very interesting seeing Will Patton cast
Musk, he said in our real world he is committed to Mars, 1 year to go for human supporting 'cargo'
The Ego gets a massage
Elon Musk treated like a rock star during China trip: ‘He’s a global idol’
https://nypost.com/2023/05/31/elon-musk … obal-idol/
Billionaire Elon Musk was showered with praise during a trip to China this week, with people on social media calling him “a pioneer,” “Brother Ma” and “a global idol”
There is a difference between the Utopia outlook of Jetsons and StarTrek and Dystopia of Robocop, BladeRunner, Silo, Terminator...if there is a simple difference to be explained to someone who has never experience scifi then I feel maybe its glass half full, half empty, one inspires by looking outward the other exploits the darker part of humanity and looks inward.
In scifi some newmars users and I personally have posted how I think S.Korea maybe culturally moved ahead of hollywood on fringe fantasy science fiction ideas, Hollywood used to inspire but maybe not so much these days and 'Twitter' the social media giant and social networking service owned and now operated by American company X Corp now offering hour long videos
https://twitter.com/elonmusk/status/1673831774038949888
I had read some of 'Silo' the science fiction dystopian, Hugh Howey did 'Wool' as a stand alone short story as first, many, many books I feel they read ok, he is a skilled writer but put I personally the books down, maybe it was too dark for my personal tastes.
I have tried reading many books, some series I left unfinished.
Elon Musk has an interesting journey, in his life story part of his geographical trip he moved from S.Africa to America and becomes an industry leader in the United States of America, in mid-2015, 'Silo' writer Howey went the other way and gave up his home in Florida, and moved to St Francis Bay, Eastern Cape, South Africa, these books were not 'bad' in fact they are good but not to my personal taste.
Sport Arena?
'a terrible idea'
https://www.theregister.com/2023/06/29/ … ied_fight/
on twitter
'entire first episode.'
maybe entire movies and shows have been posted on twitter, this is the first time I am aware of its potential as a media source.
48.7 M Views
Elon Musk himself as a media brand is easily one of the Most-followed accounts outside of super-Celebrity and Sports Star and Musicians who can rank ahead of Musk on followings, his name as a 'brand' is not number 1, for example Sony Entertainment Television India or Ariana Grande or 'PewDiePie' might pop up as a suggestion in vid internet feed more than 'Musk'
My personal reaction I think it is
Very interesting to see what scifi Elon Musk shared
Recently, in this topic or another, there was discussion of options for SpaceX Starship missions to Mars ...
Your post here triggered a thought that might encourage someone to evaluate it for feasibility ...
On Earth, it has been practice for many decades, to attach auxiliary fuel tanks to existing vehicles to extend their range.
I have suggested (perhaps in another topic) that it would make sense to give a fully fueled Starship a push from Earth LEO, so it does not have to use any of it's own fuel to depart Earth.
However, that idea has the disadvantage that the pusher vehicle has to have enough fuel and oxidizer on board to be able to return to LEO.
That is certainly practical, as the Falcon 9 has proved.
However, there ** is ** the alternative of attaching extra fuel and oxidizer tanks to the Starship before it departs. ** Those ** tanks would empty, and they would travel to Mars along with the Starship.
At Mars, they could be detached and saved for future use (at Phobos for example), while the fully fueled Starship is able to use fuel to dock with Phobos, or to achieve orbit around Mars, without having to risk flight through the atmosphere.
(th)
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I found this today. History of BFR/Starship, and some intersting information.
https://www.nasaspaceflight.com/2020/10 … on-rocket/
-There is indeed plans for Starships that function as in space Depots.
-In the article it is suggested that the Propellant Starship will have some lifting air body functions, and pehaps some small fins for guidance. I am pussled how they pressurize this one though. I do recall that they don't need as big a safety margin for uncrewed ships as per pressure.
-Also there seems to be an indication that the propellant starship will have ~40% less dry mass, then normal Starships. Don't hold me to that. I believe I read it in the article last night in passing. I am guessing that the Depots might have less dry mass as well.
Done.
Any starship of Falcon modified second stage would need a separate propellant tank to hold the fuels for payload delivery to the awaiting starship. It will need some sort of pump to move the fuel as well into the starship and a connecting hose or automated boom as we would not want any space walks to be required to refuel the starship with.
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]]>As a "So far" tollerated member here, I hesitate to enter into deep waters. Still, from the shallow end of the pool, I observe some things, while not in denial of what is presented as real by the better capable members.
At the start, I observe that SN8 is a prototype, and although SpaceX has come a long way, their efforts at this time must be "To do it at all". So, they probabbly allow a bit of overkill per dry mass and also have not perfected the "Art", to understand where they can reduce the overkill.
SN8 also being a prototype is also rather generic. It would not be sensible to push propellants to orbit with the machine.
I read that Elon Musk said that the propellant ships will look strange. If you make a propellant variant, it will not have the dry mass for lifting cargo or to have cabin space. This should be able to reduce dry mass on the way up. Also, on the way down, it will be basically a hollow shell, except for the header tanks.
I read that Elon Musk said that the propellant ships may not even need skydiving fins. However, that is "May Not". But I am guessing that if it has them, they will be less massive, and so will present less dry mass to lift, and less air drag on the way up.
So, you then have a mostly hollow shell comming down, it may be that the heat shield may be a bit less heavy.
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Someone here mentioned the notion that SpaceX may also have a type of Depot ship. I cannot see a reason why such would not be given enough solar assets to do active cooling.
If I were to speculate on the design of such a ship, I would hope, and I do say hope, to have it be a hollow shell on Orbit, and to have hybrid engines, that although not efficient for either sea level or vaccum preformance, might do. After all, all you would want to do is get it to LEO. Perhaps you might land it on rare occasions, but mostly it would be in space, not firing it's raptors.
Now with extreme speculation, I propose that you might make a variation of that, that you mated with a solar pannel/air braking system, which would never come down. Such a variant, might move a full load up to higher orbits using ion propulsion for efficiency, to fuel missions. To come back home, (LEO), after refueling a starship then ion drive to get to the fringes of atmosphere, and then aerobraking with the fortified solar pannel assembly, to achieve LEO again. For that maneuver, firing chemical engines might be part of the method.
So, I do think you have to make account of the possibility of perfection of art over time, and the use of specialized variants, to achieve what could be possible.
The situation should not be considered as without hope.
Done.
The surface/LEO two stage trip, and the exploration of possible tankers, is in the 25 May 2020 article titled "2020 Reverse-Engineering Estimates for Starship/Superheavy".
The revised Mars trip estimates are in the 21 June article titled "2020 Starship/Superheavy Estimates for Mars". This included looking at stopping in low Mars orbit.
I looked at the moon mission unrefueled, with the 120 ton inerts, in the 5 July 2020 article titled "2020 Estimates for Spacex’s “Starship” to the Moon". Unlike the 2019 numbers, this didn't look feasible anymore at the higher inert.
So, I looked at launching the Starship that lands along with uncrewed tankers, doing refueling in the vicinity of the moon. That was more feasible, although the number of tankers to LEO is very large. This was the 13 July 2020 article titled "Non-Direct to the Moon with 2020 Starship".
The heavier inerts make a huge difference in the performance levels you can get out of the "Starship" and "Starship/Superheavy" configurations. There is no way around that. But if they get the inert weight down nearer Musk's goal of 100 tons, the performance lies between what I calculated in 2019, and what I calculated this year.
GW
]]>First up is boiloff lose rate of which we are capable it seems of using a cryogen cooler to achieve near zero lose rates and hoping that that is part of the Starships design....
NASA cryocooler technology developments and goals to achieve zero boil-off and to liquefy cryogenic propellants for space exploration
https://www.esa.int/Enabling_Support/Sp … onstration
Agreed that engine out needs to be considered early until we have more engine flight data or more testing to prove out the engines capability after being in orbit for so long while refueling and then drifting to mars to be used for the landing phase. Of course the first refueling and landings of the cargo ships will give a good chunk of data for the engines use for mars long before we start out.
These landings and relaunch of used ships will also give the cycle times for reuse and give a good look at the heatshields resistance to failure for mars as well.
]]>I also looked at using Starship as a surface to orbit-and-back ferry vehicle based (and refueled) on Mars. That's the 16 September 2019 article titled "Spacex "Starship" as a Ferry for Colonization Ships", which might be of interest to RobertDyck and Tahanson43206. Not directly for the giant colony ship they are looking at, but as the transfer vehicle from it to the surface.
For anyone wanting to know what the Raptor engines can do when operated at full design chamber pressure, I have all those ballistics worked out in the 26 September 2019 article titled "Reverse-Engineered “Raptor” Engine Performance". The scope there covers both the sea level 40:1 bell and the vacuum 200:1 bell. Both use the same powerhead. I've got plots of performance vs altitude for both versions.
GW
]]>Thank you for the discussion you are having!
Please evaluate a Fourth Option .... Refuel the Starship as now planned, but instead of using ** that ** fuel (and oxidizer) to boost to Mars, use an orbital tug to provide the Earth Departure boost. ** That ** vehicle would be comparable to the heavy booster that is going to put Starship in orbit, but ** much ** smaller. It would remain in orbit to perform this simple duty over and over.
The number of tanker loads would increase. The number of tanker loads might even double. But ** that ** expenditure is only for expendable chemicals.
The result would be a fully fueled Starship arriving at Mars with plenty of fuel for maneuvers and even for landing if that is desired.
(th)
]]>Your third option makes a lot of sense. But it cannot be executed using Musk's Starship. The delta-vee capability is missing from that vehicle to stop in Mars orbit.
I looked at Starship to perform the same surface to low orbit ferry function on Mars that it plus Superheavy will do Earth. It can do that. But it cannot fly from LEO to LMO. Not even at zero cargo load.
Sorry. Your option will require a different vehicle or transportation system.
GW
]]>There's a third option. You implement some version of Lockheed-Martin's Mars Base Camp so you can remain in orbit to tele-robotically scour the surface, looking for shallow ice deposits to mine, to include a propellant tank to determine the feasibility of water extraction and transfer, a sort of mobile drill rig. Then and only then do you bother landing the propellant plant. After that you land the propellant plant on that block of ice, you begin industrial scale water extraction for transfer to the propellant plant Starship. After you have sufficient purified liquid H2O and purified liquid CO2, then you need to tele-operate the propellant plant to produce propellant in batches. Once you have sufficient propellant to transfer a load into an empty crewed Starship, then you can make the assumption that this process will continue to work successfully and land the crewed vehicle. I still think it would be best to only use Starship as a crew and cargo transfer vehicle on both ends, leaving Starships on Mars and Starships on Earth. The moon is so close that immediate return is possible, but even there if the plan is to operate a permanently occupied base, then they need to operate as transfer vehicles. We need tanker trucks to make runs between the propellant plant and a crewed Starship a few kilometers away. You don't want the base, the propellant plant, and the landing area for the crewed Starships to be co-located. You do want reliable heavy duty vehicles that can make regular milk runs between the three, carrying water, propellants, replacement parts, repair or monitoring crews, etc. The cryo-plant won't be permanently occupied, though. It'll have to be something you visit after each batch of propellant has been completed to inspect seals, pumps, etc.
]]>Why that much for the landing? My bet is they will find they have to light earlier (to aid the pull-up maneuver) and burn more, in order to reliably land in that thin atmosphere. Their own simulations show end of hypersonics in the 5 km altitude range, just about like I thought. You are seconds from supersonic impact unless you can bend the trajectory upward. I think the air is too thin to do that with only lift forces, even on lowland plains.
Much of the oxygen has to come from electrolyzed Martian ice. There is no other practical source. The hydrogen from that goes to the Sabatier reactor to make methane, using the carbon from atmospheric CO2. Which is why they need to mine subsurface ice in massive deposits, rather than process tons of slightly-damp regolith to make ounces of water. NOT practical!
Sending hydrogen to Mars to make methane from a Sabatier reactor is what you can do unmanned. Mining ice is going to take men. PERIOD! Unfortunately, until you have men there to mine ice, your propellant production rate will be slower, and you won't ever have enough oxygen. I have seen no proposals for robot devices that would get around this problem.
It's chicken-and-egg, which is what no one, not even Musk, will face up to. You need to be able to make the return propellant robotically, before you send the men. But you have to have the men there to mine the ice, or you will never make enough return propellant.
I'd like to see them succeed, and the sooner the better. But I am skeptical of the propellant-making capabilities that are required for this transportation system not to be a one-way suicide trip.
GW
]]>Rich is typical so let it be 4 x 240,000 = 960,000 of oxygen
960,000 + 240,000 = 1,200,000 kg of which originally that number was 100,000 kg to low to land with and most likely its even more if the tanks are not keeping boiloff low enough for the duration of the trip. I would hate to not have enough landing fuel for mars once we get to orbit after slowing down for mars entry....
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