Poll

So, anyone want to guess if Blue Origin will be ready for Artemis V?

Yeah, they'll build a robust lander with time to spare.
6 (20%)
They will need many waivers for non-conforming hardware, but they'll make it.
3 (10%)
They will delay Artemis V by some noticeable time span, but eventually they will make it.
13 (43.3%)
SpaceX will have to provide hardware for Artemis V.
8 (26.7%)
Other (please specify)
0 (0%)

Total Members Voted: 30

Voting closed: 06/01/2023 07:41 pm


Author Topic: Starship Artemis Contract & Lunar Starship  (Read 1064164 times)

Offline TomH

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Re: Starship Artemis Contract & Lunar Starship
« Reply #2840 on: 12/20/2023 07:25 am »
you may hate blue origin, but starship with 15+ tankers to send one starship to the moon is unfortunatelly ridiculous, those "green" activists may have an actual argument this time, that many launches of the worlds biggest rocket in short time from one place may actually cause non negligible impact on the environment

Multiple flights of Starship, most of which may involve fully reusable vehicles, is still far less expensive than 4 launches of vehicles that are primarily disposable. And if you can replace SLS with a partly reusable SH/SS, it becomes even less costly. What are the public and congress going to care about more, number of flights, or the final price tag?

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Re: Starship Artemis Contract & Lunar Starship
« Reply #2841 on: 12/20/2023 12:03 pm »


Multiple flights of Starship, most of which may involve fully reusable vehicles, is still far less expensive than 4 launches of vehicles that are primarily disposable.

That remains to be seen. I'm pretty sure you could get rid of the "far" at any rate.

Offline OTV Booster

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Re: Starship Artemis Contract & Lunar Starship
« Reply #2842 on: 12/20/2023 06:12 pm »
you may hate blue origin, but starship with 15+ tankers to send one starship to the moon is unfortunatelly ridiculous, those "green" activists may have an actual argument this time, that many launches of the worlds biggest rocket in short time from one place may actually cause non negligible impact on the environment

Multiple flights of Starship, most of which may involve fully reusable vehicles, is still far less expensive than 4 launches of vehicles that are primarily disposable. And if you can replace SLS with a partly reusable SH/SS, it becomes even less costly. What are the public and congress going to care about more, number of flights, or the final price tag?
Depends on who you ask. We're part of the public and we worry about the number of flights. We worry about cost primarily because higher cost = fewer flights, with some secondary reasons.


TAHOTS (The Average Human On The Street) gets excited/entertained by launches and pretty pictures within a standard distribution curve and otherwise is uninterested but supports anything that might lower taxes - as long as it won't kill their job.


Congress critters? Another standard distribution curve skewed by perceived self interest. Elected officials have an overinflated concept of self interest.
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Offline clongton

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Re: Starship Artemis Contract & Lunar Starship
« Reply #2843 on: 12/21/2023 01:17 am »
Some of the soil on the moon is 40% oxygen.  So oxygen could be extracted on the moon, liquified, and with low gravity launched to lunar orbit and back to LEO for refueling. 

This provides an opportunity to let the moon share the burden of the earth/moon transportation system; not by transporting LOX to LEO, but by refueling the lunar shuttle with Lunar LOX in lunar orbit. The shuttle (in this case a Starship), would receive a full load of CH4 in LEO, with only 1/2 of a LOX load and then proceed to the moon. Upon arriving in lunar orbit it would have depleted its remaining LOX load but still have 1/2 its CH4. The shuttle would refill its LOX tank with lunar LOX and depart for LEO, arriving there with having depleted its remaining CH4 but still have 1/2 its LOX. In LEO it refills the CH4 tank and departs for  the moon with its LOX tank 1/2 full of lunar LOX. Rinse/repeat. This sharing of propellant SOURCE between the 2 celestial bodies will allow increased payload capacity with reduced cost - both ways.

Figuring out how to do this should be a project of prime importance for the Artemis program.
« Last Edit: 12/21/2023 01:32 am by clongton »
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Offline rsdavis9

Re: Starship Artemis Contract & Lunar Starship
« Reply #2844 on: 12/21/2023 12:47 pm »
Some of the soil on the moon is 40% oxygen.  So oxygen could be extracted on the moon, liquified, and with low gravity launched to lunar orbit and back to LEO for refueling. 

This provides an opportunity to let the moon share the burden of the earth/moon transportation system; not by transporting LOX to LEO, but by refueling the lunar shuttle with Lunar LOX in lunar orbit. The shuttle (in this case a Starship), would receive a full load of CH4 in LEO, with only 1/2 of a LOX load and then proceed to the moon. Upon arriving in lunar orbit it would have depleted its remaining LOX load but still have 1/2 its CH4. The shuttle would refill its LOX tank with lunar LOX and depart for LEO, arriving there with having depleted its remaining CH4 but still have 1/2 its LOX. In LEO it refills the CH4 tank and departs for  the moon with its LOX tank 1/2 full of lunar LOX. Rinse/repeat. This sharing of propellant SOURCE between the 2 celestial bodies will allow increased payload capacity with reduced cost - both ways.

Figuring out how to do this should be a project of prime importance for the Artemis program.

Has anybody done the basic energy calc?
The added energy of taking 1kg from earth's surface to moon orbit.
The energy require to separate oxygen from rock. We could probably use aluminum production on earth to get an estimate. Take bauxite(Al2O3) dissolve in molten cryolite, apply electricity and we get O2 and Al.
 

EDIT:

I get 62 MJ/kg for raising 1 kg from earths surface to moon orbital distance.
em*G/er - em*G/moondist     # em=earth mass er=earth radius moondist=moon distance from earth.

https://en.wikipedia.org/wiki/Aluminium#Production_and_refinement
says
"Aluminium production is highly energy-consuming, and so the producers tend to locate smelters in places where electric power is both plentiful and inexpensive.[132] Production of one kilogram of aluminium requires 7 kilograms of oil energy equivalent, as compared to 1.5 kilograms for steel and 2 kilograms for plastic.[133]"

So we have 1kg of oil = 42MJ
7 * 42MJ = 294MJ/kg

and aluminum and oxygen is roughly the same in Al2O3
294/62 = 4.7
So 5 times as much energy to make oxygen versus shipping it.

« Last Edit: 12/21/2023 01:32 pm by rsdavis9 »
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Online TheRadicalModerate

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Re: Starship Artemis Contract & Lunar Starship
« Reply #2845 on: 12/21/2023 10:24 pm »
Some of the soil on the moon is 40% oxygen.  So oxygen could be extracted on the moon, liquified, and with low gravity launched to lunar orbit and back to LEO for refueling. 

This provides an opportunity to let the moon share the burden of the earth/moon transportation system; not by transporting LOX to LEO, but by refueling the lunar shuttle with Lunar LOX in lunar orbit. The shuttle (in this case a Starship), would receive a full load of CH4 in LEO, with only 1/2 of a LOX load and then proceed to the moon. Upon arriving in lunar orbit it would have depleted its remaining LOX load but still have 1/2 its CH4. The shuttle would refill its LOX tank with lunar LOX and depart for LEO, arriving there with having depleted its remaining CH4 but still have 1/2 its LOX. In LEO it refills the CH4 tank and departs for  the moon with its LOX tank 1/2 full of lunar LOX. Rinse/repeat. This sharing of propellant SOURCE between the 2 celestial bodies will allow increased payload capacity with reduced cost - both ways.

Figuring out how to do this should be a project of prime importance for the Artemis program.

I would like to see Artemis invest in some pilot projects for stuff like this, but at best, they're going to have access to 10kWe Kilopower nukes or solar panels with intermittent power (not a great thing for continuous chemical processes).

The LUNOX studies in the early 90's estimated you'd need 3MWe of continuous power to produce 1000t/year of LOX.  (Handy graphs in Fig. 1-2 from this LANTR paper from 1997.)     Even if you dedicate 10 Kilopowers to LUNOX (no clue what they'll cost), at that scaling, you're looking at only 33t of LOX per year.  I can think of some pretty useful things to do with 33t of LOX each year, but refueling a Starship isn't one of them.
« Last Edit: 12/21/2023 10:26 pm by TheRadicalModerate »

Offline Zed_Noir

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Re: Starship Artemis Contract & Lunar Starship
« Reply #2846 on: 12/21/2023 11:51 pm »
<snip>
I would like to see Artemis invest in some pilot projects for stuff like this, but at best, they're going to have access to 10kWe Kilopower nukes or solar panels with intermittent power (not a great thing for continuous chemical processes).
<snip>
For intermittent solar power issues. Nothing that a few Starships stuffed with storage batteries couldn't solved. Was that a maximum of 150 or more tonnes of payload for a Starship on one way mission to the Lunar surface?
« Last Edit: 12/22/2023 11:11 am by Zed_Noir »

Offline Lee Jay

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Re: Starship Artemis Contract & Lunar Starship
« Reply #2847 on: 12/22/2023 12:46 am »
For intermittent solar power issues. Nothing that a few Starships stuffed with storage batteries couldn't solved. Was that a maximum of 150 or more tonnes of payload for a Starship on one way mission to the Lunar surface?

Batteries that can keep themselves thermally regulated on the moon are going to have a lot more ancillary equipment and vampire energy draw than similar batteries on Earth. Especially with two week long day and night periods. Not trivial for tens of MWH.
« Last Edit: 12/22/2023 09:17 pm by Lee Jay »

Offline Brigantine

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Re: Starship Artemis Contract & Lunar Starship
« Reply #2848 on: 12/22/2023 01:13 am »
Out of curiosity, I looked at how to get permanent sunlight on the moon

1.53⁰ axial tilt (relative to ecliptic), 1736 km radius, if you assume a spherical moon with no terrain, your solar array at the N/S pole would need to be mounted 620m high in order to see (the center of) the sun all day long even in winter. ~280m if you just needed to never quite have a complete sunset (can't help eclipses)

Not sure if actual terrain works to help or hinder this. Or even if it would be close to any oxygen ore.

Conclusion: it's still beyond the scope of Artemis. Just go to the summer pole for a few months.

Online Robotbeat

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Re: Starship Artemis Contract & Lunar Starship
« Reply #2849 on: 12/22/2023 01:25 am »
Fix your quotes, everyone! Lee Jay and Zed.
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Re: Starship Artemis Contract & Lunar Starship
« Reply #2850 on: 12/22/2023 01:34 am »
Out of curiosity, I looked at how to get permanent sunlight on the moon

1.53⁰ axial tilt (relative to ecliptic), 1736 km radius, if you assume a spherical moon with no terrain, your solar array at the N/S pole would need to be mounted 620m high in order to see (the center of) the sun all day long even in winter. ~280m if you just needed to never quite have a complete sunset (can't help eclipses)

Not sure if actual terrain works to help or hinder this. Or even if it would be close to any oxygen ore.

Conclusion: it's still beyond the scope of Artemis. Just go to the summer pole for a few months.
NASA Langley has been developing and testing a Tall Lunar Tower prototype just for this purpose. Here's a short presentation of the work Iok Wong and others have done developing it:  (you can find more by searching "Tall Lunar Tower" on ntrs.nasa.gov)
Chris  Whoever loves correction loves knowledge, but he who hates reproof is stupid.

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Offline catdlr

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Re: Starship Artemis Contract & Lunar Starship
« Reply #2851 on: 12/22/2023 02:02 am »
Fix your quotes, everyone!

If people are having issues with quotes, use the preview button to see how the post will appear. Correct the pairs of quotes correctly, just count pair groupings making sure each ending quote matches a starting quote. The post should occur after the last quote pair.
« Last Edit: 12/22/2023 02:04 am by catdlr »
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Offline Asteroza

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Re: Starship Artemis Contract & Lunar Starship
« Reply #2852 on: 12/22/2023 04:41 am »
Out of curiosity, I looked at how to get permanent sunlight on the moon

1.53⁰ axial tilt (relative to ecliptic), 1736 km radius, if you assume a spherical moon with no terrain, your solar array at the N/S pole would need to be mounted 620m high in order to see (the center of) the sun all day long even in winter. ~280m if you just needed to never quite have a complete sunset (can't help eclipses)

Not sure if actual terrain works to help or hinder this. Or even if it would be close to any oxygen ore.

Conclusion: it's still beyond the scope of Artemis. Just go to the summer pole for a few months.
NASA Langley has been developing and testing a Tall Lunar Tower prototype just for this purpose. Here's a short presentation of the work Iok Wong and others have done developing it:  (you can find more by searching "Tall Lunar Tower" on ntrs.nasa.gov)

File name suggests Lunar Surface Innovation Consortium (LSIC)

https://lsic.jhuapl.edu/Our-Work/Focus-Areas/index.php?fg=Surface-Power

which is related to the DARPA LOGIC group working on lunar infrastructure standards

https://logic.jhuapl.edu/

Online FutureSpaceTourist

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Re: Starship Artemis Contract & Lunar Starship
« Reply #2853 on: 12/22/2023 05:57 am »
https://twitter.com/nasa_marshall/status/1737956115910955290

Quote
Going up 🔺

@NASAAstronauts Nicole Mann and Doug “Wheels” Wheelock participated in a recent test of a sub-scale mockup elevator for SpaceX’s Starship human landing system that will be used for NASA’s #Artemis III and IV missions to the Moon.

READ MORE >>

https://www.nasa.gov/image-article/nasa-astronauts-test-spacex-elevator-concept-for-artemis-lunar-lander/

Quote
NASA Astronauts Test SpaceX Elevator Concept for Artemis Lunar Lander

Lee Mohon
DEC 21, 2023
ARTICLE

NASA astronauts Nicole Mann and Doug “Wheels” Wheelock participated in a recent test of a sub-scale mockup elevator for SpaceX’s Starship human landing system that will be used for NASA’s Artemis III and IV missions to the Moon. The Starship human landing system will carry two astronauts from the Orion spacecraft in lunar orbit to the surface, serve as a habitat for crew members’ approximately one week stay on the Moon, and transfer them from the surface back to Orion.

The elevator will transport equipment and crew between Starship’s habitable area, located near the top of the lander, and the lunar surface, as they exit for moonwalks. The test allowed the astronauts to interact with a flight-like design of the elevator system, serving as both a functional demonstration of the hardware and providing the chance to receive valuable feedback from a crew perspective.

Built at SpaceX’s facility in Hawthorne, California, the elevator mockup has a full-scale basket section with functioning mechanical assemblies and crew interfaces for testing. During the demonstration, NASA astronauts wore spacesuits that simulate the suit size and mobility constraints that crew will face on the Moon. For Artemis III, the crew will wear new advanced spacesuits being developed by Axiom Space.

The suited crew provided feedback on elevator controls, such as gate latches, ramp deployment interfaces for moving into and out of the elevator basket, available space for cargo, and dynamic operations while the basket moved along a vertical rail system.

NASA is working to land the first woman and first person of color on the Moon under Artemis to explore more of the lunar surface than ever before and prepare to send humans to Mars for the benefit of all. The human landing system is a critical piece of deep space exploration architecture, along with the Space Launch System rocket, Orion spacecraft, advanced spacesuits and rovers, and the Gateway in orbit around the Moon.

Read more about Artemis:

https://www.nasa.gov/humans-in-space/artemis
« Last Edit: 12/22/2023 05:59 am by FutureSpaceTourist »

Offline Slarty1080

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Re: Starship Artemis Contract & Lunar Starship
« Reply #2854 on: 12/22/2023 05:23 pm »
you may hate blue origin, but starship with 15+ tankers to send one starship to the moon is unfortunatelly ridiculous, those "green" activists may have an actual argument this time, that many launches of the worlds biggest rocket in short time from one place may actually cause non negligible impact on the environment

Multiple flights of Starship, most of which may involve fully reusable vehicles, is still far less expensive than 4 launches of vehicles that are primarily disposable. And if you can replace SLS with a partly reusable SH/SS, it becomes even less costly. What are the public and congress going to care about more, number of flights, or the final price tag?

"and you can replace SLS with a partly reusable SH/SS" except that the critters in Congress won't like that one little bit. The reason being that they don't give a damn about space. They don't care what flies, when it flies or even if it flies. All they care about is votes, thousands of high tech well paid jobs in key states and a few opportunities to grandstand. Cancelling SLS will be as popular in Congress as a hot bucket of sand in the face. Eventually they will be forced to accept the inevitable, but that may take a long time.
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Offline KilroySmith

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Re: Starship Artemis Contract & Lunar Starship
« Reply #2855 on: 12/22/2023 05:54 pm »

Quote
Going up 🔺

@NASAAstronauts Nicole Mann and Doug “Wheels” Wheelock participated in a recent test of a sub-scale mockup elevator for SpaceX’s Starship human landing system that will be used for NASA’s #Artemis III and IV missions to the Moon.


Sub-scale?  Just how big IS this thing  :o?

Offline DanClemmensen

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Re: Starship Artemis Contract & Lunar Starship
« Reply #2856 on: 12/22/2023 06:04 pm »
you may hate blue origin, but starship with 15+ tankers to send one starship to the moon is unfortunatelly ridiculous, those "green" activists may have an actual argument this time, that many launches of the worlds biggest rocket in short time from one place may actually cause non negligible impact on the environment

Multiple flights of Starship, most of which may involve fully reusable vehicles, is still far less expensive than 4 launches of vehicles that are primarily disposable. And if you can replace SLS with a partly reusable SH/SS, it becomes even less costly. What are the public and congress going to care about more, number of flights, or the final price tag?

"and you can replace SLS with a partly reusable SH/SS" except that the critters in Congress won't like that one little bit. The reason being that they don't give a damn about space. They don't care what flies, when it flies or even if it flies. All they care about is votes, thousands of high tech well paid jobs in key states and a few opportunities to grandstand. Cancelling SLS will be as popular in Congress as a hot bucket of sand in the face. Eventually they will be forced to accept the inevitable, but that may take a long time.
"Oh no, senator, we will not replace SLS/Orion. We will continue to fly the main Artemis missions using SLS/Orion at the same proposed pace. We will increase the effectiveness of Artemis (and SLS/Orion) by adding additional missions using alternate hardware, which also provides a backup in case anything bad happens."
Now if we can only find some senior NASA folks who can say this with a straight face.

Offline DanClemmensen

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Re: Starship Artemis Contract & Lunar Starship
« Reply #2857 on: 12/22/2023 06:18 pm »

Quote
Going up 🔺

@NASAAstronauts Nicole Mann and Doug “Wheels” Wheelock participated in a recent test of a sub-scale mockup elevator for SpaceX’s Starship human landing system that will be used for NASA’s #Artemis III and IV missions to the Moon.


Sub-scale?  Just how big IS this thing  :o?
The document says it's a "full-scale basket", so I assume the "sub-scale" refers to the height from the pulley to the ground.
« Last Edit: 12/22/2023 06:19 pm by DanClemmensen »

Offline OTV Booster

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Re: Starship Artemis Contract & Lunar Starship
« Reply #2858 on: 12/22/2023 06:47 pm »
you may hate blue origin, but starship with 15+ tankers to send one starship to the moon is unfortunatelly ridiculous, those "green" activists may have an actual argument this time, that many launches of the worlds biggest rocket in short time from one place may actually cause non negligible impact on the environment

Multiple flights of Starship, most of which may involve fully reusable vehicles, is still far less expensive than 4 launches of vehicles that are primarily disposable. And if you can replace SLS with a partly reusable SH/SS, it becomes even less costly. What are the public and congress going to care about more, number of flights, or the final price tag?

"and you can replace SLS with a partly reusable SH/SS" except that the critters in Congress won't like that one little bit. The reason being that they don't give a damn about space. They don't care what flies, when it flies or even if it flies. All they care about is votes, thousands of high tech well paid jobs in key states and a few opportunities to grandstand. Cancelling SLS will be as popular in Congress as a hot bucket of sand in the face. Eventually they will be forced to accept the inevitable, but that may take a long time.
Naw, I'd give it 3-4 crewed flights. Once LSS shows it can do the job and do it for a lot less, there will be pressure within congress to kill SLS. For now, LSS is unproven. Give it time.


Stop an think. OMB is rumbling and not all seats at the trough are the same. The Congress critters that get meager servings have their own concerns and need budget money to satisfy them. Admittedly, the committee process makes some more powerful than others but that's only one part of the total messy process.


Come election time, an insurgent within a party or an opponent from outside the party (plug in republican or democrat as you see fit) that makes killing an overpriced white elephant that has an economical alternative a campaign issue, the obituary is half written. Find a way to soften the burden on the SLS tech workers and it's almost a done deal.


The chance of Artemus being cancelled outright are slim as long as the US sees itself as being in competition with China.
We are on the cusp of revolutionary access to space. One hallmark of a revolution is that there is a disjuncture through which projections do not work. The thread must be picked up anew and the tapestry of history woven with a fresh pattern.

Offline spacenut

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Re: Starship Artemis Contract & Lunar Starship
« Reply #2859 on: 12/22/2023 09:05 pm »
From what I have read, oxygen can be extracted from lunar sand, using solar power.  It may take a longer than transporting it, but 14 days out of the month oxygen can be extracted.  This can be used for lox for rockets and breathing.  Hydrogen brought from earth, which is much lighter to transport using less fuel, can be used for rocket fuel and making water for use on the moon. 

Heck, a Starship could refuel it's lox supply for landing back on earth by bringing more methane from earth.  Methane is also lighter than lox for transporting.  Just change a lunar Starships tankage a bit.  Use only for earth-lunar transport, or L1 station back to earth.  There are ways to cut refueling launches needed for lunar or Mars expeditions, using lunar lox at L1 or L2 on the way to and from Mars.  Lunar lox can become a valuable commodity.   

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