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Artemis 3 Mission in 2024
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Artemis 3 Mission in 2024
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Artemis 3 Mission in 2024
On 19-08-04 17:53 , Jeff Findley wrote:
In article , says... On 2019-08-03 12:54, Jeff Findley wrote: ... Even Musk's plan to use Starship to go to Mars will take a *lot* of tanker Starship flights to LEO just to bring up enough propellant for LEO is the keyword here. not "Gateway". LEO lets you deliver fuel much faster, and with far less hot re-entry than coming back from Gateway. The Starship tankers won't need to be able to handle a reentry from a return from the moon and/or Mars. So their thermal protection system might not need to be quite as complex/expensive. But, the crewed Starships going to the moon and/or Mars will need to be able to handle that. A fall-back alternative might be for a Starship, returning to Earth from Mars, to use its remaining fuel not for landing, but to brake into a low orbit around Earth. A tanker could then refuel the Starship with enough fuel for reentry and landing on Earth. However, braking into LEO from a Mars-return trajectoy may need considerably more fuel than a mere landing on Earth after an aerobraking re-entry, so this fall-back method would probably reduce payload capacity; the question is by how much, and I suspect by a lot. This could perhaps be solved by refueling the returning Starship in low Mars orbit, after launch from Mars and before trans-Earth injection, using tankers (or Starships acting as tankers) from Mars, but that is getting a bit complex... -- Niklas Holsti Tidorum Ltd niklas holsti tidorum fi . @ . |
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Artemis 3 Mission in 2024
In article ,
says... On 2019-08-04 10:53, Jeff Findley wrote: Again, I disagree completely. Zero work at NASA is happening to send people to Mars. However, NASA is actively working on both Gateway and on procuring crewed lunar landers for a lunar mission. Is there a budget for gateway? Yes. NASA has already issued a contract for the first module. Cite: NASA Awards Artemis Contract for Lunar Gateway Power, Propulsion May 23, 2019 - RELEASE 19-042 https://www.nasa.gov/press-release/n...-contract-for- lunar-gateway-power-propulsion Is there a budget for a lander? For crewed landers, that remains to be seen, but NASA has already issued contracts for the precursor uncrewed landers. Cite: NASA picks three companies to send commercial landers to the moon June 4, - 2019 Stephen Clark https://spaceflightnow.com/2019/06/0...-companies-to- send-commercial-landers-to-the-moon/ One of the contractors backed out, so there are now two active contractors for this part of the return to the moon. Cite: NASA terminates lunar lander contract with OrbitBeyond July 30, 2019 - Stephen Clark https://spaceflightnow.com/2019/07/3...-lunar-lander- contract-with-orbitbeyond/ If it is all at the "thinking about concepts" stage, isn't that too different than thinking about concepts to Mars? Yes, because NASA is actively working on contracts and funding for sending crew to the moon. They are *not* doing that for Mars. They're paying lip-service to Mars (i.e. spin by the marketing people). Part of this is the typical HLV type justification for SLS, whose role in the crewed return to the moon has already been minimized to simply launching Orion. Commercial partnerships are being forged to build and launch Gateway as well as uncrewed and crewed landers. So, the SLS folks are getting justifiably worried that they simply aren't needed anymore (they're not). Here's a cite that includes a "time-line" for Artemis. Note that all the crewed flights "planned" are to the moon. The notional "to Mars" mission isn't until the 2030s. Cite: NASA - Explore Moon to Mars https://www.nasa.gov/specials/moon2mars/ If a politician has stated that we should go to the Moon by 2024, but budgets have not been allocacated for more than the on-going SLS work, can NASA really actively woirk on landing on moon? pay to have suits developped beyond marketing prototype ? No bucks, no Buck Rogers. But do note that applies to Mars too. Money has been allocated to start building Gateway (i.e. moon). Absolutely zero has been allocated towards any crewed Mars mission. Again, this Administration's actions speak louder than Trump's words when it comes to NASA. Mars simply isn't a priority outside of Trump's word salad he spewed during the 50th anniversary of Apollo 11. While I agree that NASA has changed fron advertising SLS/Orion as being part of a plan to go to Mars to being part of a plan to get to the Moon, and the branding has changedf to Artemis to further focus on Moon, having a tight deadline without additional budgets seems to point to politicial PR speak without NASA having the means to actually get it done. Exactly. It's all marketing branding in an attempt to make Artemis look bigger than it really is. Nothing about Artemis would help send crew to Mars. Everything about Mars is different than the moon, so the solutions to get there, land there, make propellant there, perform EVAs there, and get back to earth are *all* different. Things that are different just aren't the same. This whole "moon to Mars" is simply marketing bull****, IMHO. The evidence is in where the money is being spent (and where it is not being spent). What Artemis does is make it more politically acceptable to keep dumping money into SLS by painting SLS as key part of some (virtual) plan to get to the Moon, knowing full well that SLS will be canned at an opportune time. And to me, opportune time is after SLS has done its test flights and does a final spin around the Moon with someone in it. Exactly. It's an act of desperation to justify SLS, even though the only payload designed to be launched on SLS is Orion. Well and possibly the Congressionally mandated Europa probe. Cite: Europa or Enceladus? If NASA switches from SLS to Falcon Heavy, it won't have to choose - by Mark Whittington ? October 10, 2018 https://spacenews.com/europa-or-ence...s-from-sls-to- falcon-heavy-it-wont-have-to-choose/ In terms of the lander, how does this work? Does NASA decide on the concept and overall design, and then ask for bids to exceute this? or does it just ask for bid for *any* design for a Mars Landder giving only "must fit within X kg mass and such and such size requirements" ? They're seeking proposals from contractors. It remains to be seen what the contracts will look like. But given what I've read about NASA Administrator Bridenstine, the contracts are far more likely to be a public/private partnership or a "commercial" contract than they are to be "cost-plus" contracts. And at what point would NASA have to go to RFP and decide on a contractor? Is it allowed to do this if no budget has been set for this? Ultimately, Congress has to allocate funds to pay the bills. If NASA were to go to RFP today and gets answers tomorrow, can it go to COngress next week and says "landing on moon will cost $X" and get that budget allocated? (akaL money shifted around) or must it wait full budget cycle to get approval? You really need to read up on the current news. Cite: NASA?s Budget Gets a Boost for the Artemis Moon Initiative By: David Dickinson - May 22, 2019 https://www.skyandtelescope.com/astr...-budget-boost- artemis-moon-initiative/ NASA administrator says it will cost an extra $20 to $30 billion to send astronauts back to the Moon - Jim Bridenstine finally dished on the details - By Loren Grush @lorengrush - Jun 14, 2019, 8:11am EDT https://www.theverge.com/2019/6/14/1...rator-artemis- moon-return-cost-estimate-20-30-billion-dollars-bridenstine Wishful thinking. Since we're spouting wild-assed guesses, at this point I think SLS has the political inertia to fly at least three or four times. The have enough SSMEs for that. But how many centre stages and SRBs have been built? One core stage has been built. As for SRB case segments, Google is your friend: SLS requires Advanced Boosters by flight nine due to lack of Shuttle heritage components - by Chris Bergin May 8, 2018 https://www.nasaspaceflight.com/2018...osters-flight- nine-shuttle-heritage/ After that, NASA would presumably be paying for "advanced boosters" for SLS Block 2. Likely based on the composite wound (expendable) booster casings that Northrup Grumman Innovation Systems has developed for OmegA. Make no mistake, Starship isn't even a sure thing. Which is why there is *some* logic in continuing SLS/Orion in case SpaceX doesn't deliver, so NASA still has something, anything to play with in space. IMHO, there is no logic in continuing with SLS. We'd be far better off adapting Artemis to use existing launch vehicles. If they're good enough for DOD, they're good enough for NASA. And considering DOD always wants two providers, NASA gets two "certified" providers too. Jeff -- All opinions posted by me on Usenet News are mine, and mine alone. These posts do not reflect the opinions of my family, friends, employer, or any organization that I am a member of. |
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Artemis 3 Mission in 2024
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Artemis 3 Mission in 2024
On Saturday, August 3, 2019 at 12:43:23 PM UTC-4, Jeff Findley wrote:
says... If Moon manned landing missions were resumed, what would be a realistic schedule? Apollo flew about 3 times per year, and had massive amounts of funding. Given future funding, maybe one per year going forward? One every two years? That would be a lot slower than Apollo, but still having five missions per decade will do a lot of science over time, that would be 10 missions over the next 20 years. Plus doing things not done by Apollo, such as the mission the south polar area, missions to the far side of the Moon, missions to mountainous areas, etc. If Congress continues to fund SLS/Orion ($2+ billion a year just for SLS), then the flight rate will be at most twice per year. At first, it will be only once a year, once crew is flying, IMHO. Boeing is having a hard time building the SLS core stage. And while they claim they've discovered ways to make that go faster, I'll take that claim with a grain of salt until they prove they can ramp up the flight rate to something "reasonable", which is 2x a year for SLS. In reality, 2x a year is a pathetic flight rate and worse than Apollo did 50+ years ago. We have had zero a year for the last 50 years. Wouldn't 20 per decade be an enormous improvement over that? Plus the sustainability to continue that for 2 or 3 decades or more? |
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Artemis 3 Mission in 2024
"Scott Kozel" wrote in message
... On Saturday, August 3, 2019 at 12:43:23 PM UTC-4, Jeff Findley wrote: says... If Moon manned landing missions were resumed, what would be a realistic schedule? Apollo flew about 3 times per year, and had massive amounts of funding. Given future funding, maybe one per year going forward? One every two years? That would be a lot slower than Apollo, but still having five missions per decade will do a lot of science over time, that would be 10 missions over the next 20 years. Plus doing things not done by Apollo, such as the mission the south polar area, missions to the far side of the Moon, missions to mountainous areas, etc. If Congress continues to fund SLS/Orion ($2+ billion a year just for SLS), then the flight rate will be at most twice per year. At first, it will be only once a year, once crew is flying, IMHO. Boeing is having a hard time building the SLS core stage. And while they claim they've discovered ways to make that go faster, I'll take that claim with a grain of salt until they prove they can ramp up the flight rate to something "reasonable", which is 2x a year for SLS. In reality, 2x a year is a pathetic flight rate and worse than Apollo did 50+ years ago. We have had zero a year for the last 50 years. Wouldn't 20 per decade be an enormous improvement over that? That assumes there's more than 2-3 flights... total. I just don't see SLS being sustainable at its price, especially with Falcon Heavy flying and BFR possibly coming along sooner than SLS. Plus the sustainability to continue that for 2 or 3 decades or more? At that cost, it's not sustainable. And keep in mind right now the first few SLS flights will be flying re-vamped SSMEs. Once those run out, we need new ones. -- Greg D. Moore http://greenmountainsoftware.wordpress.com/ CEO QuiCR: Quick, Crowdsourced Responses. http://www.quicr.net IT Disaster Response - https://www.amazon.com/Disaster-Resp...dp/1484221834/ |
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Artemis 3 Mission in 2024
Tsk tsk tsk.
Pages on pages of warbling about an imagined "lack of progress" shows that not one of you has bothered to do some cursory research on this subject. The suits are being built under the xEMU program, scheduled for a demonstration flight on the ISS within the next few years and demonstrated.[1] They have been under development for several years now. All components of the SLS supply chain have been or are in the process of being contracted for roughly a decade of flights.[2] Replacements for Shuttle-era equipment have been under development for several years now, and will be phased-in as the left-over stock is depleted.[2] The SSME replacements (the RS-25E) are being designed to utilize more efficient manufacturing techniques to reduce cost,[3] and the SRB replacements (BOLE) are being designed using common technology with Northrop Grumman's upcoming OmegA launch vehicle, including new lightweight composite SRB casings.[4] It's kind of baffling that [1] https://www.youtube.com/watch?v=4QVeNY4HdNM [2] https://www.reddit.com/r/SpaceLaunch...ls_production/ (easier to link this than link each individually) [3] https://www.nasaspaceflight.com/2018...ine-rs-25-run/ [4] https://ntrs.nasa.gov/archive/nasa/c...0190002126.pdf |
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Artemis 3 Mission in 2024
On Tuesday, March 3, 2020 at 1:38:30 PM UTC-6, wrote:
Tsk tsk tsk. Pages on pages of warbling about an imagined "lack of progress" shows that not one of you has bothered to do some cursory research on this subject. The suits are being built under the xEMU program, scheduled for a demonstration flight on the ISS within the next few years and demonstrated.[1] They have been under development for several years now. All components of the SLS supply chain have been or are in the process of being contracted for roughly a decade of flights.[2] Replacements for Shuttle-era equipment have been under development for several years now, and will be phased-in as the left-over stock is depleted.[2] The SSME replacements (the RS-25E) are being designed to utilize more efficient manufacturing techniques to reduce cost,[3] and the SRB replacements (BOLE) are being designed using common technology with Northrop Grumman's upcoming OmegA launch vehicle, including new lightweight composite SRB casings.[4] It's kind of baffling that [1] https://www.youtube.com/watch?v=4QVeNY4HdNM [2] https://www.reddit.com/r/SpaceLaunch...ls_production/ (easier to link this than link each individually) [3] https://www.nasaspaceflight.com/2018...ine-rs-25-run/ [4] https://ntrs.nasa.gov/archive/nasa/c...0190002126.pdf Accidentally hit post too early. Was going to cap it off by saying, "It's kind of baffling that these misconceptions went uncorrected for so long." |
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