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#1 2019-09-03 05:07:42

RobertDyck
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From: Winnipeg, Canada
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Large scale colonization ship

I mentioned this elsewhere, but we need a dedicated topic. This is ship intended to carry a large number of passengers. Intended to travel from Earth orbit to Mars orbit and back. Aerocapture at both planets. Heat shield made of Nextel 440 fabric, which is the fabric that NASA's Ames Research Center selected for advanced thermal blankets called DurAFRSI. That's a synthetic ceramic fabric. Carbon fibre can withstand more heat, but carbon fibre is not as durable so not as reusable. Rotation for artificial gravity; a wheel behind a giant fabric umbrella heat shield.

SpaceX Starship to ferry passengers from Earth to the interplanetary ship. And Starship fuel tanker to refuel it as well. On Mars, a Starship to act as Mars shuttle.

Updated math with more precision. Mars acceleration for the ship, so 38.0% that of Earth gravity. Radius 37.76 metres from centre of rotation to surface of the floor, 3 RPM. One deck. Circumference 237.25 metres. Ring width 19 metres. This allows 2 isles for cabins, corridors 1.5 metres wide, outside cabins have a window, inside cabins do not. Standard cabin size 4x2.4 metres.

This is a single cabin from Norwegian Epic cruise ship. Queen size bed.
642e2b88a4c668f.jpg

This shows a 5-person cabin, but the bed on the right could be bunk as well for 6-person. With UK small single beds: 30"x75" (75cm x 190cm). The table and stool on the right would be replaced by a washroom: shower stall, toilet and small sink. A pair of single beds could be replaced with a queen size bed, allowing parents to sleep together and children each their own bed. Military ships have the mattress lift to access storage under the bed, but they have 3 bunks high. With two bunks you can have drawers like a "Captain's bed".
89721678e83b091a087fff8e33795338.jpg

Premium cabin would be twice as long and twice as wide for 4 times floor area.

A ship this size could have 162 "economy" cabins with average 5 persons each, 90 "single" cabins with two persons each, 4 premium cabins with 2 persons each, and 1 luxury suite that's 4 times the size of premium. That would carry 1,000 passengers and crew.

That leaves 66.85 metres of circumference for food storage, life support, and facilities such as kitchen or dining room. That's 28.177% of floor area. Centre of rotation would have a zero-G hub with padded walls where passengers could enjoy themselves. Docking port at the zero-G hub. A portion of the fabric heat shield over the hub would move out of the way to during flight to provide a view of where they're going. A parasol would move in place for aerocapture. Aft of zero-G hub would be zero-G storage. Aft of that propellant tank and engines.

Beds would require a back-rest so passengers don't slide off the end of the bed. During acceleration thrust would be toward the window for cabins on one side of the isle, toward the door for the other. During aerocapture thrust would be reverse. Ring rotation would never stop.

::Edit:: Centrifugal force calculator

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#2 2019-09-03 05:11:47

RobertDyck
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Re: Large scale colonization ship

All cabins would have a large flat screen TV that could be set to one of the high-def video cameras on the ship: forward from hub, forward from ring, aft from ring, aft from engines, etc.

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#3 2019-09-03 07:40:26

tahanson43206
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Re: Large scale colonization ship

For RobertDyck ... Thanks for this interesting new topic, and for the substantial launch.

I did a  quick search of the forum archives looking for "aldrin" and "cycler" and found that a long series of posts contain those words, including one by RobertDyck, posted on 2018-04-27, where you quoted from Wikipedia on the subject. 

FluxBB confirms this is the only post with these words and RobertDyck as author.

Your new topic could be stretched (I think) to include an Aldrin Cycler, which would not have the acceleration/deceleration costs of a "traditional" ship such as you've opened this topic to "launch"

There is quite a bit of science fiction written with an Aldrin Cycler as the background theme.

Dr. Aldrin is still alive, and potentially available for consultation, but I gather (from a long list of Google citations) that he's been dealing with some challenges in recent years.

I ran a quick search for "technical literature on aldrin cycler", and Google returned a promising list of citations.

This paper from 2005 includes Dr. Aldrin in the list of contributors:
https://pdfs.semanticscholar.org/b54e/7 … b19d1d.pdf

Here and now is as good a place as any for you (or someone) to decide to assemble a team to put a first version of this concept into service.

This topic is a great start.

Edit: I note that the original presentation (from 1985) featured two cyclers, one optimized for a fast transit to Mars, and one for a fast return.

(th)

Last edited by tahanson43206 (2019-09-03 07:42:22)

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#4 2019-09-03 10:30:22

RobertDyck
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Re: Large scale colonization ship

Sigh. No. This is not an Aldrin cycler. Aldrin wanted a very large vehicle in a perpetual solar orbit. That's different. That requires a vehicle to catch-up when it leaves Earth, and to depart the cycler to catch up to Mars. This actually enters Mars orbit, then returns to Earth and enters Earth orbit.

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#5 2019-09-03 11:05:25

tahanson43206
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Re: Large scale colonization ship

For RobertDyck re #4 ....

Thank you for the added detail about ferries needed at Earth and Mars.

It is possible the trades have already been done, so that the costs of one solution versus the other may be known.

I would expect the trades to show that the cycler is both more cost effective as well as faster, but am prepared to be surprised.

Certainly the cycler can be incrementally improved with more and better amenities as times goes on, although I would expect even the first version to have Earth normal gravity for passengers and crew, and near Earth sea level radiation protection.

Freight would (presumably) travel on the long legs.

There may be distinct advantages to the space liner concept you've outlined, so that it would succeed in the market place.

I can imagine flexible scheduling as a distinct advantage, when sufficient energy becomes available to allow it as an option.

(th)

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#6 2019-09-03 13:27:42

RobertDyck
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Re: Large scale colonization ship

What I called an economy cabin is the same as third class on trans-Atlantic ships of the 1900s and 1910s. But those ships had a toilet against the end wall between bunks, so you're in the middle of the room. I include an RV size washroom.

For the lower end bunks, one bunk could be slid over to join the 2 bunks as one queen size bed. The bunk would slide on rails like modern car seats. The bunk would have to be locked in place for acceleration and aerobraking. And you don't want the bed opening while sleeping.

Premium cabins would have a couch. That could be a hide-a-bed. And a hide-a-bed in the Luxury suite. For flexibility.

::Edit:: I said the ship could carry 1,000 passengers and crew. If the captain takes one "single" cabin with no roommate, that reduces total complement by one. If each Premium cabin and Luxury suite has 2 people per hide-a-bed, that adds 2 per cabin. And I said average of 5 people per economy cabin, but maximum is 6. That makes maximum 1,171 people.

Last edited by RobertDyck (2019-09-05 14:53:02)

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#7 2019-09-03 17:27:22

SpaceNut
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Re: Large scale colonization ship

We have known for sometime here on Newmars that the ship the gets you to orbits will not be the  best ship for transit from one place to another long ago. The issue is we are not manufacturing anything in space as of yet to build from just doing science. So without a space port shipyard to build things in we will be stuck in the getting bigger and bigger mode.

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#8 2019-09-03 17:48:34

RobertDyck
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Re: Large scale colonization ship

I still argue we can use ISS as the construction shack to build the ship I just described. And use the station arm for construction. One reason to return to Earth orbit with each trip is so we can maintain/service/upgrade/repair the ship at ISS. Yes, use ISS as the ship yard.

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#9 2019-09-04 02:32:47

Terraformer
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Re: Large scale colonization ship

The ISS is not in the best of orbits to be servicing interplanetary vessels. A dedicated station would be far better, and if we're launching enough mass to be building such craft, we can afford to do it properly.

As GW has said before, part of what we'd need would be a large (unpressurised) enclosed volume that's lit evenly and shielded from the sun. That's not going to be heavy, certainly not in comparison to Starship 2.0.


"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

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#10 2019-09-04 09:18:52

tahanson43206
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Re: Large scale colonization ship

For Terraformer re #9 ...

Your observation here is intriguing.  Can you suggest a better orbit than the ISS for an Interplanetary Service Station?

I've seen an argument or two in favor of Lunar L1, because of its energy benefits, and the proximity of ample supplies of material.

However, I've only seen a tiny part of the total volume of knowledge assembled on this topic, and would be interested to see more.

(th)

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#11 2019-09-04 11:48:45

Terraformer
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Re: Large scale colonization ship

L1 is good for using gravitational assists and the Oberth effect, and a must if your spacecraft use low-thrust propulsion, otherwise you'll spend weeks escaping Earth orbit.

Other than that, an equatorial orbit.


"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

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#12 2019-09-04 12:10:08

tahanson43206
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Re: Large scale colonization ship

For Terraformer re #11 ...

Thanks for your reply, with endorsement of L1 for some interplanetary missions, and with the suggestion of Equatorial LEO for others.

There appears to be one specific location well positioned to take advantage of a decision to build a service station in Equatorial LEO ....

https://en.wikipedia.org/wiki/Guiana_Space_Centre

Flights returning from outside the Earth-Moon system would (presumably) have a number of options for navigation planning, in decades ahead.

The ISS will (presumably) remain in service for some time.

The Chinese will surely build a permanent version of their station, in an orbit that satisfies their requirements.

The French and European Union can (if they so choose) build a station at Equatorial LEO.

I note that India is well positioned to participate in an equatorial LEO project.  They do not have land directly on the Equator, but they are closer than other currently space faring nations (other than France/EU). 

I am hoping someone in the forum membership would be able to add to this discussion, for the enlightenment of future space navigators and captains, and for the guidance of future entrepreneurs interested in serving whatever markets develop in decades ahead.

(th)

Last edited by tahanson43206 (2019-09-04 12:13:18)

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#13 2019-09-04 13:03:12

RobertDyck
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Re: Large scale colonization ship

Lower inclination means less propellant required to reach it from Earth. In 1968 NASA wanted to put a station at 50° inclination for Earth observations. That passes over the vast majority of cities, including Russia. But inclination can't be lower than the latitude of your launch site, or rockets can't reach it. You could launch into a higher inclination orbit then transfer to low, but any on-orbit change of inclination takes a hell of a lot of propellant. ISS was put at 51.6° because that's the exact latitude of the Proton launch pad at Baikonur. It was only 1.6° higher than NASA wanted anyway.

Some have argued to launch a new station accessible only from KSC, not Baikonur. That means drop inclination to 28°.

Altitude is also interesting. You have to stay in LEO because medium Earth Orbit would be in the Van Allen belts. You don't want to put a station with people in concentrated radiation belts. Lower altitude is easier to reach but lower altitude has more residual atmosphere requiring reboots more often. ISS is at 400km altitude +/-10 km. Hubble was 600km. ISS has thrusters on the Russian side to keep it orbit. Hubble doesn't but Hubble is so high it'll take about 87 years to fall out of orbit. Shuttle was barely able to reach that altitude, and that altitude reduced how much weight it could lift.

::Edit::
Summary: US military contractors such as Boeing and Lockheed-Martin have gouged NASA for decades. So you want the station to be accessible from the Russian launch site for competition. You don't what the station too high because that reduces lift mass of launch vehicles, but you don't want it too low because that makes the orbit unstable.
Bottom line: it should be exactly where it is.

Last edited by RobertDyck (2019-09-04 16:18:26)

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#14 2019-09-04 17:05:57

SpaceNut
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Re: Large scale colonization ship

L1 or L2 are poor as to get materials from the proximity of the moon means wasting fuel to land and then fuel once more to get back tothe station.
The moon is the better shipyard location for that reason when given that choice.
The ISS is only slightly better in that material goes up but its a free ride back down for the most part unless you are planning on recovery of a BFR as that would require landing fuel in order for it to transport more for a lower cost.
BFR in its current state of requiring refueling on orbit makes it a poor ship for planetary transport but thats due to design of maximum lift and not destination.

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#15 2019-09-04 18:14:10

tahanson43206
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Re: Large scale colonization ship

For SpaceNut re #14 ...

Thanks for the reminder about the costs of traditional rocket powered movement of materials from the Moon.

A number of years ago, Gerard O'Neill and others proposed launching material from the Moon using magnetic launchers.  The O'Neill team built prototypes on Earth to demonstrate the operating principles, and I can confirm watching one such demonstration at Princeton.

Since then (ca 1985) I am confident the engineering knowledge that would be required to build and deploy such a system has probably advanced significantly, but I've lost touch with progress of the field.

The launcher was to have been powered by Solar energy, and the packets of material were to be collected by large baskets due to drift over the large distances involved.

My expectation is that when people land on the Moon to stay, the magnetic launcher ideas will be dusted off in short order, because they are so much more efficient than (as you pointed out) traditional chemical rocket propulsion.

(th)

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#16 2019-09-04 19:33:26

SpaceNut
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Re: Large scale colonization ship

The projectile mass equation of acceleration means we are going to have a problem with slowing it done to capture the precious cargo. Which means fuel to slow it down.

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#17 2019-09-05 07:16:53

RobertDyck
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Re: Large scale colonization ship

This discussion is about a practical ship for large scale colonization. Not somebody's wet dream. We aren't going to build another space station. Not at Earth-Moon L1, not Earth-Moon L2, not anywhere else.

Remember history, why we're here. On July 20, 1989, President George H. W. Bush stood on the steps of the Air and Space museum and gave the order to go to Mars. NASA came back 90 days later with the 90 Day Report, which asked for everything under the Sun. It had a price tag of $450 billion in 1989 dollars. Congress took one look at the price tag and said "No way in hell!" Unfortunately some people in NASA still think they're executing that plan. Look at what they've done. They built Orion, a capsule far to big, heavy, and expensive for a mission to Mars. They built ISS, instead of US space station Freedom. They're currently building SLS. Although Mars Direct did include the Ares launch vehicle, that's SLS block 2. NASA is currently working on SLS block 1 and 1B, no progress on block 2. NASA claims they need not only a mission to the Moon, but a permanent base on the Moon. The 90 Day Report also called for a second space station to act as a shipyard to construct the Mars ship. You now calling for that is offensive! No, we don't need it!

Apollo was able to rendezvous the LM with CSM in lunar orbit without any sort of space station. That was in the 1960s, we certainly don't need a lunar space station now. And we don't need a shipyard to build a Mars ship. We built ISS without a shipyard, we can build a Mars ship just as well.

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#18 2019-09-05 07:35:12

tahanson43206
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Posts: 2,183

Re: Large scale colonization ship

For RobertDyck re #1 ...

Updated math with more precision. Mars acceleration for the ship, so 38.0% that of Earth gravity.

Just to confirm for those who will be reading this topic in the future ...

1) How long will the thrust at 38% G run on the Earth to Mars start
2) How long will the thrust at 38% G run at the Mars rendezvous
3) What technology will be used to create that thrust

Thanks for keeping the topic on track.

Best wishes for attracting the kinds of talent and skill sets you'll need for a design team.

The mission you've described seems (to me at least) worthy of support.

Competition of ideas is the key to the entertainment value of a forum like this, and it is even remotely possible a few readers may learn something.

However, the payoff for the topic manager is to attract the people who are willing to help push.

At some point the project will compete for funding on a large scale.

(th)

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#19 2019-09-05 07:39:04

GW Johnson
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Re: Large scale colonization ship

I am unsure of the advantage of a cycler,  given that the same delta-vees are required to get on and off the cycler as to just fly to the destination in the first place. 

Can anyone explain?

GW


GW Johnson
McGregor,  Texas

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

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#20 2019-09-05 07:45:10

tahanson43206
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Registered: 2018-04-27
Posts: 2,183

Re: Large scale colonization ship

For GW Johnson re #19

I've opened a new topic for discussion of cyclers. 

RobertDyck has requested that discussion in this topic support the title.

If you are willing, I'm wondering if you can assist him with planning his navigation?

That's assuming he would welcome your assistance.

I'd like to see this new topic develop into an action plan suitable for funding.

(th)

Last edited by tahanson43206 (2019-09-05 07:45:33)

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#21 2019-09-05 11:32:32

GW Johnson
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Re: Large scale colonization ship

Your "large scale colonization ship" has basically 3 fundamental characteristics:  (1) enough interior space to hold a very large number of people in relative comfort,  (2) protection of those people from space radiation,  particularly solar flare events,  and (3) large enough to spin for artificial gravity so that the passengers arrive fully healthy.

One possible candidate for this has been known feasible since the late 1950's into the early 1960's.  We have never had an application requiring it before,  which is why it has been forgotten to death since then.  THIS colonization ship thing IS the application. 

That candidate is nuclear explosion propulsion,  the old Project Orion idea pursued at General Atomics in San Diego for the USAF in that mid-50's to 1965 time frame.  The nuclear devices need an update from 1950's technology,  but bear in mind these are nuclear shaped charges.  They make poor bombs,  but are excellent as propulsion items.  You change the neutron reflector geometry to achieve a spindle-shaped radiant blast,  not a spherical one.

The side effects anticipated then were nuclear fallout from each ship launched from Earth.  That fallout total is equal to a single megaton-range warhead tested in the atmosphere,  which is tolerable if we only launch a few of these things.  The really serious side effect was not identified "for sure" until the Starfish Prime shot in 1962,  which was 4 megatons burst 200 miles into space.  That side effect is EMP.  You'll have to launch these things from a very isolated location,  with isolation of things on the surface beneath its flight path,  and that path NOT into low Earth orbit!

NASA looked at this circa 1965 as an alternative to NERVA for going to Mars.  At only 5000 tons of vehicle,  it was no better than the NERVA they were already funding through AEC.  Explosion propulsion is unique in that it works better and better as the ship gets larger and larger.  You are looking at 10,000-20,000 sec Isp at vehicle masses 10,000 to 20,000 tons,  and at very high thrust to weight,  most unlike electric propulsion.  In point of fact,  it is difficult to design these things accelerating at less than 2-4 gee. 

These things are welded together of 2-inch steel plate,  and are about the same size as a destroyer or a cruiser.  The crew on a warship that size is a couple of thousand (plenty of room for lots of people!).  That's about 39-40 g/sq.cm radiation shielding just in the steel plate hull by itself.  You only need about 15-20 g/sq.cm to shield effectively against solar flare events. 

At warship density,  if the form factor is about 4:1 L:D,  the diameter of a 20,000 ton item exceeds about 200 feet.  That's a 30 m spin radius,  spinning like a rifle bullet.  At 4 rpm (tolerable by anyone),  that's near 0.3 gee at the outer hull.  Build it short and squat,  and get more gee,  varying as D squared.  56 m spin radius is 1 full gee at 4 rpm.  Think "FAT BOY"!

The biggest limitation on using this thing is EMP.  You cannot operate routinely out of LEO (or LMO for that matter).  Anything underneath it that is electronic WILL be fried. Must use a higher orbit to dilute the EMP.  Mars is not limited by radiation belts the way Earth is (the Van Allen belts start getting severe about 900 miles up,  except for the South Atlantic Anomaly).

GW

Last edited by GW Johnson (2019-09-05 11:44:03)


GW Johnson
McGregor,  Texas

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

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#22 2019-09-05 13:41:48

RobertDyck
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Re: Large scale colonization ship

Ohhh! Nuclear pulse propulsion, aka Project Orion. Not to be confused with the modern space capsule called Orion. That means deliberately set off a nuclear bomb, and your craft has to be inside the blast radius for it to work. Neutron radiation with each burst is significant. There is no neutron radiation in space, the only neutron radiation in a spacecraft is secondary radiation. This would deliberately give all passengers a hell of a lot of it.

The Outer Space Treaty bans weapons of mass destruction from Earth orbit, installing them on the Moon or any other celestial body, or otherwise stationing them in outer space. This prohibits the nuclear devices that are the source nuclear pulses for propulsion. Nations would fear this is a covert way to place nuclear bombs in Earth orbit so they can be quickly dropped on enemy targets. This is a bad idea.

You mentioned Nuclear thermal rockets, eg NERVA. That's a good idea. I have pointed out Timberwind developed by the US Air Force in 1990 has dramatically lower reactor mass. The critical problem with NERVA was reactor mass, resulting in engine mass. NERVA was updated in 1990, no physical prototype built, computer analysis and simulation only. Timberwind was also developed in 1990. We should take ideas from Timberwind to reduce reactor mass. Timberwind had the problem of agglomeration; as it operated some of the pebbles would melt together forming a solid mass. That made Timberwind single-use only, it could not be restarted.

They developed NERVA until in 1974 it was ready for testing in space. Designed for a new Saturn IVB stage, it would replace the J-2 engine of the third stage of a Saturn V. The stage would not have the bulkhead separating LOX from LH2 because NERVA required pure LH2. Designs from 1968 showed a longer stage to increase propellant volume, but same stage diameter. Saturn V used its third stage for 2 purposes: Earth orbit circularization, and TLI (aka Earth orbit departure). This required the stage to be restartable, it required one engine start for each burn. But NERVA was designed to be started only for Earth orbit departure. That meant something else would have to circularize orbit. A modification of Saturn V was developed for Mars, with F-1A engines that produce 1.8 million pounds thrust instead of the standard F-1 engines that produced 1.5 million pounds for Apollo 4-14, and upgraded F-1 engines that produced 1.522 pounds thrust for Apollo 15-17. Presumably the Saturn V for Mars would be 4 stage, with a standard third stage, and the NERVA stage stacked on top. Would the 3rd stage have a shorter propellant tank since it would be used for circularization only? And the NERVA stage a longer tank?

NERVA 1990 version:
Thrust(vac): 34,000 kgf. Thrust(vac): 333.40 kN. Isp: 925 sec. Mass Engine: 8,500 kg.

Timberwind 45:
Thrust(vac): 45,000 kgf. Thrust(vac): 441.30 kN. Isp: 1,000 sec. Isp (sea level): 890 sec. Burn time: 449 sec. Mass Engine: 1,500 kg.

Note: Timberwind had higher thrust and dramatically lower engine mass. One issue is NERVA was designed to produce electric power when not used for propulsion, Timberwind was propulsion only. NERVA embedded nuclear material in ceramic fuel elements, so if a launch failure occurred the nuclear material would remain embedded. It wasn't encased, it was embedded, think of raisins in raisin bread. If an element split open it would expose a new face, but the nuclear material would not spill out.  Timberwind used pebbles of pure uranium metal. Not turning on the reactor until Earth orbit departure meant if a launch failure occurred, the nuclear fuel elements would fall out of the sky never having active fission. Uranium is so safe you can handle it with nothing more than the loose plastic gloves you get with oven cleaner. Once the reactor turns on, each uranium atom is split in two, the two fragments are known as fission fragments. Those fission fragments are so radioactive that you want several feet of concrete or 10 feet of water between the fuel element and you. If a rocket with NERVA fails, all you need is people with those cheap plastic gloves picking up nuclear fuel elements, put them in mason jars and top-up with water. We need something that simple.

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#23 2019-09-05 14:04:07

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

Mini-Magnetosphere is a radiation shield. It duplicates Earth's magnetic field. For Earth, charged plasma from solar wind gets trapped in the magnetic field, which orbits the Earth. Anything with charge moving in a circle creates a magnetic field, so this increases Earth's magnetic field. That traps more plasma, which orbits, which creates more magnetic field, etc. The maximum size depends on strength of the magnetic field you start with. Study by the University of Washington estimated the device would be only 50kg. Would it have to be larger to protect a ship this big?

NASA study from 2005: Revolutionary Concepts of Radiation Shielding for Human Exploration of Space
Includes researchers from University of Washington, Seattle, and The University of Alabama in Huntsville.

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#24 2019-09-05 14:14:48

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

GW Johnson,

You say 4 RPM is tolerable. I tried to calculate for 2 RPM, but felt the result was too large. The compromise I came up with is 38.0% gravity, 3 RPM, 37.76 metre radius from centre of rotation to surface of the floor. You recommend 100% gravity with 4 RPM and 56 metre radius. Ok, how big is that? I calculated with only one deck at 37.76 m radius we can accommodate 1,000 people. Common spaces are quite limited, definitely not as much recreational space as a cruise ship. But increasing to 56 metre diameter? How big is that? With a ship that size, can we use aerocapture to enter planetary orbit at both Mars and Earth?

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#25 2019-09-05 16:54:40

Oldfart1939
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Registered: 2016-11-26
Posts: 1,805

Re: Large scale colonization ship

Rob-I've been a supporter of Nuclear Thermal for a long time. The Isp is very attractive for deep space missions as a boost stage leaving Earth orbit. Then it could become a throwaway with it's ultimate demise on the Sun afterwards, neatly dealing with the Nuclear waste issues. It could be the big boost and then trajectory corrections made by chemical propulsion and cold gas thrusters on the manned or unmanned spacecraft carrying payload. Treat the booster as a disposable solid rocket?

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