Hannu2

I counted cancelled or failed space missions due to bad weather delays. Travelers have commonly very limited periods they must fly for various reasons but space projects can adapt to delays for many reasons. Launch windows are usually weeks long and very many Mars projects have succeeded in spite of delay of 26 months to next window.

Unability to fly in bad weather is not a bad problem in current of foreseeable applications of space flight. Payloads which need to be launched at exact time are very exceptional. Most projects take years or even decades and delays of months or years are tolerable (and actually very common). That point to point passenger flight is such application but it does not seem to be very realistic idea at all. At least in next couple of decades. There is not only technical problems but legal and bureaucratic issues too which may be much more worse, if international aviation regulations must be changed.

I understood. But my English skills (which may be bad, I am not native) say that paper rocket is not suitable word for that phase. Paper rocket is rocket under planning. And if you think for example other companies and operators, rocket under flight test program (Starship) or under finalizing for first flight to orbit (SLS) are much more potential than rockets in early planning phase (for example manned Mars crafts or proposed nuclear stages). Probably every company and space organization take Starship into account and estimate benefits, risks and schedules when they plan their own projects in paper stage, even they would eventually decide that it is better to take one of current production models. But no one even think about possible nuclear rockets of far future. Of course Starship or SLS are not in operational work yet (i.e. "ready") and it is not guaranteed that they will ever be. And Proton clearly is because it has very long history and you can routinely buy a standard launch. But it is not definition of "paper rocket", at least in my opinion. It may be that someone uses that word differently. But in any case it causes confusion to call project in test and finishing phase as paper project. SpaceX's phenomenal pace of development is easy to forget because Musk gives always those "aspirationally" unrealistic schedules which slip years. But if you look history there are no many examples of such rapid development even in superpower's almost infinitely funded projects. But I am sure that NASA is not serious with that manned Moon landing in 2024. It is clearly impossible if they do not accept very high risk level and increase funding immediately by an order of magnitude.

What is the point of all this complaining? We know that you do not like SpaceX and do not believe they could achieve success. But they will absolutely surely not cancel their projects if someone in Internet do not like or believe them. Let them try whatever they want. I would mention also lion's share of global satellite markets and real attitude to try some real development instead of empty talks like national space organizations (except Chinese who also attempt to develop their space operations). I would not give applauds for Nasa, Esa or Roscosmos (or governments funding them) for activities in last 2 decades. Drag can also be controlled by orientation of craft. There is no need for large corrections in pinpoint landing. Controlled drag is needed for last minute change of landing area which is not needed in civilian space applications. Even spacecraft could do it and there would be another landing rig nearby such a major change of flight profile would need bureaucratic paperwork of months in normal conditions and be practically illegal.

There is a clear difference between funded project which building work has began and "paper project" which has not made any expensive building work yet. Of course there are unclear occasions (of example in my country building work of building has juridically began if I throw one shovel concrete on ground and let it harden but if I dig a trench for basement it has not began). But both SLS and Starship has many essential and very expensive components, like engines, ready or under flight test phase. Billions of dollars have invested for both projects. They are currently work in progress and if they were cancelled before finish they will be failed projects but they have very clearly passed paper rocket phase several years and billions of dollars ago. I would say that Moon lander version of Starship (and other suggested landers) and all published manned mars-operations are currently in paper phase. They have no significant hardware yet and will need several orders of magnitude more funding than already used to be severe projects under construction.

Your source assumes coplanar circular orbits. Under those assumptions ejection inclination is always zero. You should calculate more accurate trajectories and maneuvers by using all orbital elements. It is much more laborious (for both, computer and programmer) but not mathematically very difficult. You find formulas and algorithms with quite clear explanations from the link below. You can calculate inclination and LAN for parking orbit from ejection velocity vector and parameters of departing body. Improper gravity model of KSP may also cause errors, which can be (very) significant if you plan Moho transfers or transfers between Jool's moons. http://www.braeunig.us/space/index.htm

That may be true from some very abstract philosophical point of view. Like wars could be ended if no-one would kill or poverty could be ended if wealthy people would always help poor. But practically that is very false. If you are worker you use units your boss order to use. If you are boss or company owner you use units customers want to. If you are politician you know that any law can not overcome conservative attitude and traditions. Eventually you can not find an individual in real world who can avoid imperial and other strange units without significant trade offs in practical life. Situation is not perfect in countries or scientific community which use SI-system. There are many historical special units in most areas which stay alive during decades. For example ångströms (1 Å =100 pm) and 1/cm as unit of energy in spectroscopy.

There is no way. Most of those people are generally against lifestyle and culture of western civilization. It is futile to tell that expansion to space is the only way to maintain development in long periods if someone wants to shut down industrial production and return couple of hundreds of years backwards (usually without understanding that they would not be counts or princes but practically serfs without human rights in extreme poverty if they survived through some miracle when food production drop 90 % without modern machinery, chemicals and highly productive plant varieties). Religious people who think that their god want humans to stay on Earth are probably even harder to convince benefits of space technology. Third group are just nitwits who can not understand complex processes and long timescales. Pretty hopeless too.

Carbon fiber is not established in large rocket booster tanks. It is very special thing which needs special properties. If there are high pressure carbon fiber gas cylinders they are not straightly usable in rockets. That SpaceX's "trade" means failure. Their composite tanks were not good enough to heavy booster and they did not see way to achieve objectives in predictable time and costs. There are also no other companies who use such tanks in their large rockets. SpaceX use steel and Li-Al and others Li-Al. That 304L is not "ultra strong space steel with 10 % unobtainium and cost of million per kg" but very basic stainless steel used in very many industrial applications. Especially in food industry because it is very safe. Also usual kitchen stuff, like forks, spoons and pots, are made from such steel. They said their will develop material later phases and I do not know are new SNs still made from commercial 304L steel.

Current rockets use very optimal tanks and engines. Every company develops their products continuously. If you take some values from another products, test articles or even theoretical values, they are scifi speculation and not facts. If someone knew how to use such materials and components in orbital boosters they certainly would use them (in two stage rockets to maximize payload per cost). Comparing existing real tech to some speculative values is very useless fact even it is formally true statement.

It is insane compared to current tech level and commercial or space program's needs. But long term trend for all transport devices is increasing size of units during development. Large size gives generally more advantages than costs. Maybe 18 m superrocket will be feasible when Starship has been in use for a decade.

It depends on what you do. If you use units occasionally and crude accuracy is enough it should not be hard, but if you are for example a machinist I can imagine it is easy to make mistakes with unfamiliar units when you are tired and boss nags about increased production demands. For me units are not difficult, it is just a factor. Easy to estimate crudely in head or calculate with calculator if an accurate value is needed. Strange habit to split inches in two's powers instead of usual decade system is the annoying thing. Especially larger divisions, like 7/64 inch.

I fear that authorities of local primate civilization may have problems with moar boosters to superheavy. Solid boosters are obsolete but 7 superheavies with asparagus staging would be nice next step, before hexagon of 19 stages. But I think that correct answer is "you began on too large planet with a species interested in too mundane things".

That is highly speculative option. SpaceX tried to make fuel tanks from composites and failed. It is clearly very non trivial task. No on knows how much development takes money or time and what results eventually are. Just take strenght of lightest composite and calculate some values is not very credible. But why we would not build two stage booster from those new advanced materials and get again benefits of multi stage rocket? There is already significant competition in small launches. There are small conventional rockets and rockets launched from plane. And there is also a threat that when huge starship begin to work as intended it takes markets because fully reusable huge craft may be cheaper than small expendable rocket. I am sure that those companies have investigates SSTO possibility but rejected it. It is like shuttle, many very advanced things are needed but no one knows how much it cost or take time to develop them. Governments may make overoptimistic decisions and keep programs running using loads of taxpayer's money even everything will not be realized as intended. But companies can not afford that.

The most realistic like options are probably boring for stories. But I think when (if) there are heavy battleships and warp missiles commonly used they have developed automated defenses against known weapons. Suitable defense weapon is always in readiness state and when missile is detected it is aimed and launched immediately. It is completely impossible to say. With you assumptions it is probably true but they seem to be very arbitrarily chosen combination of scifi and modern technology. If you use some other assumptions it may be very feasible to have battlecrafts with size of dwarf planet. Warp drives you described are so magic technology that we can not foresee what kind of detection, hiding, maneuvering or attack technology is available in that level. If spacetime can be manipulated maybe it is possible to form an event horizon around enemy ship and capture it. But maybe it is somehow possible defend by breaking that event horizon or even utilize it to harm attacker. Story can have whatever solution. All them may be criticized against reality but I think it is the whole idea of stories.

Also in Finland planks, nails and some other carpenter's materials are called by inch measurements. Everything is sold and official drawings is made in metric units according to European standards but inch is used in professional jargon and hobby carpenters too. Every store know to give you 98 x 48 mm plank if you ask "kakkosnelonen", which means 2 x 4 and packet of 75 mm nails if you ask 3".

Heading referenced to Earth surface is not defined. If you think in inertial coordinates heading is to east (I do not remember what definitions of zero and direction is used in this case). Orbit of standing object is very narrow ellipse and object is in apoapsis point. Inclination is equal to latitude and periapsis near the center of Earth. Or center of Earth if object sits on pole. Both coordinate systems are relevant in ascent. For example KSP changes from surface referenced frame to inertial frame during ascent (typically soon after 1000 m/s, I do not know if altitude or speed triggers the change). I did not check those values of Heading but they seem to be correct.

You can write some kind of administration over the whole operating area in your story. But even then there will be high risk operations. You may sell a cargo ship with monthly payment but probably want full prepayment for fighter ship if some pilot hero is going to conquer more solar systems from "bad aliens" to "our good civilization" or also for a research ship if some propellerhead claim that he has invented an ingenious new method to flee from behind an event horizon. Tracker and effective galactic police are pretty useless in such cases.

Answer is pretty obvious. SpaceX's bank account takes severe hit and metal workers get few months prolonged work contract. I think that only thing to do is to plan trajectory and building layout so that crashing rocket causes minimum damage to structures. It is impossible to save a rocket stage.

150 hours flight time is extremely overoptimistic. Electronic damage due to thermal cycling with low minimum, dust and wear in bearings or battery degradation is probable limits. Crashing due firmware error is also much more probable than motor damage (it was quite near already). Ingenuity's protection has not been done for months use. It will be good if it can do few scouting flights but I would not expect several months service life.

Of course barrier to activate massive destruction is high. But the larger number of people able to do so the higher probability is that worst happens. On Earth there are very few individuals who can begin massive nuclear attack from own initiative. Probably no one can, because all presidents have their inner circle who probably prevent such operation in case of psychosis. But if that artificial triggering of field collapse is possible, there will be more and more civilizations which can begin it. Every new increases probability and eventually, during billions of years, it happens. But it is very fictive speculation. I do not think it is ever possible if natural high energy phenomena, like black hole collisions or supernovae, have not enough bang for triggering.

If the universe is expanding as it seems to be, only finite part of it can interact due to finite light speed. Anything beyond observable universe can never affect to us. But even extremely small deviations (several orders on magnitude lower than observation limits) of known natural laws become very significant in such extreme extrapolations. Predictions to final fate of the universe are very speculative, even if they are based on best known science. Mass suicide works well as defensive weapon much like intercontinental nuclear missiles have worked decades on Earth. No one has realistic possibility to win in such situation. But if civilizations develop and many of them get ability to trigger collapse, risk that crazy dictator can launch it increases. It sounds that there will be work for action heroes in very far future.

I agree that honest competition is not very realistic option for states. But I hope that there is a little bit respect towards common effort to expand in space. Otherwise we get few military bases on Moon but no mining or significant science. I have heard those too. But I am quite sure that they are click bite topics and/or propaganda against those countries but government members do not really be stupid enough to believe that other superpowers disappear suddenly. There may be revolutions or other crisis in every country (also in western democracies) but usually they do not destroy states but just change leaders and redistribute property.

I think honest competition with respect to each other and rules (or good manners if there are not common rules, like in space investigation) is the best. If competitors feels each other enemies they use most resources to defenses and attacking instead of straightforward science and technology. For example nations use several orders of magnitude more money for their armies than for science. Military research produces sometimes usable things but most of the money goes to futile bureaucracy, practicing and display of power to enemies.

Higgs field have non-zero minimum energy. Some physicists have speculated that Higgs field may be in some kind on metastable state and it may be possible that it decays to lower energy state. I have understood that if such transition begins it expands at speed of light and nothing can stop it. It would change natural laws drastically and all current particles and their interactions would change. It would be impossible to know before it happens because there are not known ways to send information faster than light. Predicted probability of such event is be extremely low and it is not known is it really possible. Maybe you can write that some civilization (or cosmological level gangster boss) has a method to initiate such transition. I am surprised if no scifi author has already used it. https://en.wikipedia.org/wiki/False_vacuum_decay