I tend to look at the range of possible designs for reusable launchers going from variations of the Chrysler SERV to the SLS-as-what-the-shuttle-should-have-been. What I mean by that is the Shuttle would likely still be flying and continue to fly decades into the future (like the R-7/Soyuz) if a few critical details in the design had been different. But we went cheap and…there is no cheap.
The main feature of the Shuttle was the ET as the only expendable component and main structure for the rest of the stack to mount to. This was really the best idea in the Space Transportation System. Due to the rocket equation the expending of second stage hydrogen/oxygen tank structure while reusing as much else as possible works out well to maximize payload. Akin to fighter planes using a drop tank. The second excellent feature was the two boosters being ocean recovered. But that was pretty much where the good features ended and the bad features guaranteeing the Shuttle would fail began.
Liquid boosters instead of SRB’s would have been recovered and taken back to be inspected and readied for the next launch instead of broken down into segments, railed back to Utah, reloaded with propellent, railed back to site, and then reassembled. The limited diameter due to rail transport ended up limiting power and the payload of the STS- and all this was key to what guaranteed the Shuttle would fail.
The second worst feature of the Shuttle was mounting the SSME’s on the Orbiter. This necessitated the side-mounting and the Orbiter itself meant most of the payload of a Saturn V class launcher was wasted lifting a 737 size glider a couple hundred miles up so it could come right back down. And the heat tiles ended up being a tremendous eater of man-hours and expense. By having an engine module at the bottom of the ET that returned separately for reuse the STS could have placed the payload, any payload, on top of the stack. And this version of the Shuttle would have looked much like the SLS.
The Chrysler SERV (like the Kankoh Maru) was the other more radical concept and is very interesting. I think putting a 260 inch solid rocket booster in the center of it and dropping it out of the bottom after use, and a couple other features changed, would have resulted in a practical launch vehicle with nothing being expended. Which is of course what everyone seems to think is the main point. I am more about bowing to the reality of the rocket equation and expending that core/second stage tankage if that results in more lift. That large gain in payload by expending at least a fuel tank is what I think John Shannon was expressing when he said “reusability is a myth.” This is actually an improvement on the benchmark Falcon which not only expends the tankage but also the engine. It was a sad day when they killed Sidemount…we might be back on the Moon by now.
https://www.nbcnews.com/id/…
I believe future iterations of the SLS can be that best-possible-shuttle and are the best way to go.
———————————————————————————————————————————-
Climate Change is the single most critical issue facing civilization and the only way to provide the energy for a western standard of living to everyone on Earth is Space Solar Power. The Moon is the carbon-free factory to build the Space Solar Power Satellites and the only solution to Climate Change. Entrepreneurs are not going to make it happen- only a state sponsored program, a Green New Space Deal is going to succeed.
Bob Mahoney· Your first sentence is perhaps the most unscientific statement made in these pages in a long time. Its decided absolutism (across four lobes of inquiry, even!) rivals (if not exceeds) quite a bit of badly considered religious dogma. Your second and third sentences aren’t much better in this regard.
Wow. It is breathtaking (in a tragic way) to witness such confidence in conclusive prognostication. The advice parents are wont to offer their teenage children when the kids offer up similarly toned absolute declarations comes to mind: “You should move out now while you know everything.”
Richard Seaton· It is the single most critical issue. A western standard of living requires a great deal of energy and for 8.5 billion by 2030, 9.7 billion in 2050 and 11.2 billion in 2100 there really is only one way to do it. Really. Entrepreneurs are not going to spend trillions on a half century long project to essentially give free electricity to most of the world’s poor. So…your denial of reality is breathtaking.
Bob Mahoney· 1st post:
Single most […] issue facing [implied: all] civilization.
Only way.
for a [implied: required] western standard of living to everyone on Earth.
only solution.
only a state-sponsored Green New Space Deal is going to succeed.
2nd post/reply:
is the single most.
[implied: required] western standard of living
Only one way.
I’ll concede that you are consistent. But you seemingly missed my single most critical only point.
Richard Seaton· I explained it and you are obviously not going to acknowledge that building powerplants, factories to build wind turbines, solar cells, all of that infrastructure on Earth, cannot keep pace with the demand for a western standard of living without producing more carbon and greenhouse gases. Antennae fields, on the other hand, are not significant producers and factories on the Moon are not going to affect Earth. See how that works? It is the only way. You can mock and condescend but you cannot change the reality that is climate change.
Dick Eagleson· Well, at least you’re consistent. Your farcical prophecies about the size of the world’s population 80 years hence is as delusional as all the scaremongering about alleged rises in global average temperature and sea level made by your fellow Warm Doomists for the same interval.
Marcel· The Earth’s oceans contain about 4 billion tonnes of uranium, nearly a thousand times the amount of uranium in terrestrial reserves. Marine uranium resources are derived from the oceans interaction with 100 trillion tonnes of uranium within the Earth’s continental crust. So uranium is actually a renewable energy source since uranium can be perpetually mined from seawater– as long as the Earth’s oceans exist.
Plus spent fuel from uranium could be recycled to produce 30 to 60 times more carbon neutral electricity.
And I didn’t even mention the abundant terrestrial reserves of thorium that are more than three times as abundant as terrestrial uranium reserves.
So there is no shortage of carbon neutral energy resources– on Earth. Marcel
Richard Seaton· Chernobyl and Fukushima plus the vast processing and reactor construction infrastructure on Earth you are proposing is a non-starter.
Marcel Williams· Chernobyl, of course, was a facility with no containment structure which is something that Russia and the Ukraine don’t do anymore. All US commercial nuclear reactors have containment structures.
At Fukushima, only one person died of radiation poisoning; I believe the individual actually fell into the reactor.
Unfortunately, the earthquake and tsunami killed about 16,000 people. A dam ruptured in the area, wiping away five homes, killing 8 people.
Nuclear reactors actually require much less material per kilowatt produced than renewable energy and substantially less land area. Nuclear also produces at least 300 times less toxic waste than solar panels per kilowatt produced. But if spent fuel is recycled then they’d produce about 9000 to 18,000 times less toxic waste than solar panels per kilowatt produced. Marcel
Richard Seaton· Unfortunately, your promotion of “safe” nuclear reactors in every country on Earth might be something the nuclear industry wants to see but it is not the solution to climate change. Again, to provide the vast amount of electricity necessary for 11 billion people to enjoy a western standard of living would require tens of thousands of nuclear power plants. From a Smithsonian article: “All told, the nuclear reactors in the U.S. produce more than 2,000 metric tons of radioactive waste a year, according to the DoE—and most of it ends up sitting on-site because there is nowhere else to put it.” Transuranic waste lasts for a thousand years. There are plenty of factoids inferring nuclear waste is not that bad, that it is just a minor problem that quickly diminishes. It is not a minor problem. It is not a safe source of energy and Space Solar Power is the far better option. What people are doing that promote nuclear is distract the public from the correct path identified by Gerard K. O’Neill in the 1970s.
Dick Eagleson· As Marcel correctly notes, recycling of nuclear fuel reduces the mass of so-called “nuclear waste” to trivial levels. The “problem” of “nuclear waste” disposal is entirely one created by the crackbrained U.S. prohibition on recycling such “waste.” That prohibition is a product of the politics of ignorance and fear of which you, and the rest of the American Left, are very much an exponent.
Richard Seaton· Trivializing Chernobyl and Fukushima and calling statistics from The United Nations projecting populations “farcical” is typical of the recent war on the truth. It is all fake news if you don’t like it. The American Left brought an impoverished people out of the great depression with The New Deal, defeated Nazism, and put Americans on the Moon. The recent radical right populism, which your climate denial would indicate you are an exponent of, has caused the needless deaths of at least a hundred thousand.
A Green New Space Deal is the hope of the future and the correct path. Those that scream bloody murder at anything not involving billionaires and their bought dog politicians lowering taxes to nothing and ending all social programs are the great danger.
oldengg· Space solar power is fine for use on satellites and on the Moon. But to transform energetic solar photons to electrons (solar cell) then transform those electrons into less energetic microwave photons (gyrotrons) and then beam those microwave photons down to an antenna farm (that is at least as big in area as the equivalent solar energy farm) and finally transform those microwave photons back into electrons that are fed into the grid only pencils out if there are no competing terrestrial-based electric power suppliers.
Unfortunately for space solar power there are such suppliers (direct solar, wind, nuclear). So O’Neill’s idea amounts to generating electrical power in space where it’s extremely expensive to produce and then trying to sell it at a profit on Earth where electrical power is much less costly to produce.
Richard Seaton· “-if there are no competing terrestrial-based electric power suppliers.”
I will just keep explaining this over and over: Climate change means nothing terrestrial can “compete” with space solar power electric suppliers in terms of carbon and greenhouse gas emissions. And that is the critical issue for civilization.
——————————————————————————————————————————–
The defense industry is where 1.2 trillion dollars (it will likely be a trillion and a half) are now being sunk into new ICBMs, stealth bombers, and missile submarines, continuing over the next 30 years. The total lifecycle cost of just the new submarine fleet of 12 boats is estimated at $347 billion. And then there is the Panama Canal, the Hoover Dam, and also the cost of construction of the Interstate Highway System was approximately $114 billion (equivalent to $530 billion in 2019). Just as the interstate is a defense industry adjutant so is energy and of course Climate Change is a huge DOD issue.
No “commercial” entities are going to colonize space anymore than they are going to turn Antarctica into another Eastern Seaboard. The long list of fanboys on this forum are living in an alternate universe only a couple notches down from Trumpworld. Most agree on the main points of NewSpace dogma and in my view it is the worst thing that has ever happened to space exploration. It is a dead end and has set any progress in space back a decade and the damage is accumulating.
Rescuing civilization from the catastrophe that is climate change is eerily like the virus saga we have watched play out these many months. Just as one man is largely responsible for at least a hundred thousand needless deaths it was one man, Charles Koch, who paid for climate change denial and unless that damage is undone it will be several orders of magnitude more than a quarter million who will die.
And there you have it; it was Gerard K. O’Neill that wrote the correct plan to power civilization carbon free and expand humankind into space- not the John Galt/Howard Roark/Tony Stark entrepreneur. He and the rest of the Neoliberals are the problem. They only care about one thing- money. Human life is secondary when it should be first and dictate our actions. Bezos makes alot of noise about following O’Neill but he is, so far, just promising to drain the swamp like someone else did.
I wish Bridenstine was staying on for two reasons- his advocacy of exploiting lunar resources and because he recanted his climate change denial.
The big opportunity now is making Space Solar Power as big a part of The Green New Deal as possible.
———————————————————————————————————————————-
And there is the dead giveaway that nobody is ever going to live on Mars. Due to no air and hard radiation it would be an underground existence. Due to not enough solar energy to power closed loop life support systems these tunnel communities would depend on nuclear power plants. What products will they “sell” to pay for their necessities? It is a joke. Not to mention that Martians would likely never be able to return to Earth after a certain number of years- or if they were born on Mars.
Space colonies, on the other hand, would have 1 gravity and travel to other artificial moons and nearby Earth would be commonplace, eventually with hundreds or thousands or tens of thousands of city sized habitats. The economic engine to start space colonization was envisioned by Gerard K. O’Neill: Space Solar Power. Which also happens to be the only solution to providing the energy for a western standard of living to the population of Earth carbon-free and thus solving climate change.
A Space Solar Power cislunar infrastructure would eventually enable beam-propelled single stage to orbit space-liners to begin decreasing Earth’s population as more and more miles-in-diameter habitats are mass-produced. Until in a few centuries Earth is a sparsely populated pristine “adventure” destination and tens of billions live in space.
——————————————————————————————————————————–
Life would be quite different in a 1 G Sphere compared to Mars. Anybody living on Mars would dream of one thing- living on Earth. Anybody living in a Bernal Sphere would not have to dream, they would be able to visit Earth or any other Sphere easily enough and not travel months- and they would have low or zero gravity immediately available as well as normal gravity. A miles-in-diameter Sphere is an immense volume with a vista that will not induce claustrophobia. Mars would not be that way. Mars also has a deep gravity well; too much gravity to make landing or escaping easy and not enough to keep humans healthy. Why go? The resources can be had from the Moon or transited from icy bodies. Granted those icy bodies are farther out than Mars but lifting volatiles out of the Martian gravity well is a spectacular expense in comparison.
This was all researched in-depth in the 70’s by O’Neill and his students. I profoundly disagree with the NewSpace dogma that Mars is the second home of humankind. While I am criticized for maintaining this strong stance…it is a matter of wasting time and resources on what I believe is the wrong path. When I am told to not be so hardline I have to ask them the same thing.
Ice on the Moon 