Constructing a human mission, a tonne at a time

SpaceNut · 2019-10-24 20:39:37

Sometimes its hard to find a topic even when you remember a key word...Tonne for the search word.

I was thinking about the topic as a result of some of the more recent nasa documents found for the other topics on solar, fuel plus oxygen creation and our kilowatt reactors along with many others.

I think many of these are less than the 2mT for payload size which seems to be possible with todays landing on mars technologies.

SpaceNut · 2019-12-30 21:20:03

Red dragon was a capsule that when full was close to 13mT including payload as calculated to be able to land on mars.

SpaceNut · 2019-12-30 21:25:05

https://ntrs.nasa.gov/archive/nasa/casi … 008862.pdf
An Overview of Mars Vicinity Transportation Concepts for a Human Mars Mission

Seems the RL10 version can handle LH2 or LCh4 with Lox just fine as matched for a mars landing.

https://ntrs.nasa.gov/archive/nasa/casi … 024099.pdf
LIQUID OXYGEN/LIQUID METHANE COMPONENT TECHNOLOGY DEVELOPMENT AT MSFC

https://www.lockheedmartin.com/content/ … ncepts.pdf
Lockheed Mars Base camp
Concept ship is multi deck internal sort along the BFR starship in appeareance

http://www.niac.usra.edu/files/studies/ … 40Rice.pdf
ADVANCED SYSTEM CONCEPT FOR TOTAL ISRU BASED PROPULSION AND POWER SYSTEMS FOR UNMANNED AND MANNED EXPLORATION

https://www.lpi.usra.edu/lunar/document … 107050.pdf
An Accelerated Development, Reduced Cost Approach to Lunarmars Exploration Using a Modular NTR-Based Space Transportation System

https://www.aiaa.org/docs/default-sourc … e15a8a6e_0

Project Argonaut: A Proposal for a Mars Sample Return Mission

kbd512 · 2019-12-31 01:58:24

SpaceNut,

Despite our numerous barbs directed at "old space" contractors for their apparent lack of progress, the more I weigh the trade-offs of Lockheed-Martin's proposal for Mars exploration, the more cold hard logic I find backing it. I love the sheer audacity of SpaceX's Mars colonization plan, but I just can't see how it's a realistic plan until we establish "ground truth", as GW would say, regarding the availability of natural resources on Mars. An enormous logical leap is required from knowing that a resource exists somewhere on a planet that we've never set foot on to utilization of that resource to produce a finished product at an industrial scale in a way that's never been done on Earth, even one as simple as common rocket propellants.

LM's Mars Base Camp seems like the most realistic at this time. It's using existing technology from ISS and Orion in a novel way. We should still use SpaceX's reusable boosters to keep the launch costs sane.

In a world where Congress did things that made sense, SpaceX would develop a reusable Saturn V class Raptor-powered booster, Boeing would put a composite tank partially reusable SLS core stage atop SpaceX's booster, ULA would figure out how to recover our prized RS-25's, and we'd have a 250t class "mostly-reusable" super heavy lift vehicle to put Mars Base Camp into a halo orbit around Earth so it could easily spiral out to Mars using Aerojet-Rocketdyne's new 100kW ion engines that have passed every test with flying colors. Bigelow would provide the inflatable habitat modules since we don't have anything else with the volume-to-mass efficiency of an inflatable. Northrop-Grumman would develop the lander since they're the only company to ever land anything carrying humans aboard on another planet. After being told what to do, that would be the end of involvement from Congress and NASA until certain project testing points were arrived at in order to curtail gold plating of the solutions. We could allow everyone to work on something within their institutionalized knowledge base, rather than establishing prime or preferred contractors for tasks that are so complicated in nature that no single contractor has the requisite knowledge to complete it. The Apollo program was a national effort.

After we decided we were going to go to the moon, we hammered out the details and made whatever concessions were required to achieve that goal on a fixed schedule. It turns out that perfection wasn't required and "good enough for government work" was also "good enough to get the job done". We started with a tool set that was barely acceptable for executing the mission, but refined or upgraded the basic solution with each successive mission to enhance our mission capabilities. We simply couldn't afford to sustain that program using 1960's technology, but we're 60 years beyond Apollo and our technology is incomparably better than it was. I can't think of an excuse that passes muster regarding why it is that we're not deep into full dress rehearsal testing and approaching the first mission in our Mars exploration campaign.

louis · 2019-12-31 05:58:49

I think we can be far more confident of "ground truth" than sceptics here may allow.

The water signatures are powerful and would require us rethinking the whole of our chemistry for them to be wrong. NASA ain't stupid when it comes to global surveying. They'll be able to match visual identification of ice with satellite observations of water signatures. And of course all these satellite observation tools will have been tested around Earth first.

Likewise we know what the concentration of CO2 in the atmosphere is.

Furthermore, the Space X mission allows for cargo Starships to land on Mars 2 years in advance of humans - which will give further proof of "ground truth" before humans set off for Mars.

What more do we really need to know in terms of rocket fuel manufacture? It's true that manufacture on what might fairly be described as an industrial scale is challenging (maybe around 1000 tons) but on the other hand we've never had a situation where 500 tons of cargo is going to be landed on a celestial body as part of a single mission. That's a huge game changer. It means you take all the manufacturing and processing equipment you require plus spare parts.

Space X is going to win this slam-dunk style.

kbd512 wrote:

SpaceNut,
Despite our numerous barbs directed at "old space" contractors for their apparent lack of progress, the more I weigh the trade-offs of Lockheed-Martin's proposal for Mars exploration, the more cold hard logic I find backing it. I love the sheer audacity of SpaceX's Mars colonization plan, but I just can't see how it's a realistic plan until we establish "ground truth", as GW would say, regarding the availability of natural resources on Mars. An enormous logical leap is required from knowing that a resource exists somewhere on a planet that we've never set foot on to utilization of that resource to produce a finished product at an industrial scale in a way that's never been done on Earth, even one as simple as common rocket propellants.
LM's Mars Base Camp seems like the most realistic at this time. It's using existing technology from ISS and Orion in a novel way. We should still use SpaceX's reusable boosters to keep the launch costs sane.
In a world where Congress did things that made sense, SpaceX would develop a reusable Saturn V class Raptor-powered booster, Boeing would put a composite tank partially reusable SLS core stage atop SpaceX's booster, ULA would figure out how to recover our prized RS-25's, and we'd have a 250t class "mostly-reusable" super heavy lift vehicle to put Mars Base Camp into a halo orbit around Earth so it could easily spiral out to Mars using Aerojet-Rocketdyne's new 100kW ion engines that have passed every test with flying colors. Bigelow would provide the inflatable habitat modules since we don't have anything else with the volume-to-mass efficiency of an inflatable. Northrop-Grumman would develop the lander since they're the only company to ever land anything carrying humans aboard on another planet. After being told what to do, that would be the end of involvement from Congress and NASA until certain project testing points were arrived at in order to curtail gold plating of the solutions. We could allow everyone to work on something within their institutionalized knowledge base, rather than establishing prime or preferred contractors for tasks that are so complicated in nature that no single contractor has the requisite knowledge to complete it. The Apollo program was a national effort.
After we decided we were going to go to the moon, we hammered out the details and made whatever concessions were required to achieve that goal on a fixed schedule. It turns out that perfection wasn't required and "good enough for government work" was also "good enough to get the job done". We started with a tool set that was barely acceptable for executing the mission, but refined or upgraded the basic solution with each successive mission to enhance our mission capabilities. We simply couldn't afford to sustain that program using 1960's technology, but we're 60 years beyond Apollo and our technology is incomparably better than it was. I can't think of an excuse that passes muster regarding why it is that we're not deep into full dress rehearsal testing and approaching the first mission in our Mars exploration campaign.

SpaceNut · 2019-12-31 10:41:19

Its the surface stay which has the great impact on payload mass to the surface per crew man and to what percentage of recycling of thpse resource of the payload are recycled offsets some of the payload mass. Then is impact is what is brought that makes use of isitu materials which shifts the payload mass once more.

Launch mass from earth is impacted by where the mass must reside in the path to and from mars and not just its surface stay.

Return mass from mars is dictated by insitu materials used and payload being returned to earth by direct return or by rendevous on the path with stationed goods and gear for the final journey home.

mission surface cycles are 30 day stay, 60 day stay, 500 day surface and 600 days on the surface with the first two spending the most time in 0 G which is not a good thing for man. With the later pair taking about 6 to 8 months in both direction of travel. The mission for insitu needs to have fuel complete in 500 days if leaving in 600. Thou no one talks about that lead time production of fuels as its the energy expended that rises sharply with insitu time shortening.

Hegding the time factor and energy is landing in advance a power ISPP plant to have that part taken care of automatically before man even lands and then any choice of mission is sharply dependant on resources landed with the crew instead.

kbd512 · 2019-12-31 14:35:53

Louis,

Do you have any idea whether we're seeing pure water, salt water, or frozen mud?

If so, then cite the source you're getting your information from. I don't even need a link, just the title of the paper you've read.

So far as I know, we use spectral analysis rather than radar to determine exact chemical compositions. A radar return off of a lake or ocean can tell you that you're looking at water versus rock, but it can't tell you much of anything about what the water or rock contains. Unless microwaves recently became far more sophisticated than what I know of them, your article of faith surrounding this matter doesn't constitute a persuasive argument regarding what the scientists who are actually working on this problem have to say about their own work. I've quoted them here so everyone else can read about what they've actually stated.

Here's my source:

Space.com - Water on Mars: Exploration & Evidence by Nola Taylor Redd

From the article (my commentary within the quotation begins with asterisks):

"This subsurface anomaly on Mars has radar properties matching water or water-rich sediments," Roberto Orosei, principal investigator of the MARSIS experiment and lead author of the new research, said in a statement.
* translation: we have no clue about whether we're looking at water or hydrated minerals
MARSIS also revealed the presence of a subsurface lake among the pockets. According to the radar echoes, the lake is no more than 12.5 miles (20 km) across, buried nearly a mile beneath the surface. The scientists aren't certain of the lake's depth, but they have confirmed that it is at least 3 feet (1 meter) deep. According to the researchers, the lake must have salt to keep from freezing.
* translation: getting at this subsurface water, assuming it exists in usable form (liquid or solid), could be a lot like drilling a shallow oil well, with a very narrow "pay zone" that we see so often when we drill wells here on Earth, thus requiring the same types of equipment needed to drill a shallow oil well (a brine based mud to drill with, mud pits, stainless steel pipe, shakers and screens to remove cuttings, something akin to concrete to case or line the bore hole to prevent it from collapsing, etc)
"This is just one small study area; it is an exciting prospect to think there could be more of these underground pockets of water elsewhere, yet to be discovered," Orosei said.
Not all researchers are as certain about the presence of liquid water.
"I think it's a very, very persuasive argument, but it's not a conclusive or definitive argument," Steve Clifford, a Mars researcher at the Planetary Science Institute in Arizona, told Space.com. "There's always the possibility that conditions that we haven't foreseen exist at the base of the cap and are responsible for this bright reflection."
* translation: although we really want to believe it's water, we still have no clue (NO GROUND TRUTH)
More than three decades ago, Clifford proposed that Mars could harbor liquid water beneath its polar caps in the same way that Earth does. On Earth, lakes beneath the Antarctic and Greenland ice sheets are created when heat from within the planets melt the glaciers in patches. Clifford told Space.com that a similar scenario could happen beneath the Martian polar ice caps.
"The bright spot seen in the MARSIS data is an unusual feature and extremely intriguing," Jim Green, NASA's chief scientist, said in a statement. "It definitely warrants further study. Additional lines of evidence should be pursued to test the interpretation."
* translation: someone needs to drill an exploratory well, maybe several wells, before we start betting lives on using whatever is down there to get our people home
"We hope to use other instruments to study it further in the future," Green said.

If we obtain usable quantities of water with usable characteristics (something we can actually extract), I will write my Congressman and my President if I have to in order to ensure that SpaceX can go buck wild with their plans. Until then, as an American tax payer who pays to fund these missions (SpaceX has received American tax money to develop their rocket engines and nearly everything else except the Falcon Heavy and Starship vehicles), I want ground truth. We've already killed enough astronauts on false assumptions and assertions.

If SpaceX wishes to conduct exploratory missions to ensure they hit that pay zone, then I'm onboard with that. Until they have demonstrated the ability to extract water in the required quantities, they need to have a backup plan in place to return our astronauts to Earth. If I were a NASA or FAA administrator, I would flatly refuse to gamble the lives of the finest men and women Earth has produced on blind faith that we'll somehow get them back. Furthermore, I would refuse to give our Legislature or Executive any excuse at all to halt progress on Mars exploration and eventual colonization. People need to get it through their heads that astronauts are real people with families who care about them, not poker chips to place bets with.

Lockheed-Martin is not about to steal any glory from SpaceX. Defense contractors could care less about colonizing Mars. They're a bunch of scientists who want to understand Mars and as of right now they have a better plan than SpaceX for ensuring that we return our astronauts to Earth.

When you can show me a patent for or research paper describing the testing of one of these new MW-class space-rated Sabatier reactors, I'll begin to believe that someone is serious about using LCH4 ISPP. Until you do that, you haven't convinced me that we know what we need to know about making rocket propellant on Mars. You keep talking about this stuff as if it's already happened, but we'd have flight-tested hardware laying around everywhere if that was the case. Thus far, I've seen nothing of the sort.

SpaceX's Dragon 2 commercial crew capsule exploded in a fireball during the last abort test and Boeing can't seem to synchronize a clock correctly or write a software program robust enough to determine when their capsule is out of position for its orbital insertion burn. I think I rightly question whether or not we're ready to send humans back into space at all, much less tens of millions of miles from home to the surface of another planet, while relying on equipment that nobody has a prototype of to return them to Earth.

louis · 2019-12-31 15:58:10

Haven't got chapter and verse for you here and now but this is my understanding:

1. Water/water ice gives off a particular signal - hydrogen atoms IIRC. That is picked up on spectral analysis. Obviously the scientists who interpret such data are used to tying in observation data with actual presence of water/ice.

2. Ground radar can reveal the structure of ice.

3. The purity of the ice is suggested by the radar results. Mixed regolith and ice will give a different signal from pure ice.

4. You get typical results for ice where purity increases below the surface. At the regolith/ice boundary you get impure ice.

5. Regolith with ice crystals gives a different radar signal from ice.

6. Photo observations can reveal geological clues that confirm or contradict the other data. For instance the walls of crater with an ice lake in it typically bulge.

7. Computer analysis of multiple satellite photos of the same location allow analysts to resolve images of objects down to a few cms.

8. Solid rock gives a different radar signature to sand, loose regolith and other formations.

kbd512 wrote:

Louis,
Do you have any idea whether we're seeing pure water, salt water, or frozen mud?
If so, then cite the source you're getting your information from. I don't even need a link, just the title of the paper you've read.
So far as I know, we use spectral analysis rather than radar to determine exact chemical compositions. A radar return off of a lake or ocean can tell you that you're looking at water versus rock, but it can't tell you much of anything about what the water or rock contains. Unless microwaves recently became far more sophisticated than what I know of them, your article of faith surrounding this matter doesn't constitute a persuasive argument regarding what the scientists who are actually working on this problem have to say about their own work. I've quoted them here so everyone else can read about what they've actually stated.
Here's my source:
Space.com - Water on Mars: Exploration & Evidence by Nola Taylor Redd
From the article (my commentary within the quotation begins with asterisks):
"This subsurface anomaly on Mars has radar properties matching water or water-rich sediments," Roberto Orosei, principal investigator of the MARSIS experiment and lead author of the new research, said in a statement.
* translation: we have no clue about whether we're looking at water or hydrated minerals
MARSIS also revealed the presence of a subsurface lake among the pockets. According to the radar echoes, the lake is no more than 12.5 miles (20 km) across, buried nearly a mile beneath the surface. The scientists aren't certain of the lake's depth, but they have confirmed that it is at least 3 feet (1 meter) deep. According to the researchers, the lake must have salt to keep from freezing.
* translation: getting at this subsurface water, assuming it exists in usable form (liquid or solid), could be a lot like drilling a shallow oil well, with a very narrow "pay zone" that we see so often when we drill wells here on Earth, thus requiring the same types of equipment needed to drill a shallow oil well (a brine based mud to drill with, mud pits, stainless steel pipe, shakers and screens to remove cuttings, something akin to concrete to case or line the bore hole to prevent it from collapsing, etc)
"This is just one small study area; it is an exciting prospect to think there could be more of these underground pockets of water elsewhere, yet to be discovered," Orosei said.
Not all researchers are as certain about the presence of liquid water.
"I think it's a very, very persuasive argument, but it's not a conclusive or definitive argument," Steve Clifford, a Mars researcher at the Planetary Science Institute in Arizona, told Space.com. "There's always the possibility that conditions that we haven't foreseen exist at the base of the cap and are responsible for this bright reflection."
* translation: although we really want to believe it's water, we still have no clue (NO GROUND TRUTH)
More than three decades ago, Clifford proposed that Mars could harbor liquid water beneath its polar caps in the same way that Earth does. On Earth, lakes beneath the Antarctic and Greenland ice sheets are created when heat from within the planets melt the glaciers in patches. Clifford told Space.com that a similar scenario could happen beneath the Martian polar ice caps.
"The bright spot seen in the MARSIS data is an unusual feature and extremely intriguing," Jim Green, NASA's chief scientist, said in a statement. "It definitely warrants further study. Additional lines of evidence should be pursued to test the interpretation."
* translation: someone needs to drill an exploratory well, maybe several wells, before we start betting lives on using whatever is down there to get our people home
"We hope to use other instruments to study it further in the future," Green said.
If we obtain usable quantities of water with usable characteristics (something we can actually extract), I will write my Congressman and my President if I have to in order to ensure that SpaceX can go buck wild with their plans. Until then, as an American tax payer who pays to fund these missions (SpaceX has received American tax money to develop their rocket engines and nearly everything else except the Falcon Heavy and Starship vehicles), I want ground truth. We've already killed enough astronauts on false assumptions and assertions.
If SpaceX wishes to conduct exploratory missions to ensure they hit that pay zone, then I'm onboard with that. Until they have demonstrated the ability to extract water in the required quantities, they need to have a backup plan in place to return our astronauts to Earth. If I were a NASA or FAA administrator, I would flatly refuse to gamble the lives of the finest men and women Earth has produced on blind faith that we'll somehow get them back. Furthermore, I would refuse to give our Legislature or Executive any excuse at all to halt progress on Mars exploration and eventual colonization. People need to get it through their heads that astronauts are real people with families who care about them, not poker chips to place bets with.
Lockheed-Martin is not about to steal any glory from SpaceX. Defense contractors could care less about colonizing Mars. They're a bunch of scientists who want to understand Mars and as of right now they have a better plan than SpaceX for ensuring that we return our astronauts to Earth.
When you can show me a patent for or research paper describing the testing of one of these new MW-class space-rated Sabatier reactors, I'll begin to believe that someone is serious about using LCH4 ISPP. Until you do that, you haven't convinced me that we know what we need to know about making rocket propellant on Mars. You keep talking about this stuff as if it's already happened, but we'd have flight-tested hardware laying around everywhere if that was the case. Thus far, I've seen nothing of the sort.
SpaceX's Dragon 2 commercial crew capsule exploded in a fireball during the last abort test and Boeing can't seem to synchronize a clock correctly or write a software program robust enough to determine when their capsule is out of position for its orbital insertion burn. I think I rightly question whether or not we're ready to send humans back into space at all, much less tens of millions of miles from home to the surface of another planet, while relying on equipment that nobody has a prototype of to return them to Earth.

kbd512 · 2020-01-01 13:52:28

Louis,

First, Happy New Year. Here's to hoping 2020 will be a great year for human space flight and exploration.

Second, the only thing radar tell us is the strength of the return. Basically, we're measuring the reflectivity of the material we're bouncing those waves off of. Different materials typically reflect electromagnetic waves of a particular frequency more strongly than others based upon their density, shape, and other properties of the material, such as electrical conductivity. However, there are still practical limitations as to what that actually tells us. If we have two different objects with the same bulk density and shape, then absent other properties that would affect the strength of the return, the return will be the same. That's why some ground truth needs to be established. Drilling a single well to find out what's down there is worth more to me than all the radar returns in the world.

I noticed you still haven't addressed the apparent absence of a flight-rated MW-class Sabatier reactor and drilling equipment suitable to dig a well a mile deep. Even if we operated off of the assumption that the "water radar return" was indeed water and it's exactly where the radar says it is and it's primarily a briny liquid or ice that we can actually pump, the drilling equipment is still required to obtain it. I seriously doubt that SpaceX has any practical experience drilling wells and using tunnel boring machines doesn't count.

We need a precursor exploration campaign bridging the gap between never having set foot on Mars and full scale colonization efforts that depend on ISRU and ISPP for success. Lockheed-Martin's approach is more suitable for exploration since it makes all propellant from an onboard water store after achieving orbit around Mars, transfers it to a pair of landers or Earth return kick stages as required, and those landers can then visit multiple different sites to determine what resources are present from direct observation. It's not as grandiose as SpaceX's plan, but far less risky. If SpaceX is not able to make propellant, reason unimportant, then Starship isn't coming home and the rest of their plan falls apart.

SpaceNut · 2020-01-01 14:45:22

To go with kbd512's happy new years for space flight for man is a to all of the newmars members to have a great year as well.

Map of the H2O concentration in the upper few tens of centimeters of the martian surface, as measured from orbit by the Mars Odyssey Gamma Ray Spectrometer (GRS). Equatorial Mars (about 45 degrees north and south) contains between 2 and 7 wt.% H2O, and polar regions contain much more. The GRS actually measured hydrogen (H), but those concentrations have been converted to H2O. In reality, much of the water may be in the form of OH bound in minerals.

Think about the microwave oven and how it works. The water in the food is caused to vibrate to make the heat energy from the beam wave length to cause the food to get hot. However radar is a different set of frequencies that tend to bounce and some what penitrate what it strikes. Its the reflected bounce which is different for each elemental materials. So anything that has both 2H2 and O2 present will give the false return signal of water as we are not tuning the wave to only reflect off from a particular element only.

The same thing happens for sound to ultra sound frequencies as they reflect as the density changes as more water is present to give the reflected density image that is seen.

For the sabatier to even have a chance to work we need to have comparible compression and cooling cryrogenics units which will suck up power as well. Heat processing and regolith moving if we do not have drilling capable of the depths of mars hidden best guess water.

We truely need to look at not just brute force solutions of energy but low energy as well to solve some of what we need on mars as well as no energy solutions where applicable.

Using the cold of mars for anything needing to be cooled means a low energy working fluid and exchanger to do what we need. The same is true in that if we need heat to not just dump the heat that we removed by mars cold but to store it for other uses.

louis · 2020-01-01 18:55:24

Yes Happy New Year and to you and all at New Mars Forums...may 2020 be a year of significant progress towards a human presence on Mars!

I've never been an advocate of well drilling. I've favoured the use of bulldozer rovers to break through crater walls or other inclines and reveal the ice. You then dig out the ice in large lumps, breaking it first with powerful pneumatic drills/hammers. Once you locate your ice, this would be a very efficient way of extracting water ice. Robot rovers would take the ice back to the central processing facility located near the original landing point.

I think with a 500 ton mission you can probably also operate a dehumidifier to extract water from the atmosphere and bring equipment for regolith ice extraction.

The locations for landing in Amazonis Planitia under active consideration by Space X have lots of likely ice features within range. After maybe 50 sols of setting up the base, exploration Rovers could set out and and check locations for water ice presence using a range of testing equipment.
They will then identify the most promising sites, at which points you bring in your robot bulldozers, diggers and hammers.

kbd512 wrote:

Louis,
First, Happy New Year. Here's to hoping 2020 will be a great year for human space flight and exploration.
Second, the only thing radar tell us is the strength of the return. Basically, we're measuring the reflectivity of the material we're bouncing those waves off of. Different materials typically reflect electromagnetic waves of a particular frequency more strongly than others based upon their density, shape, and other properties of the material, such as electrical conductivity. However, there are still practical limitations as to what that actually tells us. If we have two different objects with the same bulk density and shape, then absent other properties that would affect the strength of the return, the return will be the same. That's why some ground truth needs to be established. Drilling a single well to find out what's down there is worth more to me than all the radar returns in the world.
I noticed you still haven't addressed the apparent absence of a flight-rated MW-class Sabatier reactor and drilling equipment suitable to dig a well a mile deep. Even if we operated off of the assumption that the "water radar return" was indeed water and it's exactly where the radar says it is and it's primarily a briny liquid or ice that we can actually pump, the drilling equipment is still required to obtain it. I seriously doubt that SpaceX has any practical experience drilling wells and using tunnel boring machines doesn't count.
We need a precursor exploration campaign bridging the gap between never having set foot on Mars and full scale colonization efforts that depend on ISRU and ISPP for success. Lockheed-Martin's approach is more suitable for exploration since it makes all propellant from an onboard water store after achieving orbit around Mars, transfers it to a pair of landers or Earth return kick stages as required, and those landers can then visit multiple different sites to determine what resources are present from direct observation. It's not as grandiose as SpaceX's plan, but far less risky. If SpaceX is not able to make propellant, reason unimportant, then Starship isn't coming home and the rest of their plan falls apart.

SpaceNut · 2020-01-01 19:04:22

louis · 2020-01-01 19:21:02

Yes Happy New Year SpaceNut and thanks for all your hard work keeping this site going.

Further to my reply to kbd:

https://www.space.com/mars-water-ice-map.html

"The new map is based on data from two long-running spacecraft: NASA's Mars Reconnaissance Orbiter and Mars Odyssey. Each spacecraft used heat-sensitive instruments to find the ice, because buried ice changes the temperature of the surface. To be sure that it was ice they were seeing, the scientists cross-referenced their work with other data — like ice seen in radar instruments and Mars Odyssey's gamma-ray spectrometer, which is optimized for spotting water ice deposits."

I think scepticism about water/water ice presence on Mars was valid a few decades ago but we now have such a wealth of data and a strong theoretical basis for our knowledge that is more like the way tectonic plate theory has come to be accepted. To set it to one side would now be impossible. I think the same goes for the water ice data. We know why it's there, how it got there, how close it is to the surface, how pure it is and so on. We might not be able to identify a water ice location to within 100 metres but within 1 km, I think we probably can.

SpaceNut wrote:

To go with kbd512's happy new years for space flight for man is a to all of the newmars members to have a great year as well.
http://www.psrd.hawaii.edu/WebImg/Mars-GRSwatermap.jpg
Map of the H2O concentration in the upper few tens of centimeters of the martian surface, as measured from orbit by the Mars Odyssey Gamma Ray Spectrometer (GRS). Equatorial Mars (about 45 degrees north and south) contains between 2 and 7 wt.% H2O, and polar regions contain much more. The GRS actually measured hydrogen (H), but those concentrations have been converted to H2O. In reality, much of the water may be in the form of OH bound in minerals.
Think about the microwave oven and how it works. The water in the food is caused to vibrate to make the heat energy from the beam wave length to cause the food to get hot. However radar is a different set of frequencies that tend to bounce and some what penitrate what it strikes. Its the reflected bounce which is different for each elemental materials. So anything that has both 2H2 and O2 present will give the false return signal of water as we are not tuning the wave to only reflect off from a particular element only.
The same thing happens for sound to ultra sound frequencies as they reflect as the density changes as more water is present to give the reflected density image that is seen.
For the sabatier to even have a chance to work we need to have comparible compression and cooling cryrogenics units which will suck up power as well. Heat processing and regolith moving if we do not have drilling capable of the depths of mars hidden best guess water.
We truely need to look at not just brute force solutions of energy but low energy as well to solve some of what we need on mars as well as no energy solutions where applicable.
Using the cold of mars for anything needing to be cooled means a low energy working fluid and exchanger to do what we need. The same is true in that if we need heat to not just dump the heat that we removed by mars cold but to store it for other uses.

kbd512 · 2020-01-01 21:03:52

Louis,

I've never claimed that Mars doesn't have water. I am claiming that the most energy efficient way to collect water is to obtain liquid water or, failing that, ice. The most significant concentrations of liquid water or water ice are near the poles or a kilometer or more below the surface. If you look at that map SpaceNut provided, the water concentration in the regolith is less than that of some of the driest deserts here on Earth, which happens to be most places on Mars that aren't near the poles.

After you collect the regolith, how do you intend to extract the water?

If a standard cubic meter of surface regolith contains 10% water, that's 152kg per cubic meter. Unless your extraction process is 100% efficient, that's not what you're actually going to collect, either. Starship requires 240t of LCH4, CH4 is about 25% Hydrogen by weight, so we're talking about nearly 600t of water (H2O is about 11% Hydrogen by Weight) to extract 60t of Hydrogen. At a bare minimum, that's nearly 4,000 cubic meters of regolith.

If you were able to extract 50% of the water from a cubic meter of regolith, at a concentration of 10%- far above what it actually is in most places and presuming we're not looking at hydrated minerals, then we'd need to process 8,000 cubic meters of regolith in 630 days, or about 12.7 cubic meters per day. If we're using solar power, then we have to do that and extract whatever water we can get in about 8 hours time. We do have machines that can move that much mass of material here on Earth, but they're the size / weight of big rigs and require similar amounts of power. In short, what you're describing is a fairly significant mining activity that can never fall behind due to busted equipment or lack of power.

I'm sure it's possible, but you're talking about doing this from Day 1 on Mission 1 and maintaining that level of productivity for 2 years straight, no breaks, despite the fact that mining companies in places like Canada have a hard time managing stuff like that here on Earth. It seems pretty far-fetched to me and if it doesn't work out as well as you think it will, then nobody is coming back. While I admire your enthusiasm for SpaceX's approach, I want to see some tests that show this working here on Earth first.

louis · 2020-01-02 05:48:58

...and I'm not claiming that the most energy efficient way to access water is not via a drilled well. But for Mission One? For the first mission I think you need some brute force technology. Obviously Space X and NASA are looking at landing sites in zones where the regolith ice content is over 4% and where they have strong evidence for ice accumulations e.g. as ice lakes in craters.

The ice purity observed by satellite radar is much better than you allow. Where ice has been exposed at the surface, it appears to be about 99% pure in places:

https://www.space.com/7333-water-ice-ex … aters.html

600 tons of water.... Once you have found your ice maybe you are achieving 80% purity let's say. So add on 150 tons, to make it 750 tons of water to be collected. Over a 500 sols period that would be 1.5 tons a day. Over a four hour "working" period that would be 375 kgs of ice per hour to be collected. Given a mini digger might easily scoop up 100 kgs a time, that is not going to be a problem. The likelihood is the job could be done within 100 sols, in reality.

The alternative if a pure ice deposit can't be found is probably a mix of dehumidifier extraction from the atmosphere and a long hard slog with extraction of ice from the surface regolith. With a team of maybe 10 x 2 ton robot rovers cabled up to a power supply, I don't think that 16 cubic metres or even 32 cubic metres per sol, working over maybe 10 hours per sol, is that challenging. It could be pretty much 100% robotic.

But I am pretty confident that very pure ice deposits can be exposed at the right areas.

kbd512 wrote:

Louis,
I've never claimed that Mars doesn't have water. I am claiming that the most energy efficient way to collect water is to obtain liquid water or, failing that, ice. The most significant concentrations of liquid water or water ice are near the poles or a kilometer or more below the surface. If you look at that map SpaceNut provided, the water concentration in the regolith is less than that of some of the driest deserts here on Earth, which happens to be most places on Mars that aren't near the poles.
After you collect the regolith, how do you intend to extract the water?
If a standard cubic meter of surface regolith contains 10% water, that's 152kg per cubic meter. Unless your extraction process is 100% efficient, that's not what you're actually going to collect, either. Starship requires 240t of LCH4, CH4 is about 25% Hydrogen by weight, so we're talking about nearly 600t of water (H2O is about 11% Hydrogen by Weight) to extract 60t of Hydrogen. At a bare minimum, that's nearly 4,000 cubic meters of regolith.
If you were able to extract 50% of the water from a cubic meter of regolith, at a concentration of 10%- far above what it actually is in most places and presuming we're not looking at hydrated minerals, then we'd need to process 8,000 cubic meters of regolith in 630 days, or about 12.7 cubic meters per day. If we're using solar power, then we have to do that and extract whatever water we can get in about 8 hours time. We do have machines that can move that much mass of material here on Earth, but they're the size / weight of big rigs and require similar amounts of power. In short, what you're describing is a fairly significant mining activity that can never fall behind due to busted equipment or lack of power.
I'm sure it's possible, but you're talking about doing this from Day 1 on Mission 1 and maintaining that level of productivity for 2 years straight, no breaks, despite the fact that mining companies in places like Canada have a hard time managing stuff like that here on Earth. It seems pretty far-fetched to me and if it doesn't work out as well as you think it will, then nobody is coming back. While I admire your enthusiasm for SpaceX's approach, I want to see some tests that show this working here on Earth first.

SpaceNut · 2020-01-02 18:54:49

Since the mission stillis large scale BFR starship or small Dragon sized and in between for ship size we are still looking at the how to with a set of garentees for crew that must be there on a first human mission to have the safe guard of being able to survive and to return home with the least amount of risk.

So with the 2020 rover landing and moxie running successfully then do we settle on LCO and LOX for a known fuels to get back home as that is all that we have proven and use the unused water from this mission to set the stage for the next mission which could at that point do LCH4 and LOX for the return home.

Its about energy and if its not going to be anything but RTG and Solar we are going to think about how its best used.

kbd512 wrote:

The input energy requirement for LOX/LCO manufacture is around 110MJ/kg of payload delivered to LMO and LOX/LCH4 is 460MJ/kg of payload delivered to LMO.

louis · 2020-01-02 19:51:33

It's Space X and methane or nothing for the foreseeable future. No other agency has put together a credible mission architecture. I completely discount the Lockheed nonsense.

There is nothing outrageous in the Space X mission model, given they are taking 500 tons to the surface. The only question of note is: is there accessible water ice? If not, the mission will fail. If the answer is yes (and everything points to there being substantial ice deposits just below the surface in the favoured landing sites in Amazonis Planitia) then there is no problem - the mission will succeed.

SpaceNut wrote:

Since the mission stillis large scale BFR starship or small Dragon sized and in between for ship size we are still looking at the how to with a set of garentees for crew that must be there on a first human mission to have the safe guard of being able to survive and to return home with the least amount of risk.
So with the 2020 rover landing and moxie running successfully then do we settle on LCO and LOX for a known fuels to get back home as that is all that we have proven and use the unused water from this mission to set the stage for the next mission which could at that point do LCH4 and LOX for the return home.
Its about energy and if its not going to be anything but RTG and Solar we are going to think about how its best used.
kbd512 wrote:
The input energy requirement for LOX/LCO manufacture is around 110MJ/kg of payload delivered to LMO and LOX/LCH4 is 460MJ/kg of payload delivered to LMO.

kbd512 · 2020-01-02 21:02:20

Louis,

SpaceX's plan looks like at least as much nonsense as anything Lockheed has come up with. 500 tons of equipment is nothing magical. Here on Earth we routinely ship a lot more mud than that to drill the first section of a well. If we're talking total tonnage to drill a well a several miles deep, then the total tonnage of materials delivered to the rig is in the range of what one of our cruisers displaces. Other than saying, "then the mission will fail", you still haven't told me what happens to the crew if it does. Lockheed's plan addresses that, whereas SpaceX's plan doesn't. Maybe Congress, FAA, and NASA will let them experiment in that way with peoples' lives, but I kinda doubt it. Apart from that, you've made a lot more statements about your beliefs than verifiable facts.

SpaceNut · 2020-01-03 14:51:07

Part of the problem for mars is that for every 1kg of mass on the syrface of mars it takes 10kg on orbit to get it there.

louis · 2020-01-03 15:05:40

I have seen no proposals from Space X for drilling for water, so there's seem no point in mentioning it further in relation to Space X's first mission. Ice is reported to be just 30 cms, not even metres, below the surface at various point near the proposed landing sites, bordering Arcadia Planitia and Amazonis Planitia.

https://www.universetoday.com/144363/na … -a-shovel/

If the ice is just 30 cms below the surface, it should be easy to expose it with diggers, break it up with mechanical hammers and scoop it up in digger machine buckets. It can then be deposited in sealable tanks.

One always has to contemplate failure...a freak meteorite shower could always destroy the return Starship for instance.

All I would say is that we would ensure the crew had enough food and other essential supplies to allow them to survive until the next Mission arrived.

I don't really accept that water ice will not be located. But the option of processing regolith and possibly dehumidifying the atmosphere could be included in the mission architecture.

kbd512 wrote:

Louis,
SpaceX's plan looks like at least as much nonsense as anything Lockheed has come up with. 500 tons of equipment is nothing magical. Here on Earth we routinely ship a lot more mud than that to drill the first section of a well. If we're talking total tonnage to drill a well a several miles deep, then the total tonnage of materials delivered to the rig is in the range of what one of our cruisers displaces. Other than saying, "then the mission will fail", you still haven't told me what happens to the crew if it does. Lockheed's plan addresses that, whereas SpaceX's plan doesn't. Maybe Congress, FAA, and NASA will let them experiment in that way with peoples' lives, but I kinda doubt it. Apart from that, you've made a lot more statements about your beliefs than verifiable facts.

SpaceNut · 2020-01-03 17:01:44

That sounds like the ground water table frost line for winter here in NH and the ground is harder than hell during that time of year.

louis · 2020-01-03 18:08:41

Maybe a half scale version of this, at 5 tons, would be suitable for breaking ice on Mars:

https://www.youtube.com/watch?v=LtuhVqYys40

Or we might use some sort of laser system to soften and then dig out the ice. It takes quite a long time for ice to sublimate even in a total vacuum.

SpaceNut wrote:

That sounds like the ground water table frost line for winter here in NH and the ground is harder than hell during that time of year.

kbd512 · 2020-01-04 13:29:51

Louis,

The only people I see working on regolith mining technology and orbital propellant transfer are NASA's traditional contractors and employees. There's no reason I can think of as to why NASA wouldn't license the technology to SpaceX since NASA owns the patents, but SpaceX is relying on technological developments that are nowhere close to the finish line.

SpaceX has made everything they're doing very public in an attempt to garner investment and support for their activities, which they've received to a limited degree from a handful of interested parties. The one thing I don't see them working on is everything else required to make their plans work. Your assertions that it's a big secret runs directly counter to the behavior of all space contractors, as it pertains to every other aspect of the various mission proposals- it's all very public and regular press releases are provided. Patents are also routinely filed to protect intellectual property.

If NASA can confirm the availability of water resources ahead of time by taking a sample, perfect the required mining technologies, perfect the Sabatier reactor technology to operate at industrial scale, and develop all the ancillary technologies required to deliver to or transport around the surface of Mars, then I can see SpaceX's proposal becoming more viable. I don't see "all the stars aligning", so to speak, for at least another 10 years.

SpaceNut · 2020-01-04 15:06:26

The technology that you buy is the one you can not make for your self solved to on paper to build via the engineering that you pay for. The next is the technolgy product that can buy for the right cost to you which can be intergrated without change.
Building engineered product that infringes on patents are always a problem when building any technology.

louis · 2020-01-04 16:14:33

NASA held a competition for regolith-ice processing. Clearly it has received some attention.

I don't think anyone needs a patent for using a digger to break through maybe half a metre of regolith to get at ice.

"Your assertions that it's a big secret..."

Not sure what you are referring to. I haven't claimed anything is a "big secret". NASA has published their understanding of water-ice deposits on Mars and NASA people have spoken in public about that. The potential landing sites identified for Space X were not a public matter I think, but we know JPL were helping with that. The fact that the landing sites are within the area identified as having ice close to the surface is hardly a surprise.

kbd512 wrote:

Louis,
The only people I see working on regolith mining technology and orbital propellant transfer are NASA's traditional contractors and employees. There's no reason I can think of as to why NASA wouldn't license the technology to SpaceX since NASA owns the patents, but SpaceX is relying on technological developments that are nowhere close to the finish line.
SpaceX has made everything they're doing very public in an attempt to garner investment and support for their activities, which they've received to a limited degree from a handful of interested parties. The one thing I don't see them working on is everything else required to make their plans work. Your assertions that it's a big secret runs directly counter to the behavior of all space contractors, as it pertains to every other aspect of the various mission proposals- it's all very public and regular press releases are provided. Patents are also routinely filed to protect intellectual property.
If NASA can confirm the availability of water resources ahead of time by taking a sample, perfect the required mining technologies, perfect the Sabatier reactor technology to operate at industrial scale, and develop all the ancillary technologies required to deliver to or transport around the surface of Mars, then I can see SpaceX's proposal becoming more viable. I don't see "all the stars aligning", so to speak, for at least another 10 years.

Last edited by louis (2020-01-04 16:15:41)

New Mars Forums

Announcement

#26 2019-10-24 20:39:37

Re: Constructing a human mission, a tonne at a time

#27 2019-12-30 21:20:03

Re: Constructing a human mission, a tonne at a time

#28 2019-12-30 21:25:05

Re: Constructing a human mission, a tonne at a time

#29 2019-12-31 01:58:24

Re: Constructing a human mission, a tonne at a time

#30 2019-12-31 05:58:49

Re: Constructing a human mission, a tonne at a time

#31 2019-12-31 10:41:19

Re: Constructing a human mission, a tonne at a time

#32 2019-12-31 14:35:53

Re: Constructing a human mission, a tonne at a time

#33 2019-12-31 15:58:10

Re: Constructing a human mission, a tonne at a time

#34 2020-01-01 13:52:28

Re: Constructing a human mission, a tonne at a time

#35 2020-01-01 14:45:22

Re: Constructing a human mission, a tonne at a time

#36 2020-01-01 18:55:24

Re: Constructing a human mission, a tonne at a time

#37 2020-01-01 19:04:22

Re: Constructing a human mission, a tonne at a time

#38 2020-01-01 19:21:02

Re: Constructing a human mission, a tonne at a time

#39 2020-01-01 21:03:52

Re: Constructing a human mission, a tonne at a time

#40 2020-01-02 05:48:58

Re: Constructing a human mission, a tonne at a time

#41 2020-01-02 18:54:49

Re: Constructing a human mission, a tonne at a time

#42 2020-01-02 19:51:33

Re: Constructing a human mission, a tonne at a time

#43 2020-01-02 21:02:20

Re: Constructing a human mission, a tonne at a time

#44 2020-01-03 14:51:07

Re: Constructing a human mission, a tonne at a time

#45 2020-01-03 15:05:40

Re: Constructing a human mission, a tonne at a time

#46 2020-01-03 17:01:44

Re: Constructing a human mission, a tonne at a time

#47 2020-01-03 18:08:41

Re: Constructing a human mission, a tonne at a time

#48 2020-01-04 13:29:51

Re: Constructing a human mission, a tonne at a time

#49 2020-01-04 15:06:26

Re: Constructing a human mission, a tonne at a time

#50 2020-01-04 16:14:33

Re: Constructing a human mission, a tonne at a time

Board footer