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#1476 2021-09-26 15:22:35

GW Johnson
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From: McGregor, Texas USA
Registered: 2011-12-04
Posts: 4,858
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Re: Starship is Go...

The infrastructure is mostly (but not entirely) in-place at Boca Chica for Starship/Superheavy launches.  It is not yet in place at Canaveral,  nor is it in place on Musk's offshore rigs.  Nor does SpaceX yet fully understand exactly what that infrastructure is going to be.  They will fly missions out of Boca Chica to figure all that infrastructure out,  as well as refine what Starship and Superheavy are going to be. 

Once they understand what the infrastructure is really going to be,  you will see it built on the offshore platforms,  and at Canaveral.  It will be far easier to get a more "generous" permit to fly off the platforms and at Canaveral.  Once one of those is ready,  that is when you will see the flight rate go up. 

The flight rate from Boca Chica itself will never be very high.  Too many people live too close,  and too many public roads and facilities have to be closed for every test.  THAT is why the permit is so hard to get.  It would be well not to forget that.

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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#1477 2021-09-28 14:49:25

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

Re: Starship is Go...


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

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#1478 2021-10-02 12:48:44

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

Re: Starship is Go...

Testing has resumed...the nose cone tiles are an issue.

Mechazilla arms in operation later this month, possibly.

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


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

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#1479 2021-10-02 14:18:33

GW Johnson
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From: McGregor, Texas USA
Registered: 2011-12-04
Posts: 4,858
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Re: Starship is Go...

They need to test the methane tank too.  Methane is a more-demanding cryogen than oxygen. 

Assuming no show-stoppers emerge from the public comment interval,  it would appear that the permit delay might be ending.  We will see if the final two tanks and the last of the arm hardware get installed before the permit is issued. 

Once the hardware AND the permit are in place,  then and ONLY THEN will we see an attempted orbital flight with Starship/Superheavy. 

Solving the tile-shedding problem is NOT a prerequisite for this first flight.  Both the booster and the "Starship" are supposed to land in the ocean on this first flight,  if they even make it that far.  We have yet to see a published flight plan where either is actually recovered,  except as debris floating in the ocean. 

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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#1480 2021-10-02 18:58:14

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
Posts: 25,943

Re: Starship is Go...

I believe the nose of the shuttle was a one piece for that reason....

Its mostly a fueled up staging test for the first stage shutting down and then separation firing of the second stage in the star ship.

One proposed purpose in the "Next up for the coast to coast" launch for real flights is the actual landing being stuck even if the first stage is not recovered. Of course the starship needs the ability to do a return flight other wise is just junk at that point.

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#1481 2021-10-03 10:52:52

GW Johnson
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From: McGregor, Texas USA
Registered: 2011-12-04
Posts: 4,858
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Re: Starship is Go...

Hi Spacenut:

The Shuttle's heat shield was not all ceramic tiles,  and the design of it was changed somewhat over the life of the vehicle.  The leading edges and nosetip were made of carbon-carbon composite,  which is a very slowly-ablating ablative material,  at orbital entry conditions.  Every few to several flights,  these pieces were replaced. 

The windward belly and wing-bottom surfaces were covered in ceramic tiles deliberately made black to enhance their emissivity,  which also makes them more expensive than white tiles.  This was needed because windward-side heating rates at 20-40 degree AOA ate high,  although less than leading edge and nosetip heating.  These restrict the conduction into the interior,  with heating by convection balancing cooling by re-radiation.  Fortunately,  at orbital entry speeds,  plasma radiation heating does not dominate,  and the plasma sheath is still more-or-less transparent to infrared radiation from the surface to space. 

The lateral and leeward surfaces see the least heating.  These had the white tiles and the white ceramic-fabric blankets.  There is very little physical scrubbing in a wake zone,  just immersion in very hot plasma.  It is still challenging,  just not as challenging as the windward surfaces,  in turn not as challenging as the leading edges and nosetip.

The "kicker" for the Shuttle was a sensitivity of survivability to AOA.  When I was a graduate student,  I and others found that the basic flow pattern was pretty much independent of the Shuttle's detailed nose shape.  All the noses were blunt,  we changed the shapes quite drastically otherwise,  and tested them in a hypersonic wind tunnel.  We found that below 20 degrees AOA,  the cockpit windscreen was directly exposed to the full wind blast.  It could NOT survive that. 

Between 20 and 40 degrees AOA,   flow separated coming over the nosetip,  and jumped over the cockpit roof,  leaving the cockpit roof and windscreen in a wake zone.  The windscreen could survive that. 

Above 40 degrees,  the lateral vortices along the sides of the nose pulled the jet coming over the nose back down as an attached jet,  slamming right into the windscreen again.  The windscreen could not survive that kind of heating. 

There was no point investigating beyond about 45 degrees AOA,  the wings would rip off.

This effect was one of many influences during Shuttle Columbia's breakup over Texas at about Mach 12 and 30-40 miles altitude.  It tumbled when it lost the damaged wing.  The next failure was the windscreen and cockpit roof.  Which is why the pieces of the 4 flight deck occupants came down between Dallas and Tyler.  The 3 mid-deck occupants were still alive in it when it was crushed by max-Q wind forces at about Mach 1 and about 20,000 feet,  near Tyler. 

Sometimes knowing too much is a curse.  Every time I think about this,  it upsets me.

GW

Last edited by GW Johnson (2021-10-03 11:05:07)


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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#1482 2021-10-03 19:23:35

SpaceNut
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#1483 2021-10-09 18:06:56

SpaceNut
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From: New Hampshire
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Posts: 25,943

Re: Starship is Go...

I finally took the time to figure out how to make the methane and oxygen from mars insitu materials.
Of course we need water and co2 with the sabatier reactor or something akin to one.
Here is the end results of setting up shop to get home for a starship

water gathered to make methane   oxygen    with co2 mT from the Atmosphere                                   
   540mT                      240mT    960mT       660 mt

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#1484 2021-10-11 10:03:59

GW Johnson
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From: McGregor, Texas USA
Registered: 2011-12-04
Posts: 4,858
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Re: Starship is Go...

Now do you understand why damp regolith is no practical source of water?  You process tons of regolith to get kg of water,  at best.  You need massive ice deposits,  which must be under the surface so as not to have sublimed away. 

There is the problem of salt and perchlorate contamination,  so the water purification process needs to go beyond just filtering out particulates.  The salt might aid electrolysis,  but the perchlorate doesn't help that.  There is PLENTY to do,  without the added burden of a diffuse resource spread thinly through tons of regolith.

And then there's the CO2 from the atmosphere.  You have to compress this up to working pressures in your sabatier reactor,  and you need to separate out the 3% other gases.  You won't be doing that compression with an ordinary compressor,  because the inlet pressure is 0.6% of an atmosphere,  not near 1 atmosphere.  That kind of compression looks more like a vacuum pump,  which is large machinery and lots of drive power for a tiny trickle of throughput massflow. You don't get hundreds of tons in under 2 years at grams per day.

You need to be processing ice into oxygen and hydrogen at the rate of 500-1000 kg per day to meet a 2 year timeline.  This ain't no bench-top laboratory play toy,  this is a big,  powerful piece of machinery processing half a ton to a ton of ice per day.  Which also means you mine-out half a ton to a ton of massive ice per day.  You can do that with a couple of backhoes.  But if that's 1% moisture in regolith,  you must process at least 50 to 100 tons of regolith per day,  which is patently absurd;  the numbers clearly say so. 

The best way to capture the CO2 is likely cooling the atmosphere to the CO2 condensation point.  You recover the dry ice as a solid,  which has separated-out the 3% "other gases" as effective noncondensibles.  Then you confine the dry ice in a tight-fitting can and warm it into gas again,  which inherently compresses it from the phase change,  into a usable pressure range.  Now you have a proper CO2 feed to your sabatier reactor.

You need to do this CO2 recovery at about 900-1000+ kg per day,  though.  This ain't no laboratory bench-top device we are talking about here.  This is a big,  powerful piece of machinery that has yet to be built and tested at all.  And it likely requires an astronaut crew to pack the dry ice into the tight cans.

You simply ain't gonna do this robotically!  There will be too many unknown problems to be solved on site.  Robots as we know them cannot handle that.  Humans can.  But only if they have adequate supplies and tools available.

These considerations are driven by the scale of the refilling requirement.  You don't do this with the dinky lab playtoys that scientists typically devise.  You do this with giant engineering machines and devices. They may be based on the little science toys,  but those scientists are not competent to design giant equipment like what is really needed.  Engineers are.

GW

Last edited by GW Johnson (2021-10-11 10:08:38)


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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#1485 2021-10-11 11:34:08

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
Posts: 25,943

Re: Starship is Go...

copied posts and commented in the other topic "Mars Water regolith soils 1 foot depth only" as to the challenges for mining the water from the soil.

Will add content there for the co2 processing

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#1486 2021-10-11 15:00:11

Oldfart1939
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Registered: 2016-11-26
Posts: 2,300

Re: Starship is Go...

To address the comments by GW, what will be needed are Pfaudler Stainless steel reactors in a 5,000 gallon capacity. These could be transferred to Mars by Starship, and with plenty of room to spare for additional cargo. Then there's the heating system to consider--after the refrigeration system. That's how I would approach the problem as an industrial chemist. I would first build a working model here on Earth as a "proof of concept" system before throwing it through several hundred million miles on Starship. Without a viable system, the mission is DOOMED!

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#1487 2021-10-11 16:58:35

Oldfart1939
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Registered: 2016-11-26
Posts: 2,300

Re: Starship is Go...

I might add as a supplemental comment: this type of equipment is what I was used to using in my nearly 50 year career as an Industrial and Manufacturing chemist. This wasn't the "kid stuff" that most people visualize when thinking of chemistry. My last employer has a row of 5,000 gallon reactors for manufacturing products on a SMALL industrial scale! My own plant wasn't quite so large and we only worked in the 50-75 scale until I sold the business to the guys with the really big reactors.

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#1488 2021-10-11 17:15:47

tahanson43206
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Registered: 2018-04-27
Posts: 10,760

Re: Starship is Go...

For OF1939 re #1486 and 1487

Would you be willing to help SpaceNut with his ambitious topic: Mars Water regolith soils 1 foot depth only

Your posts here suggest to me that you know most of what is needed to handle the material processing.

SpaceNut is pursuing the "worst case" scenario in the regolith topic.

GW Johnson is aiming for the lucky break option, of finding a frozen glacier under the proposed landing sites.

Even ** with ** the lucky break, all the chemistry is going to be practically the same.  The difference will be relative ease of acquiring water.

If you are willing to give SpaceNut a bit of coaching, I get the impression he is willing to do most of the work needed.

GW Johnson already tossed into the mix a suggestion for improving harvesting of CO2, by working with it as dry ice.

All this fits into "Starship is Go..." if we extend the topic to include ... "Starship is Going Home!!!!"

(th)

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#1489 2021-10-11 17:51:11

Oldfart1939
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Registered: 2016-11-26
Posts: 2,300

Re: Starship is Go...

I think that trying to harvest water from surface regolith is a fool's errand. I discussed my method of obtaining water years ago on this website. GW is absolutely correct. I proposed mining frozen chunks and transporting to an indoor and heated facility in wagons, and allow to simply thaw in a pressurized environment. Will need lotsa wagons per day, but something that's relatively lightweight or the purpose.

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#1490 2021-10-11 18:19:32

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

Re: Starship is Go...

I agree and NASA has good evidence of where we could easily uncover such ice deposits (in the Erebus Montes locality). There is strong evidence the ice is just a few feet below the surface in many locations. We can use robot earth movers, diggers, drillers and transporters.

How much ice is required to be mined  per sol?  I'm thinking it can't be more than 4 tons. I think a couple of 500Kg transporters should be able to handle that sort of tonnage with return trips during say a four hour working period.

Oldfart1939 wrote:

I think that trying to harvest water from surface regolith is a fool's errand. I discussed my method of obtaining water years ago on this website. GW is absolutely correct. I proposed mining frozen chunks and transporting to an indoor and heated facility in wagons, and allow to simply thaw in a pressurized environment. Will need lotsa wagons per day, but something that's relatively lightweight or the purpose.


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

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#1491 2021-10-12 09:57:18

Oldfart1939
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Registered: 2016-11-26
Posts: 2,300

Re: Starship is Go...

Louis, you 're thinking too small. I'm thinking of producing water for an entire colony, all in a big system, and this requires 10 20 tons per day of ice prior to processing. We've been taking about just the return fuel processing, and the scale you are talking about isn't close to what I think is needed.

In the long term, we want adequate water for drinking, sanitation and bathing, Aquaculture, Hydroponics, growing of crops. etc.

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#1492 2021-10-12 15:33:50

GW Johnson
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From: McGregor, Texas USA
Registered: 2011-12-04
Posts: 4,858
Website

Re: Starship is Go...

Here are the numbers from Spacenut's post 1483.  These are the quantities of water and carbon dioxide required to make 1200 tons of propellant to send a Starship from Mars back to Earth.  And don't kid yourself,  it will take all 1200 of those tons of propellant to get home. 

-------------------
Here is the end results of setting up shop to get home for a starship

water gathered to make methane   oxygen    with co2 mT from the Atmosphere                                   
   540mT                      240mT    960mT       660 mt
---------------------

Now,  let's make some assumptions about the mission and timing of events:

(1) Assume the Starship uses the 6-month trajectory,  not the nominal 8.5 Hohmann trajectory. 
(2) Assume the usual timing of launch windows -- every 22 months
(3) Assume the crew arrives from one launch window,  stays through the second,  and goes home during the third. 

That's a 44-month mission interval,  during which two 6-month trips must occur.  44-12 = 32 months = 960 days.  Just to make the return propellant (no other life support needs at all!!!) the crew must process water at 540 tons/960 days = 0.56 tons (TONS!!!) per day,  regardless of the weather or any other circumstances.  They must process carbon dioxide at the rate of 660 tons/960 days = 0.69 tons (TONS!!!) per day.  They CANNOT FAIL to meet those daily minimums,  or they do not not come home at the prescribed time. Which means they die.

That's a nice long stay on Mars,  not quite 3 years.  It may not be possible to stay that long,  for any of a variety of reasons,  especially during the first such missions.  So,  revise assumption 3 from every other launch opportunity to every opportunity.  The stay time on Mars is then 22 months less 12 months of 2-way travel = 10 months = 300 days.  They must make the propellant in 10 months,  or else they don't come home.  In turn,  that means a dead crew.

Here's the rates.  It's the same 1200 tons of propellant, regardless of stay time!  Water 540 tons/300 days = 1.80 tons (TONS!!!) per day.  CO2 660 tons/300 days = 2.20 tons (TONS!!!) per day. 

Now add life support needs for water and oxygen to that. 

This is going to take some big machinery to accomplish that task,  regardless of whether you return every opposition or every other opposition.  The numbers just DO NOT LIE!

So,  somebody tell me just exactly who is building machinery like that?  Or where they might be testing it? 

Failing any answers,  then somebody tell me just how many tons of supplies are we going to have to ship every 22 months to a crew sent one-way to Mars,  where they will live out their lives.

GW

Last edited by GW Johnson (2021-10-12 15:38:56)


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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#1493 2021-10-12 18:42:24

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

Re: Starship is Go...

True, but a large proportion of the non-fuel water can be recycled to high degree - maybe 90% or more. Water for "drinking, sanitation and bathing, Aquaculture, Hydroponics, growing of crops" can all be recycled. It's just water for fuel that is a one time use.

From the internet: " An acre of corn gives off about 3,000-4,000 gallons (11,400-15,100 liters) of water each day, " I also read that 97% of the water taken up by the plant from the soil is released back to the atmosphere via transpiration and other processes. As long as you aren't releasing water vapour to the Mars atmosphere, the absolute water requirement for all the activities you mention will be low.

Oldfart1939 wrote:

Louis, you 're thinking too small. I'm thinking of producing water for an entire colony, all in a big system, and this requires 10 20 tons per day of ice prior to processing. We've been taking about just the return fuel processing, and the scale you are talking about isn't close to what I think is needed.

In the long term, we want adequate water for drinking, sanitation and bathing, Aquaculture, Hydroponics, growing of crops. etc.


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

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#1494 2021-10-12 18:47:26

SpaceNut
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Posts: 25,943

Re: Starship is Go...

There is surplus oxygen with the double process but I have not done the calculations to see how far that goes with co2 cabin scrubbers.
As for the water we came with a supplemental batch could be had by clearing a few more yards of soil or ice but its just that.

The first mission out is an unmanned if you use Zubrin's plan with the partial fuel being started and in the bag before the crewed mission starts out. Its still a big if with the schedule of manufacturing of just to parts of the equation.

One thing to remember is to get the quantity you must also be able to store that key levels in what is on the surface for tanks which are in the ships. Plus while its processing you still need to make use of that same set of tanks to store and keep the finished product.

The unknowns is the scale or size in tonnes for the equipment to gather water no matter what that source is and its designed never to run out power source for it to work.

Next is also true for the co2 atmospheric scrubbing unit plus compression.

With the final keep multiple sabatier reactors to lessen the burn out of the catalysts in them while pushing them to the limits of manufacturing of fuel due to time crunch. These units still need power as well to function.

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#1495 2021-10-12 18:54:35

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

Re: Starship is Go...

No need to get too worked up about, let's say, a ton of water ice per sol would be my view. Probably even a single human being with a rock drill could harvest that amount of ice in a 4 hour shift, at 250 kgs per hour. Not that I think we will use human labour directly in that way. Maybe a couple of robotic drill rovers will be breaking up the ice.

Harvesting the CO2 may actually be more problematic. As you say, that would involve some fairly heavy duty machinery. It could well be a very significant proportion of the payload to Mars. Maybe 20-30% of 500 tons delivered to the surface. Pure guess on my part. The only thing I have to go on is that NASA had a plan I think for a machine that could harvest 3 Kgs of water vapour per sol and that weighed in at 800 Kgs IIRC.





GW Johnson wrote:

Here are the numbers from Spacenut's post 1483.  These are the quantities of water and carbon dioxide required to make 1200 tons of propellant to send a Starship from Mars back to Earth.  And don't kid yourself,  it will take all 1200 of those tons of propellant to get home. 

-------------------
Here is the end results of setting up shop to get home for a starship

water gathered to make methane   oxygen    with co2 mT from the Atmosphere                                   
   540mT                      240mT    960mT       660 mt
---------------------

Now,  let's make some assumptions about the mission and timing of events:

(1) Assume the Starship uses the 6-month trajectory,  not the nominal 8.5 Hohmann trajectory. 
(2) Assume the usual timing of launch windows -- every 22 months
(3) Assume the crew arrives from one launch window,  stays through the second,  and goes home during the third. 

That's a 44-month mission interval,  during which two 6-month trips must occur.  44-12 = 32 months = 960 days.  Just to make the return propellant (no other life support needs at all!!!) the crew must process water at 540 tons/960 days = 0.56 tons (TONS!!!) per day,  regardless of the weather or any other circumstances.  They must process carbon dioxide at the rate of 660 tons/960 days = 0.69 tons (TONS!!!) per day.  They CANNOT FAIL to meet those daily minimums,  or they do not not come home at the prescribed time. Which means they die.

That's a nice long stay on Mars,  not quite 3 years.  It may not be possible to stay that long,  for any of a variety of reasons,  especially during the first such missions.  So,  revise assumption 3 from every other launch opportunity to every opportunity.  The stay time on Mars is then 22 months less 12 months of 2-way travel = 10 months = 300 days.  They must make the propellant in 10 months,  or else they don't come home.  In turn,  that means a dead crew.

Here's the rates.  It's the same 1200 tons of propellant, regardless of stay time!  Water 540 tons/300 days = 1.80 tons (TONS!!!) per day.  CO2 660 tons/300 days = 2.20 tons (TONS!!!) per day. 

Now add life support needs for water and oxygen to that. 

This is going to take some big machinery to accomplish that task,  regardless of whether you return every opposition or every other opposition.  The numbers just DO NOT LIE!

So,  somebody tell me just exactly who is building machinery like that?  Or where they might be testing it? 

Failing any answers,  then somebody tell me just how many tons of supplies are we going to have to ship every 22 months to a crew sent one-way to Mars,  where they will live out their lives.

GW


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

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#1496 2021-10-12 22:22:54

Oldfart1939
Member
Registered: 2016-11-26
Posts: 2,300

Re: Starship is Go...

Louis-The scale of chemical process equipment required to process ice into usable water will astound you, as well as the quantities of starting material needed. GW gave a listing of how much water will be needed and getting a ton a day simply will not suffice. We can get Hydrogen and Oxygen from water by electrolysis, and the efficiencies are not really anywhere near quantitative. Every process has operational losses, and the efficiency is usually described by percent yield at the end. The difficult step will be getting enough CO2 to run through the Sabatier process and having hydrogen from the atmosphere.

This is a massive industrial undertaking at the scale of Starship's requirements. One Starship freighter will probably not be enough to handle a chemical processing facility in total weight and volume. A lot of this processing machinery is bulky.

Designing plants was part of what i did in industry. I designed the chemical process and with engineers, built systems that worked.

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#1497 2021-10-13 12:18:48

GW Johnson
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From: McGregor, Texas USA
Registered: 2011-12-04
Posts: 4,858
Website

Re: Starship is Go...

My point is that no one qualified to do this kind of work is actually working on making this large-scale machinery,  and testing it.   If people are going to go to Mars,  this machinery has to be already-proven when they go.  Otherwise,  you are killing a crew. 

Since no one is working on the real stuff,  just lab bench-top play toys,  the big machinery effort is starting from scratch.  It would take around a decade at the very least to build prototypes,  test them,  scale up to full size,  test them again,  then make sure they will really work at Martian conditions.  If it was started this very afternoon,  the gear wouldn't be ready until 2031 or 2032 at the very earliest.

There's no credibility to any claims that "Spacex is already working on this machinery". They have their hands more-than-full just trying to make the transportation work at all.  They are counting on "somebody else" to step up and make the machinery work in time to go on the missions. 

I'm telling you I see NOBODY actually doing that.

And don't tell me NASA has this stuff anywhere near ready to go.  There are few-to-no people at NASA qualified to actually do any of this sort of heavy machinery work.  That's why they hire contractors.  All the NASA labs have are some lab- bench-top play toys that they developed with some academics. There's NOTHING there anywhere near ready to do the job,  and NO ONE on these teams with the play toys that are qualified to develop large scale machinery from scratch.

Lessee,  if the Starship payload to Mars is about 150 metric tons,  and you send a bunch of tankers and one crewed ship,  then for 1200 tons,  you need to send 8 tankers at the very least.  If it's 100 tons,  you need 12 tankers.  Etc.  And they all become thrown-away relics on Mars.  Only the crewed vessel could come home. 

Add extra tankers for every one that crashes,  too.  It takes the whole 1200 tons of propellant to get that crewed Starship home;  the return voyage is more demanding than the outbound voyage,  in terms of delta-vee.  I've already run and reported the numbers for that,  too.

Each one of these 8+ to 12+ tankers and the one crewed ship have to be refilled on-orbit in order to depart for Mars.  That's 9+ to 13+ ships to refill,  to send 1 small crew to Mars.  Each one of those will require some 6 to 8 tankers to adequately fill it in low Earth orbit for departure.  6 tankers for each of 13 ships is 78 flights to send the 1 small crew to Mars. 

That's certainly NOT the way to do it!

So,  WHO EXACTLY is working on the big propellant-making plant machinery,  that simply has to be already-proven by the time men go to Mars?

The silence is deafening.

GW

Last edited by GW Johnson (2021-10-13 12:28:04)


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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#1498 2021-10-13 15:08:34

Oldfart1939
Member
Registered: 2016-11-26
Posts: 2,300

Re: Starship is Go...

GW-
That's a well argued statement. There is actually commercial equipment available that could be modified to do some of these processes, but not collection of CO2. I'm focusing on the water aspect of things, and as a corollary, will expand into the enormous amount of immediately needed energy. I don't think that Robert Zubrin has given quite enough thought to the scale and complexity of the  necessary process equipment, and correspondingly, the energy requirements.

If I were able to process images, I could do a block flow diagram for the entire water extraction process and the following conversion to Oxygen and the Hydrogen feedstock for the Sabatier reactor.

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#1499 2021-10-13 15:13:13

tahanson43206
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Registered: 2018-04-27
Posts: 10,760

Re: Starship is Go...

For OF1939 ....

Are you able to create the image you described?

If you can, then just email the image to NewMarsMember * gmail.com

I've had the privilege of assisting with display of images for others on the forum, and would be happy to do the same for you.

Especially!!! since the subject matter is so timely!

(th)

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#1500 2021-10-13 18:02:26

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 25,943

Re: Starship is Go...

The equipment is to modify the climework units which the blowers are most likely at or under 500 rpm to the same as the mars helicopter capable of 3 to 4000 rpm as that would allow a blower of co2 compatible to the units here on earth for mars use. The remaining part of the ubnit is untouched to perform the same act as we would on Mars.

RETTER.jpg

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

capture about 900 tons of CO2 annually  Fans push air through a filter system that collects CO2. When the filter is saturated, CO2 is separated at temperatures above 100 degrees Celsius.

edit
Climeworks’ new direct air capture plant, called Orca for the Icelandic word for energy, will be able to draw down 4,000 tons of carbon dioxide annually. That’s about how much 790 passenger vehicles might pump out in a year — not a huge amount, even though it’s the largest operation of its kind in the world1235138610.0.jpg

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