Exoscientist

A great influence in developing funding and support for space among the public is psychological: Scenario 1.): Public: When can we have continually inhabited stations on the Moon? Answer: maybe we can send the first landing mission in 2029. But it’ll cost perhaps $8 billion per mission amortized over total program cost like Apollo did, in current dollars, and wind up being cancelled like Apollo was. Public: When can we send manned missions to Mars? Answer: maybe by the 2030’s. Scenario 2.): Public: When can we have a continually inhabited stations on the Moon? Answer: we can launch a manned mission tomorrow. They’ll cost in the range of $100 million per flight, comparable to flights to the ISS. So we can have continually inhabited stations on the Moon tomorrow. Public: When can we send manned missions to Mars? Answer: we can launch manned missions tomorrow. They’ll cost in the range of $100 million per flight, comparable to flights to the ISS. So we can launch them, in fact several of them, every two year launch window. Robert Clark

AUGUST 26, 2024 China proposes magnetic launch system for sending resources back to Earth by Matt Williams, Universe Today https://phys.org/news/2024-08-china-magnetic-resources-earth.html The problem is even if publicly it is described as merely a transport method from the Moon to the Earth, any other country has to regard it as potentially an indefensible weapon because due to the long distance from the Moon to the Earth even a deviation in pointing of a fraction of a degree could result in its landing point instead of being over the ocean winds up being over a city. By the way, I like the mention in this article of the Robert Heinlein novel, The Moon Is A Harsh Mistress, which first described the idea of projectiles being shot from the Moon to the Earth as a weapon. Bob Clark

Is China planning to weaponize the Moon? https://youtu.be/eElDqTNe4oE?si=hv8Y3tgo9gBDfbF_ China wants to build a 1 megawatt nuclear reactor on the Moon, 10 times the size the U.S. is planning on. Why? Evidence suggests it’s for their electromagnetic launcher they want to use for sending resources from the Moon to Earth. This is analogous to the SpinLaunch™ being constructed on Earth for reducing the cost to LEO. But on the Moon with no atmosphere and much reduced gravity it can send the payload all the way to lunar orbit and even all the way to Earth. Being just electrically powered the launches will be at just the cost of generating the electricity. But it needs to be kept in mind it could send anything, anywhere on the surface of Earth. When you realize the Chinese space program is just an off-shoot of their military the possibility arises it could be used as a weapon. “Mr. President, we must not ALLOW a spin launch gap!” (With apologies to “Dr. Strangelove”.) Bob Clark

The capabilities of the expendable Superheavy/Starship are spectacular, 200 to 250 tons to LEO now. What’s even more astonishing is the cost is only in the $100 million range. This means we can send a manned-capable Mars mission not in the 2030’s but literally in just a few days with the IFT-5 stripped of its reusability systems to get that max payload with an F9 upper stage strapped atop it, and for costs for what we spend to send astronauts just to the ISS. The dream of manned flights to Mars is already here. All that is required is to recognize it. Bob Clark

Robert Zubrin has noted that the SuperHeavy/Starship can do Moon and Mars missions with no refueling flights nor SLS required if given a smaller 3rd stage that would actually serve as the lander, a mini-Starship if you will: Dr. Robert Zubrin - Mars Direct 2.0 - ISDC 2019. https://youtu.be/9xN1rqhRSTE?si=8unKEkYOxl4gQT0i Then it is important to keep in mind SpaceX has an existing stage that can serve for the purpose in the fully man-rated Falcon 9 upper stage. But you need the higher payload capacity of the expendable SH/SS at ca. 200 to 250 tons to be able to do it in a single launch. This is quite remarkable when you consider Elon has said the launch of the SH/SS only costs ca. $100 million. Then the implication is if the upcoming IFT-5 in a few more days were stripped of reusability systems so that it’s payload capacity was 200 to 250 tons, then that launch itself with a Falcon 9 upper stage as a Earth departure stage/lander could do a demonstration mission for single launch missions to the Moon or to Mars. We could have Moon or Mars flights now at costs we are spending for flights to the ISS. Robert Clark

Ok I’ll take all look at the original reporting. Bob Clark

Actually, they can’t know that because the astronauts are not actually in the capsule. They are on the ISS hearing the sounds through speakers on the capsule. Then the speakers can be picking up sounds actually in the capsule. Bob Clark

Not likely. Probably the same as what happened on the first Chinese manned spaceflight in 2003: Who or What Is Knocking On His Spacecraft? | NASA’s Unexplained Files. https://youtu.be/ioJsRQ53IEM?si=xc4Arfx6ZadjG7lg It’s believed to be differential expansion due to thermal differences. Bob Clark

The sh*t just got real: according to OIG, Artemis IV, the first landing mission, can’t happen until 2029 because that’s how long it’ll take to get the needed ML-2 ready: https://youtu.be/-i0EH1ibCVg?si=NllGFepDET88aIBv But China plans to land men on the Moon BEFORE 2030: China plans to put astronauts on the moon before 2030 News By Sharmila Kuthunur published May 31, 2023 https://www.space.com/china-moon-landing-before-2030 Then China beating us back to the Moon is not just a theoretical possibility. It is now a REAL possibility. Bob Clark

I found out that the $68 million price for 45 tons is for the partially reused New Glenn where the booster is landed downrange. So the comparison actually should be made to the price per kilo of the partially reusable F9 when it lands the booster downrange. So at $40 million for 17 tons payload for partially reusable F9 that’s $2,350 per kilo. And at $68 million, if true, for 45 tons for New Glenn, that’s $1,500 per kilo. So if SpaceX did want to reduce the price to match New Glenn reused price per kilo, it would reduce the reused F9 from $40 million to $25 million, still a significant reduction. Robert Clark

Blue Origin is finally planning to make a launch of New Glenn later this year. Blue Origin has not revealed the price for the New Glenn. The only estimate price I’ve seen is an estimate by ArianeSpace as a point of comparison to the Ariane 6: SPACE Amazon signs massive rocket deal with 3 firms, including Bezos' Blue Origin, to launch internet satellites. PUBLISHED TUE, APR 5 2022 7:00 AM EDTUPDATED TUE, APR 5 2022 12:17 PM EDT Blue Origin will use its New Glenn rockets to fly the 12 Kuiper missions it will host. Per CEO Bob Smith, New Glenn is going to deliver 61 Kuiper satellites per mission. While Blue Origin does not currently have an official target date for New Glenn's first launch, CNBC has previously reported the rocket is expected to debut in 2024 or later. The company has not publicly revealed a price for New Glenn launches, but an Arianespace estimate two years ago put the Blue Origin rocket at $68 million per launch. While both companies were founded by Bezos, Blue Origin is separate from Amazon. https://www.cnbc.com/amp/2022/04/05/amazon-signs-rocket-deal-with-blue-origin-arianespace-ula-for-project-kuiper-internet-satellites.html IF it really turns out to be that price, still a big IF, then it would be a better price than the Falcon 9 new of $67 million while being twice the payload of the F9 at 45 tons to LEO. I do think it is possible for a mid-size launcher to be comparable to the Falcon 9 in price following the commercial space approach of private financing. That would put the New Glenn though in the range of $120 million, having twice the payload capacity of the F9. IF it really does turn out to be ca. $68 million, then that would be a major development In having a rocket half the price per kilo than the Falcon 9. We’ll likely know for sure later this year when New Glenn makes its first launch. IF it does, then this might give price incentive for SpaceX to cut the price of the Falcon 9 in half. Note Elon once said the production cost to SpaceX of the Falcon 9 is only $15 million. So they could still make a profit though not as profitable as before. IF it does, then It might also give a price incentive for SpaceX to offer an expendable Superheavy/Starship. The cost of the SH/ST is ca. $100 million. At a payload for expendable of 200 to 250 tons, this would be a price per kilo less than the Falcon 9 even as reusable, and even less than the supposed price of a $68 million New Glenn at 45 ton payload capacity. As I have argued, offering an expendable SH/ST would be a transformative advance in spaceflight since it makes possible single launch missions both to the Moon and Mars at a price comparable just to the ISS that can be demo’ed literally by the next IFT-5 flight in a month by stripping off the reusability systems to get the high 200+ ton to LEO expendable payload. Bob Clark

Thanks. But I can’t tell what are the rocket components. Bob Clark

A exciting prospect is we already have the capability to do sustainable habitation for the Moon or Mars. For the manned Artemis missions, SLS and Orion cost $2 billion each per launch. SpaceX got a $4 billion contract for 2 Starship HLS’s, so $2 billion each. Boeing EUS, Advanced SRB’s, Gateway, at least total another billion and likely closer $2 billion. Then manned Artemis ~$8 billion per launch. This is clearly not a sustainable approach to lunar habitation. For the Apollo missions, I asked ChatGPT what were the per launch costs in current dollars. It’s response was: The Apollo program, which included a total of 17 missions (from Apollo 1 through Apollo 17), cost approximately $25.4 billion in 1973 dollars. To estimate the cost per flight in today’s dollars, we’ll follow these steps: 1. Adjust the total cost for inflation: • The cumulative inflation rate from 1973 to 2024 is approximately 5.8 times. This means that $1 in 1973 is worth about $5.80 in 2024 dollars. Total cost in 2024 dollars = $25.4 billion x 5.8 = $147.32 billion 2. Calculate the cost per flight: • There were 17 Apollo missions, including the uncrewed and crewed missions. Cost per flight = $147.32 billion/17 = $8.67 billion per flight Summary: The Apollo program cost approximately $147.32 billion in today’s dollars, which breaks down to about $8.67 billion per flight on average. And we already know Apollo was not sustainable. In contrast, ~$100 million for expendable SuperHeavy/Starship at 200+ ton capability gets single launch missions to the Moon at costs nearly two orders of magnitude cheaper than Apollo or Artemis. This is in the same range of what NASA spends for just flights to the ISS. For Mars, NASA once presented a plan to the George Bush, the senior, administration for a Mars program for a total cost of $500 billion. This was promptly rejected by the administration. These large cost estimates led Robert Zubrin to propose in the early 90’s his Mars Direct approach, where propellant for the return flight would be generated at Mars. This would require only 2 launches of Saturn V class launchers at 100+ ton capability. With the development of the Starship at 100+ ton ability reusable, Zubrin proposed using it in his Mars Direct 2.0 proposal. He contrasted this from the SpaceX approach of using multiple refuelings here: Mars Direct 2.0 - Dr. Robert Zubrin - IAC 2019. https://www.youtube.com/watch?v=z5k7-Y4nZlQ Zubrin notes by just using a small 3rd stage/lander you would need no refueling flights. But you have to wait until the time the Starship becomes reliable for reusable manned flights. In contrast the expendable version with its higher payable capability can launch now and needs only a single launch, not two. Demo flights to either the Moon or Mars can literally launch within a month on IFT-5 if stripped of its reusability systems to get the 200+ ton payload capability. Bob Clark

Thanks for that kidney stone example. 99.9% of the time choosing the opinion of someone who has expert knowledge on a topic will give the better choice over someone who has meager knowledge on the topic. For instance, the auto repair shop open for decades to fix your transmission over the guy who says he once watched his grand pop do it when he was a kid. But that 0.1% where it gives the wrong choice are so important that it needs to be kept in mind. For instance, the almost all physicists in the early part of the 20th century who depended on an “aether” to explain electromagnetism versus Einstein not yet granted a ph.d. who proposed variable space and time. In your kidney stone example it is an unfortunate fact that nowadays the medical “authorities” would recommend expensive, and profitable to the drug makers, prescription medications for treatment over treatments that would work better that cost virtually nothing. Bob Clark

EVERYONE uses appeal to authority but it should be recognized that is no guarantee of the validity of one side of an argument. For instance, a team of cardiologists with decades of experience recommends someone should get open heart surgery versus some guy who just read on the internet you can cure heart disease by drinking lemon juice. I’m suspicious that this guy who posted this comment posted anonymously from a social media account. Nature is the most prestigious science journal in the world. Most people would proudly give their real name and industry or university affiliation when making a contribution to that journal even if only for a comment on a published research paper. I suspect if he gave his real name and affiliation it would be revealed he was connected to SpaceX, or his knowledge is in fact in an unrelated field. About the relatively small difference in delta-v noted by that commenter, it should be kept in mind the authors of the paper argue the specifications SpaceX has provided make it infeasible it could accomplish a round trip for even 12 crew members let alone something of the nature of a passenger ship to carry 100 passengers: Conclusion This paper has compiled a feasibility analysis for Starship based on a published mission scenario and extrapolation of existing systems, where information about Starship had gaps. Using typical analysis methods, a mass budget for the system and subsystems was established. A Lambert solver was applied to identify the minimum ToF and Δv. It has been shown that there are currently several gaps in the available technology to conduct a Mars mission as sketched by SpaceX, e.g. concerning ISRU capability, power supply and the performance of Starship itself, which based on the mass estimate presented here, is incapable to conduct the mission as proposed by SpaceX. Especially, the ToF limits published by SpaceX are found to be unrealistic and cannot be held with the current design, requiring at least further improvement of the performance, some are outright physically impossible (i.e. Mars cannot be reached within 30 days with such a transfer vehicle). The current estimate does also not allow the return flight of Starship. Even with an unrealistic 100% recovery rate of consumables, the mission was not feasible for a 12 person crew per Starship, let alone for the SpaceX published 100 person crew. Further technology development is required, to supplement this launch and transfer vehicle and enable Mars missions. This is affecting Starship itself, but also infrastructure elements needed for the SpaceX proposed mission, especially those required for ISRU-based production of propellant. With the information currently available a Mars mission with Starship is not feasible. A small difference in delta-v of about 100 m/s out of 3,400 m/s is not likely to be allow a vehicle that can’t reasonably manage a round trip for 12 to be able to do one for 100 people. Robert Clark

I didn't say he was wrong, only that we couldn't know if he was knowledgeable in the area. But we can see that he was being disingenuous in implying the difference was sizable. The difference is relatively small so the conclusions still hold. Bob Clark

However, the comment is from an anonymous user posting from a social media account. So we can’t know if the commenter has any knowledge in the field. Bob Clark

Article in Nature does not find Mars Starship missions feasible: About feasibility of SpaceX's human exploration Mars mission scenario with Starship. Scientific Reports volume 14, Article number: 11804 (2024) https://www.nature.com/articles/s41598-024-54012-0 Bob Clark

Thanks for that. I used to listen to those FISO presentations all the time. Sort of forgot about them. Looks like a good detailed presentation of their proposal. Holder is a former Air Force officer so makes sense he would be able to get the Air Force interested. Bob Clark

Could that for example take the specs for the Delta IV and Atlas V rockets and accurately output the payloads to LEO, GTO, etc.? The Silverbirdastronautix.com payload estimator can do that within about 10% accuracy I’ve found. But it does have wide cited error bars, i.e., you can only be sure of the answers within that rather large error range. Another thing I want to estimate is fast flights to the Moon or Mars. For instance Elon once said the expendable Starship might have a dry mass of only 40 tons. That combined with a 380s Isp would allow 1 month flights to Mars with just chemical propulsion: That is just an estimate though based on the idea the departure speed is so fast the trajectory would be almost straight-line. It would be nice to have an actual trajectory sim that would calculate this more definitively. With departure speeds that high it should mean near straight-line trajectories from LEO to the Moon also, with greatly reduced travel times. We might want this with commercial flights to the Moon by, for example, SpaceX coming into play in a near term time frame. With just a 3.1 km/s escape velocity, we can reach the Moon within 3 days. How fast from LEO to lunar orbit with, say, 12 km/s delta-v available, taking into account you also have to slow down? Could the travel time be reduced to hours? Bob Clark

I remember asking on this forum once why Kerbal used Kerbin and Mun, rather the real Earth and Moon and other real planets in the Solar System. I remember being not really being satisfied with the answer. I think with the interest in universities and schools worldwide in spaceflight, there would be a great deal of interest in having a program where they could design real rockets for making real missions anywhere in the Solar System. Bob Clark

This part must be what they were just “hoping” for. If true, it would mean a mass ratio of the rocket itself aside from the payload of 60 to 1. That’s not reasonable. There is also the fact the 20 kg tank plus 10 kg engine section would already be 30 kg with no mass left over for any other systems. Plus, running the numbers, with a dry mass that low, you would get payload to LEO in the range of 50 to 60 kg, not the ~10 kg they are claiming. The Mockingbird rocket had a more realistic 20 to 1 to mass ratio, with a 75 kg dry mass. Bob Clark

On their LinkedIn page, Sidereus said their engines are pump fed: https://www.linkedin.com/posts/luca-principi-2801981a9_cold-flow-tests-on-the-eos-mr-5-engine-activity-7214905823716646912-0eqv The company co-founder gave an interview on Next Big Future about their rocket: Bob Clark

Too bad KSP2 didn’t take off. Couldn’t more exposure and revenue be generated by marketing it as an actual commercial sim for spaceflight to orbit and interplanetary trajectories? There is nothing in the open market that does this now in an accurate way. I like using Silverbidrastronautics.com payload estimator but it’s at best only within 10% accurate and it also has wide potential error bars. It also has poor accuracy for large SRB’s like the space shuttle, SLS, Ariane 5/6. Governmental software like POST and OASIS are ITAR restricted and are highly non-user friendly. Believe me, I tried. KSP being European would not be subjected to ITAR. Bob Clark

But wasn’t that the case also with KSP1? Bob Clark