The business model always included selling fighter jets to our NATO allies. Both the manufacturer and the Canadian government expected to sell aircraft to the US. Not only did the US government refuse, but pressured all our NATO allies to refuse as well. France ordered jet engines from the Arrow; they were so powerful that installing them in Mirage fighters would have been a major upgrade. But nothing else. Without customers to purchase the plane, Canada couldn't afford it. This became a major political issue. The Liberal Party of Canada was the government that approved the project. I should add, the Liberal party is not exactly "liberal" in the sense that Republicans use the word. The Liberal Party of Canada is roughly equivalent to the Democrat Party. Not exactly, but you get the idea. The other major party at that time was the Progressive Conservative party, now simply called the Conservative Party of Canada. They criticized the government for spending so much money. One plank of their election campaign was to kill the project. Once elected, they didn't kill it right away, but eventually did.

Ps. The government gave the order to destroy all documents, erase all computer tapes. However, a copy of all blueprints has been retained. And all in-flight test data has been retained too. Government in 1959 ordered it all destroyed, but a copy was hidden and retained. I could tell that story if you want.

Canadians were shocked for generations. I wasn't born all this happened, but heard a lot about it. When I expressed interest in aerospace engineering as a child, people would tell me to forget it. They would cite the Avrow Arrow; that any Canadian aerospace venture is doomed to failure. No one can get work in that field. Forget it.

tahanson43206 wrote:

...I am wondering if the gas is gone from Canada, or if they (the government AND the people) might be willing to take on the challenge of building your Large Ship.  I have no way of knowing, but hope that it might be possible.
...
If you (as the instigator of all this) can find a sympathetic ear somewhere in Canada, civilian, governmental or ???, there might be some interest is seeing what can be accomplished.

Short answer is yes. The "gas" has gone from Canada. The Canadian Space Agency has tried to carry on. Has tried to do significant things. Citizens are kind of proud, but never expect anything big or significant. The CSA is expected to be a hanger-on, also-ran. CSA provided the arm for America's Shuttle. And another arm for ISS. Canada has a small corp of astronauts who tag along with other countries in space. I could recite the story of Radar Sat; it's interesting and Canadians like it. But it's seen as a one-off and a little thing.

I talked to Marc Garneau, Canada's first astronaut. I first met him after he retired as an astronaut, when he was president of the Canadian Space Agency. He went on to become a Member of Parliament, and is currently a cabinet minister of the Federal Government. I spoke with him many years ago, before SpaceX was founded, about a Canadian led international mission to Mars. My idea was to use Russia's big rocket: Energia. I read about it from Mars Society documents. Robert Zubrin himself first proposed using it. I told Mr Garneau that if American traditional aerospace companies want to drag their feet, slow everything down and over inflate prices, then tell them they're not invited. Mr Garneau said he was interested, but nothing happened. I spoke to another Canadian astronaut about this. He also liked it, but again nothing happened.

When Mr Garneau was president of CSA, he proposed a rover to Mars, about the size of Spirit or Opportunity; but this would be a Canadian mission. He said Canada's space partners could help on our project, instead of the other way around. I tried to support Mr Garneau's project. I spoke to a few MPs in the Liberal party when they were government. When I raised the idea, they asked how much this would cost. The Canadian Space Agency's entire budget at that time (2004-2006) was $300 million Canadian dollars per year. The rover would require increasing the budget to $450 million per year. That's an increase of $150 million per year for the duration of the project. Every MP said no. Ironically, when the other party got elected, they increased the space agency's budget to precisely $450 million per year, but no Mars rover. What did they do with that money? Now the Liberal party is in power again. They're worried about COVID-19.

This is destroying our economy. The government went into irresponsible deficits when they were elected in 2015, but now! Everyone is worried. There were huge subsidies to help people weather the lock-down, but they only lasted 6 months. There are some business subsidies, but the one for individuals is over. I don't see them spending on a big project until after COVID-19 is gone. Once it is gone, economic recovery will be a massive project.

Well, that's pessimistic. On a bright side, the CSA issued an invitation to tender to develop methods to produce food in space. With intended spin-off of producing food in northern remote communities. I intend to submit something. That's the kind of small thing the CSA is willing to do. Taking the lead for something as big as the Large Ship is beyond what they think they can do.

Offline

#646 2021-01-31 07:52:36

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 17,133

Re: Large scale colonization ship

For RobertDyck re #645

Thank you for this long, detailed, thorough and (to me impactful) summary of the Avrow story.  Gene Krantz gave the upside to the story, by stating very clearly that the team of about 50 people hired from the end of Avrow were at the heart of the organization that built and operated Project Mercury, and ultimately put men on the Moon.  It would be good to have the Canadian contribution documented.  It may actually already have been documented, because the records of the 50 folks must be stored somewhere.  And while most are now gone, there may be a few still with us.  That was 60+ years ago ... there wouldn't be many left.

SearchTerm:Avro Long Detailed Report and Commentary on Canadian aircraft company
http://newmars.com/forums/viewtopic.php … 39#p176339

Here's my eternal optimism again .... There is an entirely new generation in Canada, and the global threats are significant but different ...

If you feel up to it, and if the Canadian Astronaut is still living?

Google reported the Canadian Astronaut as Chris Hadfield ... and 8 others

Chris Hadfield

David Saint-Jacques

Jeremy Hansen

Jenni Sidey

Joshua Kutryk

Marc Garneau

That is a much younger crew, after Marc Garneau ....

They might be willing to support your Large Ship initiative ...

It would be a Canadian initiative aimed at a commercial market that does not yet exist but is likely to come into being.

You have (or would have) a chance of capturing business from Elon if you can catch him in a good mood.  I have no idea (of course) how to do that, but it makes no sense to fail to try. 

Since you already know Mr. Garneau he'd be where to start.  He's a mere 71 per Google ... born in 1949.  You could wish him a happy birthday when February 23rd comes up.

The question should be put to the entire population, it seems to me.

The idea of growing food for the northern population is ** so ** worth while!

The recent news feeds on this subject have been quite encouraging.  Apparently the business model of LED lighting for indoor high-rise growing facilities is continuing to develop around the world.  Canada has some experience with reactors, and those are the best possible source of energy for indoor growing facilities. 

You mentioned population .... Energy is at the heart of civilized living.  It seems to me talented folks would be interested in Canada for a wide variety of reasons, if there were a prospect of an ample supply of energy to support civilized living in the Northern latitudes.

This is a big ambition.  I have no idea if this is the right time for Canadians to allow themselves to think on this scale, but it is surely a question worth asking.

Good luck!

Best wishes for a series of unbelievable positive connections as you reach out.

Remember that the potential market for a safe, comfortable and rewarding flight to Mars is a global one.  Please save your austere prison ship ideas for the later years, when the world's indigent are clamoring at your door to escape Earth.

Right now the going price for a ticket to the ISS is $55 million.  Go with that as your ticket price and lay on the comforts.

(th)

Offline

#647 2021-01-31 09:47:44

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 28,866

Re: Large scale colonization ship

The number of space tourists to the ISS only 8 have been not all that many and the target is 1,000 working living settlers or colonists which are not tourist.

https://en.wikipedia.org/wiki/List_of_v … ce_Station

https://didyouknow.org/lists/spacetourists/

Offline

#648 2021-01-31 11:53:30

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 17,133

Re: Large scale colonization ship

For SpaceNut .... re #647 .... It might help to stretch vision from the near term to the foreseeable future ...

I heard a report recently that despite all the bad things happening in the world, the population is steadily increasing toward 10 billion.

What that tells me is that if we take as a given that a Job Creator comes along at the rate of only 1 per billion people, then there should be at least 10 in a few years.  The number of people alive today who can afford a $55 million jaunt into space is significant.  It is probably possible to do a search that gives some sense of the number.  I would expect to find there are at least 1,000,000 people on Earth who could afford such a trip, today.  There may well be more.

Something else to consider that (in my opinion) RobertDyck is ** not ** in the space business ... he is in the hospitality business, which just happens to be expanding into space.

It seems to me that RobertDyck is ** far ** more interested in providing safe travel conditions and comfortable accommodations (by his standards) than he is in the details of how space craft of the size of the Large Ship are financed, constructed or operated.

Someone like the hotel operator (Bigelow)  would probably be a better bet for funding the Large Ship than a government.

A commercial focus for the enterprise seems (to me at least) to have better long term viability than depending upon the quixotic whims of governments.

(th)

Offline

#649 2021-02-01 04:38:18

RobertDyck
Moderator
From: Winnipeg, Canada
Registered: 2002-08-20
Posts: 7,811
Website

Re: Large scale colonization ship

tahanson43206, you are a fickle one. You keep coming back to this. But you keep challenging basic things. You really aren't supportive.

You don't like aerocapture. Start by reading "The Case for Mars" by Robert Zubrin. I have the first edition soft cover, published 1997. I purchased in the spring of 1998. It described "Case for Mars" conferences, the next was scheduled later that same year. I couldn't afford to go, too bad because that became the founding convention of the Mars Society. That book describes the Mars Direct mission plan. There are a few technologies necessary to make it work, several of which NASA has never accepted. One is use of In-Situ Propellant Production for return propellant. NASA developed a "design reference mission" after Mars Direct, using ISPP for the Mars Ascent Vehicle, but the return vehicle had to haul return propellant from Earth. That significantly increased cost. Another technology is centrifugal force for artificial gravity. NASA keeps designing for zero-G the whole way. The Mars Direct method of connecting the habitat with a tether to a counter weight is something NASA already tested in 1966 with Gemini 11. While Gemini 11 used a separately launched vehicle, Mars Direct would use the spent upper stage. Brilliant! But for some reason NASA is afraid of artificial gravity.

Another technology NASA is now afraid of is aerocapture. Under NASA administrator Dan Goldin, they tried to use aerocapture for Mars Climate Orbiter. The official NASA statement is they made a US measure to metric conversion error, resulting in the orbiter dipping too deeply into the atmosphere. There's now a new crater on Mars somewhere. When this happened, I noticed the NASA website listed ISS at an altitude too low. It would de-orbit soon at that altitude! When I checked the Canadian Space Agency website, it was the correct altitude. The CSA listed altitude in kilometres. When I converted from km to miles, it did not match what the NASA website said. Then I noticed "nautical miles". Turns out the NASA website listed the altitude in nautical miles, but didn't say nautical miles, it simply said "miles". Since this happened at the same time, I believe this is the "metric conversion error" that happened with Mars Climate Orbiter. Since then NASA has been ordered to do everything in metric, so the problem has been solved. But NASA now treats aerocapture as a dangerous technology. It isn't dangerous when you get units correct. Screw up units and everything will fail!

So get over it! Aerocapture is a necessary technology to reduce propellant. That reduces total vehicle mass and operation cost.

As for space for passengers: we've had this discussion many times. I've used the steam ship "SS City of New York" (1888-1923) as an example. It was a trans-Atlantic transport ship, not a luxury cruise ship. And carried a similar number of passengers. Would you kindly tell us what you would like?

Offline

#650 2021-02-01 04:56:00

RobertDyck
Moderator
From: Winnipeg, Canada
Registered: 2002-08-20
Posts: 7,811
Website

Re: Large scale colonization ship

As for business model... I've described this many times. We have an entire thread devoted to government on Mars. Part of that is the corporation that establishes a settlement on Mars will get most of it's funding from operating the Large Ship. No, Earth governments will never fund this. Mars will be independent almost immediately, so why would an Earth government want to expend billions of dollars to do it? My argument is a corporation would establish the first settlement, but that corporation will demand profit. Some people argued that they don't want a corporation. But since government won't do it, and it costs billions, who else? Read the initial post here...
Corporate Government

Above describes how the ship is operated. I have posted on this thread a few times. As for construction, I've posted on this thread as well. I could review, but tell me if you missed it. Some of the details I haven't posted. A friend wants to write a sci-fi novel. I've discussed with him many details that aren't posted here. There are some individuals who do not want to see humans settle space: not Mars, not the Moon, not anywhere. Some details to deal with those people have not been posted for obvious reasons.

Offline

Board footer

Powered by FluxBB