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#1 2018-08-12 16:03:51

SpaceNut
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Dr. Robert Zubrin Moon Direct: How to build a moonbase in four years

Dr. Robert Zubrin on March 30, 2018
http://newmars.com/2018/03/moon-direct- … our-years/

How-to-build-a-lunar-base-in-four-years.png

Reposted from Space News

The recent amazing success of the Falcon Heavy launch offers America an unprecedented opportunity to break the stagnation that has afflicted its human spaceflight program for decades. In short, the moon is now within reach.

Here’s how the mission plan could work. The Falcon Heavy can lift 60 tons to low Earth orbit (LEO). Starting from that point, a hydrogen/oxygen rocket-propelled cargo lander could deliver 12 tons of payload to the lunar surface.

We therefore proceed by sending two such landers to our planned base location. The best place for it would be at one of the poles, because there are spots at both lunar poles where sunlight is accessible all the time, as well as permanently shadowed craters nearby where water ice has accumulated. Such ice could be electrolyzed to make hydrogen-oxygen rocket propellant, to fuel both Earth-return vehicles as well as flying rocket vehicles that would provide the lunar base’s crew with exploratory access to most of the rest of the moon.

The first cargo lander carries a load of equipment, including a solar panel array, high-data-rate communications gear, a microwave power-beaming set up with a range of 100 kilometers, an electrolysis/refrigeration unit, two crew vehicles, a trailer, and a group of tele-operated robotic rovers. After landing, some of the rovers are used to set up the solar array and communications system, while others are used to scout out the landing area in detail, putting down radio beacons on the precise target locations for the landings to follow.

The second cargo lander brings out a 12-ton habitation module, loaded with food, spare spacesuits, scientific equipment, tools, and other supplies. This will serve as the astronauts’ house, laboratory, and workshop of the moon. Once it has landed, the rovers hook it up to the power supply and all systems are checked out. This done, the rovers are redeployed to do detailed photography of the base area and its surroundings. All this data is sent back to Earth, to aid mission planners and the science and engineering support teams, and ultimately forming the basis of a virtual reality program that will allow millions of members of the public to participate in the missions as well.

The base now being operational, it is time to send the first crew. A Falcon Heavy is used to deliver another cargo lander to orbit, whose payload consists of a fully fueled Lunar Excursion Vehicle (LEV). This craft consists of a two-ton cabin like that used by the Apollo-era Lunar Excursion Module mounted on a one-ton hydrogen/oxygen propulsion system filled with nine tons of propellant, capable of delivering it from the lunar surface to Earth orbit. A human-rated Falcon 9 rocket then lifts the crew in a Dragon capsule to LEO where they transfer to the LEV. Then the cargo lander takes the LEV, with the crew aboard, to the moon, while the Dragon remains behind in LEO.

After landing at the moon base, the crew completes any necessary set up operations and begins exploration. A key goal will be to travel to a permanently shadowed crater and, making use of power beamed to them from the base, use telerobots to mine water ice. Hauling this treasure back to the base in their trailer, the astronauts will feed the water into the electrolysis/refrigeration unit, which will transform it into liquid hydrogen and oxygen. These products will then be stored in the empty tanks of the cargo landers for future use — primarily as rocket propellant but also as a power supply for fuel cells and a copious source of life-support consumables.

Having spent a couple of months initiating such operations and engaging in additional forms of resource prospecting and scientific exploration, the astronauts will enter the LEV, take off and return to Earth orbit. There they will be met by a Dragon — either the one that took them to orbit in the first place or another that has just been launched to lift the crew following them — which will serve as their reentry capsule for the final leg of the journey back home.

Thus, each mission that follows will require just one $100 million Falcon Heavy launch and one $60 million Falcon 9 launch to accomplish. Once the base is well-established, there will be little reason not to extend surface stays to six months.

Assuming that cost of the mission hardware will roughly equal the cost to launch it, we should be able to create and sustain a permanently occupied lunar base at an ongoing yearly cost of less than $700 million. This is less than four percent of NASA’s current budget — or about a quarter of what is being spent yearly on the agency’s now obsolete Space Launch System program which has been going on for over a decade without producing a rocket.

The astronauts will not be limited to exploring the local region around the base. Refueled with hydrogen and oxygen, the same LEV spacecraft used to travel to the moon and back can be used to fly from the base to anywhere else on the moon, land, provide on-site housing for an exploration sortie crew, and then return them to the base. We won’t just be getting a local outpost: we’ll be getting complete global access to an entire world.

Currently, NASA has no such plan. Instead it is proposing the build a lunar orbiting space station dubbed the Deep Space Gateway. This boondoggle will cost several tens of billions of dollars, at least, and serve no useful purpose whatsoever – except perhaps to provide a launch manifest for the Space Launch System. We do not need a lunar-orbiting station to go to the moon. We do not need such a station to go to Mars. We do not need it to go to near-Earth asteroids. We do not need it to go anywhere. If we do waste our time and money building it, we won’t go anywhere.

If you want to get to the moon, you need to go to the moon. We now have it in our power to do so. Let’s seize the time.

Robert Zubrin is president of Pioneer Astronautics and the Mars Society. An updated edition of his book, “The Case for Mars: The Plan to Settle the Red Planet and Why We Must,” was recently published by the Free Press

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#2 2018-08-12 16:18:46

louis
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Re: Dr. Robert Zubrin Moon Direct: How to build a moonbase in four years

A microwave power-beaming set up with a range of 100 kilometers???  We're nowhere near that are we?


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

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#3 2018-08-12 16:46:14

SpaceNut
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Re: Dr. Robert Zubrin Moon Direct: How to build a moonbase in four years

https://spacenews.com/op-ed-moon-direct … our-years/


I believe the staging to LEO is 63 mT for the falcon heavy but what is the direct to the moon throw?

https://www.reddit.com/r/spacex/comment … con_heavy/

As brought up in that topic the throw to orbit if not reusueable is quite a bit more as we saw with the falcon 9.

So guesstimates (using 65% of GTO throw mass) are:

Falcon 9 - 3,152.5 kg to TLI

Falcon 9 Heavy - 13,780 kg to TLI

Of course the question is Could SpaceX Get People to the Moon in 2018?

The private launch company must overcome several hurdles to meet its aggressive schedule for an ambitious lunar mission and we would all be quite happy to say yes they can..

Space x did sell tickets for a lunar mission sells first tickets for moon launch

There's room aboard the Falcon 9 for another 240 pounds of additional cargo. Astrobotic Technology is selling the space for $700,000 per pound, plus a $250,000-per-payload fee for integration, communications and other support services.
But a Falcon 9 heavy would do a lot better....

But it will not happen Space X delays tourist trip around the moon

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#4 2018-08-12 18:34:50

RobertDyck
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Re: Dr. Robert Zubrin Moon Direct: How to build a moonbase in four years

According to SpaceX website as of today. Falcon Heavy to LEO 63,800kg, to GTO 26,700kg, to Mars 16,800kg.

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#5 2018-08-12 19:00:04

SpaceNut
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Re: Dr. Robert Zubrin Moon Direct: How to build a moonbase in four years

louis wrote:

A microwave power-beaming set up with a range of 100 kilometers???  We're nowhere near that are we?

LLO would be that distance but the panels are said to be on the surface. Ice is found at the bottom of craters but I think at the poles only...

Day time heating which lasts 2 weeks and would make it hard to cool the hydrogen but then again the lunar night will last 2 weeks as well to make it cold through with surface solar then you do not have power..

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#6 2018-08-12 19:07:20

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
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Re: Dr. Robert Zubrin Moon Direct: How to build a moonbase in four years

RobertDyck wrote:

According to SpaceX website as of today. Falcon Heavy to LEO 63,800kg, to GTO 26,700kg, to Mars 16,800kg.

Not sure what to think of the space x numbers for the moon but that does not mean much if the tonnage is eaten up by the payloads and not giving it any ability to land.

GW ran the retropropulsion numbers for the crewed dragon (super Draco engines) and the fuel (2 T I think) was just able to land that capsule and truck but did not have any mass yet for landing legs.
The capsule was fully loaded and would total something close to the 12 ton mark.

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#7 2018-08-12 19:24:07

SpaceNut
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Re: Dr. Robert Zubrin Moon Direct: How to build a moonbase in four years

Here are the 2 topics that are close to this topic and has the GW numbers with in them and or his website with them.

Apollo 8 redux which is the flyby mission

Apollo 11 redux go land sortie repeat

Once we have done the lifting and landing numbers we need to look at the remaining support items...

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#8 2018-08-12 21:42:13

louis
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From: UK
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Posts: 4,896

Re: Dr. Robert Zubrin Moon Direct: How to build a moonbase in four years

Back in 2015 I think the record for microwave power-beaming was around half a kilometre...I don't think we've made that much progress in the last three years to beam energy over 100 kms.  Not sure why Zubrin would be proposing this solution given the technology is not mature.

SpaceNut wrote:
louis wrote:

A microwave power-beaming set up with a range of 100 kilometers???  We're nowhere near that are we?

LLO would be that distance but the panels are said to be on the surface. Ice is found at the bottom of craters but I think at the poles only...

Day time heating which lasts 2 weeks and would make it hard to cool the hydrogen but then again the lunar night will last 2 weeks as well to make it cold through with surface solar then you do not have power..


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

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#9 2018-08-13 00:50:57

RobertDyck
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Re: Dr. Robert Zubrin Moon Direct: How to build a moonbase in four years

louis wrote:

Back in 2015 I think the record for microwave power-beaming was around half a kilometre...I don't think we've made that much progress in the last three years to beam energy over 100 kms.  Not sure why Zubrin would be proposing this solution given the technology is not mature.

Dr. Zubrin pursued his life-long dream of becoming an aerospace engineer. He landed his dream job, worked for Martin-Marietta. Then the president ordered NASA to go to Mars. NASA blew that up with 90-Day-Report. Then he got a second chance, his employer ordered all engineers to come up with a practical plan for Mars. He did. He pitched it to NASA, lobbied NASA, got some influential individuals to support it. But Congress shot it down because they still suffered sticker-shock from the 90-Day-Report. He spent his entire life since trying to push this. Like Sisyphus, eternally pushing a bolder uphill, only to have it roll down when he nears the top. So perhaps Dr Zubrin decided to take a step back, to look at aerospace engineering again. The goal of Mars was chosen by President George H. W. Bush (#41). Perhaps he needs to stop pushing that goal, and choose something that has current support. Dr. Zubrin had argued against the Moon, but that was because the 90-Day-Report cost so much that Congress of 1989 and the '90s wouldn't pay that. If current Congress will, then let's do that. Besides, one argument against the Moon was lack of water. But they found water ice. Not much, arguably not concentrated enough to harvest, but if Congress and NASA are willing to pay to pursue that, then go with it. And Dr. Zubrin argued against solar power satellites, one big argument was microwave beaming doesn't work. But if he's going to stop pushing the bolder up hill, then go with that too. Embrace everything he previously argued against. After all, one major problem with microwave beaming is moisture in air either absorbing the beam or diffusing it. Another issue is particulates in air diffusing the beam. But the Moon has no atmosphere, so perhaps (just maybe) long distance microwave beaming could work. Again, the key feature is vacuum. Maybe. Maybe.
hE2F6E4E5

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#10 2018-08-13 15:44:14

kbd512
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Re: Dr. Robert Zubrin Moon Direct: How to build a moonbase in four years

Does it strike anyone else as noteworthy that NASA has actually spent all the money requested in the 90 day report and more since that time and we still haven't gone anywhere outside of LEO?

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#11 2018-08-13 16:10:54

louis
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Re: Dr. Robert Zubrin Moon Direct: How to build a moonbase in four years

Yep, I've often thought about that.  Add up the cost of all the robot missions outside LEO, you'd definitely have enough money to get to Mars. I've said before and will say again that within one year of getting humans on Mars we will learn more about the planet than in the previous 50 years of missions.

kbd512 wrote:

Does it strike anyone else as noteworthy that NASA has actually spent all the money requested in the 90 day report and more since that time and we still haven't gone anywhere outside of LEO?


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

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#12 2018-08-13 16:50:06

louis
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Re: Dr. Robert Zubrin Moon Direct: How to build a moonbase in four years

Helpful discussion of microwave/laser power beaming...

https://space.stackexchange.com/questio … ough-space

It doesn't seem this technology is anywhere near to close to being able to transfer power reliably over 100 Kms.

Why is that solution required? You can produce plenty of power during the 14 days of continuous sunlight with PV panels on the lunar surface.

With perhaps 100 tonnes or more of supplies being delivered to the lunar surface, you don't really need to source water for your lunar mission (this is the difference from Mars, since there is no need to produce propellant on the surface).  10 tonnes of water would provide for all the needs of a 10 crew mission for a year without any water recycling - but of course, you can have water recycling, to ensure that water lasts even longer.

20 tonnes of battery storage at 250 Whs per Kg would give you about 15Kws of continuous power during the 14 days of darkness.

That could be supplemented by an emergency hydrocarbon/oxygen system.

A lightweight PV panel system that would meet the needs of a 10 person colony would probably weigh in at less than a couple of tonnes.

Here's a BFR Lunar simulation.

https://www.youtube.com/watch?v=4yC3LjKfrUM

Once you've got your base established and more supplies come in, you can then set up a robot mining mission at the poles, even if your base is hundreds of miles away - the solution is to have a continuous "conveyor belt" of automated rovers shuttling between the base and the ice mine. PV powered rovers, recharging at solar power stations along the way could easily bring in a couple of tonnes of ice per journey.

For me a lunar base will primarily have a commercial tourism role to play, coupled with science research.  There is not much need or point in attempting to set up a complex industrial infrastructure on the Moon, given how very close it is to Earth.


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

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#13 2018-08-13 18:31:57

SpaceNut
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Re: Dr. Robert Zubrin Moon Direct: How to build a moonbase in four years

BFR is not part of this discussion, lets stay focussed on inital post please and I would also add that Nasa constellation work would also not be as they were looking at a nuclear powering option.

Mission 1
Batteries on the moon swelter in the heat and then in the cold so they will need to be burried in order to keep them climate controled.
Much like the batteries the electrolysis process and liquification will need to be underground as well to climate control what happens. Its one thing to make use of heat exchanges and radiators that can be switched on and off as required to make use of the lunar cycle but its that distance between each that makes it harder for man to do.

Solar panel materials will need to be proved out that they can withstand the temperature swings.

High speed communication not truely defined enough as to type.

The telerobotic rovers and the trailers need more details of tonnage plus power capacity.

The end round up of features are about planning for a future landing.

Mission 2 & 3 should be co-missions as you want the food and supplies to be with the crew to keep it fresh for eating and not needing more water for freezed dried...

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#14 2018-08-13 19:02:04

SpaceNut
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Re: Dr. Robert Zubrin Moon Direct: How to build a moonbase in four years

Mission 2 the habitat we do not have let alone a means to land it on the moon.
Quick disconnect connect feature to power should not be much of a design issue.
The habitat science lab equipment and what we will do with it needs more information.

Mission 3 we still need to either revive the lunar lander or design a new means to get a crew to the surface and back to orbit.

Mission return home seems to have no means to return home as there is nothing in orbit and a lunar lander can not do so back to the waiting dragon inLEO.

https://www.teslarati.com/spacex-crew-d … t-gallery/

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#15 2018-08-14 04:39:17

louis
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Re: Dr. Robert Zubrin Moon Direct: How to build a moonbase in four years

I was just critiquing some of the mission assumptions:

1. Why choose an unproven and immature technology like microwave power beam transmission for such a crucial part of the mission (energy)?

2. Why is water sourcing so important when you don't need produce propellant on the Moon and you can ship it in and preserve much of it through water recycling?

3.  The moon is close by  - just 4 days away, less time than it took people to get from Europe to the USA in pre-aviation days.

I am really struggling to believe there would be any problem with operating PV panels or batteries on the moon. With reflective material and use of materials like aerogel, plus aircon plus  simple regolith cover I doubt we would have any problem with temperature insulation.   There is no atmosphere to conduct heat on Mars is there?


SpaceNut wrote:

BFR is not part of this discussion, lets stay focussed on inital post please and I would also add that Nasa constellation work would also not be as they were looking at a nuclear powering option.

Mission 1
Batteries on the moon swelter in the heat and then in the cold so they will need to be burried in order to keep them climate controled.
Much like the batteries the electrolysis process and liquification will need to be underground as well to climate control what happens. Its one thing to make use of heat exchanges and radiators that can be switched on and off as required to make use of the lunar cycle but its that distance between each that makes it harder for man to do.

Solar panel materials will need to be proved out that they can withstand the temperature swings.

High speed communication not truely defined enough as to type.

The telerobotic rovers and the trailers need more details of tonnage plus power capacity.

The end round up of features are about planning for a future landing.

Mission 2 & 3 should be co-missions as you want the food and supplies to be with the crew to keep it fresh for eating and not needing more water for freezed dried...


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

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#16 2018-08-14 21:19:22

SpaceNut
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Re: Dr. Robert Zubrin Moon Direct: How to build a moonbase in four years

Daytime on one side of the moon lasts about 13 and a half days, followed by 13 and a half nights of darkness. When the sunlight hits the moon's surface, the temperature can reach 253 degrees F (123 C). The "dark side of the moon" can have temperatures dipping to minus 243 F (minus 153 C).

https://www.forbes.com/sites/brucedormi … 4c83d57439

http://blogs.discovermagazine.com/crux/ … 3OXZDVIrGg

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#17 2018-08-15 08:17:51

louis
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From: UK
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Re: Dr. Robert Zubrin Moon Direct: How to build a moonbase in four years

Well - the Apollo landers haven't melted yet...

I don't think the temperature range is a serious impediment to setting up a base.


SpaceNut wrote:

Daytime on one side of the moon lasts about 13 and a half days, followed by 13 and a half nights of darkness. When the sunlight hits the moon's surface, the temperature can reach 253 degrees F (123 C). The "dark side of the moon" can have temperatures dipping to minus 243 F (minus 153 C).

https://www.forbes.com/sites/brucedormi … 4c83d57439

http://blogs.discovermagazine.com/crux/ … 3OXZDVIrGg


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

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#18 2018-08-15 13:22:20

GW Johnson
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Re: Dr. Robert Zubrin Moon Direct: How to build a moonbase in four years

There is no ambient temperature on the moon (or any airless world) any more than in airless space.  There are only the temperatures of objects being bathed in sunlight or shadow,  and radiating to some combination of the materials around them,  and space. 

It is rocks with a certain range of visible reflectance and infrared emissivity that reach 250-ish F in sunlight or -240-ish F in shadow on the moon. 

The spectral reflectivity and emissivity of aluminum is different from rocks,  which is why the Apollo landers did not get that all hot or cold on the moon,  and so were not weakened by over-hot material temperatures in the portions exposed to sunlight,  or excessive cold brittleness in the shaded portions. 

Very special attention must be paid to spectral characteristics of surface materials and coatings,  in order to achieve this result.  It is not a trivial design issue.

These thermal equilibria usually obtain within a few hours at most.  The day/night length on the moon is quite long in comparison.  Solar panels must accommodate the same thermal equilibria,  but you are without generating capability for 13+ days worth of continuous night,  meaning you need either gigantic batteries,  some sort of fuel-based power,  or else atomic power. 

THAT is why the Apollo landing zones were all situated in daylight only. That is also what the Kilopower nuclear Stirling generator developments are all about.

Mars does indeed have an atmosphere so that there really is an ambient temperature.  But it is a very thin one,  first cousin to the vacuum of space at 0.007 times Earth sea level density.  Heat transfer coefficients for convection scale roughly as density raised to the 0.8 power.  So,  conduction and radiation heat transfer dominate the Martian picture far more than convection,  unlike here on Earth.  But,  it's not zero convection,  either,  the way it is in space or on the moon.

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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#19 2018-08-15 19:34:54

SpaceNut
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Re: Dr. Robert Zubrin Moon Direct: How to build a moonbase in four years

This seems to have also been over looked in that Space Radiation Devastated the Lives of Apollo Astronauts. 07/28/16 New research points to serious concerns about human survival during deep space travel.

The study compared the mortality rates of lunar astronauts who have passed away to astronauts who never flew and to those who have only made it to orbit.

The number of cardiovascular disease-related deaths among the deep space astronauts were significantly higher.

The rate among  astronauts who never flew is 9%. Among low-Earth orbiting astronauts, its 11%. For the men who travelled to the Moon, a staggering 43%, or 4-5 times higher than their less-travelled colleagues.The one exception to the study was Apollo 14 astronaut Edgar Mitchell, who passed away after the study’s data had already been collected.

Researchers also exposed mice to a similar type of radiation and after six months, the mice demonstrated sustained cellular breakdown and impairment of the arteries—which, in the human body, leads to cardiovascular disease. “What the mouse data show is that deep space radiation is harmful to vascular health,” said Delp.

These revelations pose tough questions for NASA and the firms from the agency’s NextSTEP program that are bidding to build a habitat that can protect humans during long-duration spaceflight.

I recall seeing images ofan astronauts foot and the big toe that had seen a bit of what appeared to be frostbite from the outing on the moon but could not seem to find them...

http://www.spiegel.de/international/wor … 37327.html

https://www.satra.com/bulletin/article.php?id=1746]The first steps on Mars?

Exploring the requirements for boots that may be worn on future missions to one of our closest neighbours.

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#20 2018-08-15 20:25:58

Void
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Re: Dr. Robert Zubrin Moon Direct: How to build a moonbase in four years

I would ask that we be considering other factors in such a measurement.  Sure radiation is almost completely bad, except for the spectrum that works for us.

However, these Men were selected to be of a certain type.  The candle which burns brightest, might burn out sooner.

Not sure that that is part of the answer, radiation damage is bad, but this other aspect perhaps should be considered.

https://www.youtube.com/watch?v=wRxHYHPzs7s

https://www.goodreads.com/quotes/90347- … ns-half-as

But we must consider magnetic and mass methods of blocking radiation.

Also genetic engineering.
https://www.indiatimes.com/technology/s … 76002.html

Done and fun.

Last edited by Void (2018-08-15 20:32:27)


I like people who criticize angels dancing on a pinhead.  I also like it when angels dance on my pinhead.

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#21 2018-08-15 20:37:47

GW Johnson
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Re: Dr. Robert Zubrin Moon Direct: How to build a moonbase in four years

GCR varies more-or-less sinusoidally from a min of 24 REM in a year to a max of 60 REM in a year,  on a roughly 11 year period (matching the solar activity cycle).  Max GCR occurs during solar activity minimum.  For comparison,  the max limit for astronauts is 50 REM in a year,  25 REM max in any one month,  and a career limit that varies with age and gender,  but maxes out at 400 REM in a lifetime. Those limits are roughly twice the limits for an Earthly nuclear worker. 

The astronaut exposure limits were calculated for an estimated cancer risk increase of 3% over civilians.  Maybe that calculation is no good,  and maybe it really is good.  You can find articles and papers that say pretty much anything.   I got the quoted numbers off the NASA radiation website.  They list lots of references,  not just a few.  So I tend to think they are fairly reliable. 

However,  the link between radiation and circulatory disease is a surprise.  I had not heard that before. 

It is the GCR (and to a small extent the exposure crossing the Van Allen belts) that the lunar astronauts were exposed to.  I do not know if they saw 24 vs 60 REM/year rates.  What they were NOT exposed to was a solar flare event.  If such had occurred,  they would have died in a matter of hours.  Such can range from 100's to 10,000's of REM per HOUR.  The nominal figure of merit for a fatal dose is 50-to-100 REM in a "short time" (minutes to hours).

The GCR is the really high-energy radiation type,  but it is a very slow drizzle.  Solar flare radiation is far lower energy and less penetrating,  but there is typically a truly enormous flood of it during any given event. 

According to the NASA radiation site,  the same 15-20 cm of water that makes a big flare survivable also cuts the GCR by a significant fraction (from 60 REM/yr down to nearer 50 REM/year).  Thicknesses vary for water vs aluminum vs hydrogen,  but all three are in the same general thickness class:  near 15-20 cm. A spacecraft hull at 0.05 to 0.10 inch thick aluminum might as well not be there at all,  radiationally speaking. 

GW

Last edited by GW Johnson (2018-08-15 20:45:39)


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 2018-08-16 03:13:20

louis
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From: UK
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Posts: 4,896

Re: Dr. Robert Zubrin Moon Direct: How to build a moonbase in four years

I think if you read Tom Wolfe's wonderful book "The Right Stuff" you can see that the astronauts who got chosen for the toughest missions were amongst the most hard-living, hard-drinking, most driven types...

Void wrote:

I would ask that we be considering other factors in such a measurement.  Sure radiation is almost completely bad, except for the spectrum that works for us.

However, these Men were selected to be of a certain type.  The candle which burns brightest, might burn out sooner.

Not sure that that is part of the answer, radiation damage is bad, but this other aspect perhaps should be considered.

https://www.youtube.com/watch?v=wRxHYHPzs7s

https://www.goodreads.com/quotes/90347- … ns-half-as

But we must consider magnetic and mass methods of blocking radiation.

Also genetic engineering.
https://www.indiatimes.com/technology/s … 76002.html

Done and fun.

Last edited by louis (2018-08-16 14:17:12)


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

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#23 2018-08-16 03:22:20

louis
Member
From: UK
Registered: 2008-03-24
Posts: 4,896

Re: Dr. Robert Zubrin Moon Direct: How to build a moonbase in four years

Wasn't the lunar module little better than a tin can? I would hope we could seriously improve on radiation protection offered on Apollo Missions. Another area to look at is lunar dust inhalation...wasn't that a serious issue ie dust contamination within the module.


SpaceNut wrote:

This seems to have also been over looked in that Space Radiation Devastated the Lives of Apollo Astronauts. 07/28/16 New research points to serious concerns about human survival during deep space travel.

The study compared the mortality rates of lunar astronauts who have passed away to astronauts who never flew and to those who have only made it to orbit.

The number of cardiovascular disease-related deaths among the deep space astronauts were significantly higher.

The rate among  astronauts who never flew is 9%. Among low-Earth orbiting astronauts, its 11%. For the men who travelled to the Moon, a staggering 43%, or 4-5 times higher than their less-travelled colleagues.The one exception to the study was Apollo 14 astronaut Edgar Mitchell, who passed away after the study’s data had already been collected.

Researchers also exposed mice to a similar type of radiation and after six months, the mice demonstrated sustained cellular breakdown and impairment of the arteries—which, in the human body, leads to cardiovascular disease. “What the mouse data show is that deep space radiation is harmful to vascular health,” said Delp.

These revelations pose tough questions for NASA and the firms from the agency’s NextSTEP program that are bidding to build a habitat that can protect humans during long-duration spaceflight.

I recall seeing images ofan astronauts foot and the big toe that had seen a bit of what appeared to be frostbite from the outing on the moon but could not seem to find them...

http://www.spiegel.de/international/wor … 37327.html

https://www.satra.com/bulletin/article.php?id=1746]The first steps on Mars?

Exploring the requirements for boots that may be worn on future missions to one of our closest neighbours.


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

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#24 2018-08-16 10:39:44

GW Johnson
Member
From: McGregor, Texas USA
Registered: 2011-12-04
Posts: 3,643
Website

Re: Dr. Robert Zubrin Moon Direct: How to build a moonbase in four years

I think the astronaut pressure cabin on the Apollo LM was something like 0.020 inch think aluminum sheet.  Parts of it were covered with a blanket that had an aluminum foil outer layer for reflectance,  plus some insulation. 

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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#25 2018-08-16 12:19:05

Oldfart1939
Member
Registered: 2016-11-26
Posts: 1,714

Re: Dr. Robert Zubrin Moon Direct: How to build a moonbase in four years

The LEM would be envious of a well-constructed tin can.

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