Nibb31

Did I say it was pointless? My point was that in 1000 years, people's mentalities and preoccupations will be totally unrecognizable to us. Humanity will have evolved into something completely different from anything we know. So yes, space travel might turn out to be irrelevant to them and a technological dead end. Why would my made-up predictions be any more unrealistic than somebody else's?

Not really. They might be for water or some sort of coolant loop... There doesn't seem to be any documentation on the Internet about the implementation details of the docking interface.

My prediction is that there will be no major change in space exploration infrastructure. The laws of physics will remain the same, interstellar travel will remain impractical, there will be no free lunch, and we'll eventually accept the fact that there is nothing out there for us. As a species, we might finally realize that the only hospitable place for us to live is here. There is no point in colonizing planets where we can't survive without a full EVA suit and constant supplies. Sending people into space will always costs huge amounts of energy for very little benefit. It will remain a niche activity, for research and the occasional rich person's joyride. As for the thrill of exploration, discovery, and adventure, we can have it by plugging a connector into our spinal cord. When the VR experience becomes indistinguishable from reality, we will no longer need to risk our lives or spend valuable resources travelling to the stars or anywhere else. Space travel, like any sort of travel, becomes useless to us. We free ourselves from the physical world, we transcend our physical bodies and become all-powerful. Instead of exploring the universe and hitting physical barriers, we get to the stage where we can create our own universe without barriers. And then somebody, somewhere in that virtual universe stumbles on this thread and has a good laugh at all the silly ideas about space infrastructure.

This is a picture of the Progress docking port. So if you are correct about Progress having fuel transfer capability and not Soyuz, then the difference between the two seems to be the two silver valves just above the two grey locating pins that are replaced by blanking plates on your Soyuz picture. The ATV also had fuel transfer capability, and it also had those valves, with red covers on this picture. So I guess those are what you're looking for.

Prospectives that are 1000 years in the future are meaningless. Humanity, culture, civilization, politics, technology, and moral values will be completely alien to us, just like the World of the 21st century would be be completely unrecognizable to someone from the 11th century. 50 years ago, nobody even imagined the Internet and cell phones. 100 years ago, nobody imagined nuclear submarines and supersonic airliners. 200 years ago, nobody could imagine cars or movies. Whatever the World becomes in just 100 years is simply unimaginable to us. Any predictions you might have in this thread will be as laughable in 100 years as the paintings of "the year 2000" from the the 19th Century. Let alone 1000 years ! For all we know, we might go extinct in 200 years, or we might regress into some dark ages, or we might be building colonies on Europa, or we might simply be turned into machine-fed larvae living in a matrix-like virtual reality with no need for space travel at all... My bet is on the latter.

ISPRs are standardized: https://en.wikipedia.org/wiki/International_Standard_Payload_Rack The ISS lab modules and are designed around the standard ISPR racks. The ISPR racks are designed to fit through CBM ports. Changing the ISPR standard would require refitting the USOS lab modules. The ISS is a complex machine. You can't change one system without affecting other parts of it. Because they serve different purposes. The CBMs are wide and designed to bear structural loads. They are the large "doors" you see on the inside of the ISS. Because they are large, they do not have any mechanism to mate when they are not perfectly aligned. Modules must be guided very precisely into position with an arm. CBM berthing requires an arm, which means that it was not possible before the Shuttle brought up the SSRMS. The Shuttle itself could only dock to the PMAs, but it carried cargo (ISPR racks) inside MPLM modules. They used the arm to remove the MPLMs from the Shuttle payload bay and to attach them to CBMs for cargo transfer. Docking ports are not designed to support as much load but they provide autonomous docking without assistance from the outside (which is a safety requirement). They are narrower and more complex. A docking port that provided as much clearance as a CBM, while providing some sort of retractable guiding mechanism would be heavier, larger, and more expensive than a CBM. So CBMs are a requirement for cargo vehicles, because of their clearance, and docking ports are a requirement for crew vehicles, because they allow emergency evacuation. Exactly. Docking ports are designed to tolerate some degree of axial misalignment. They have soft-dock and hard-dock mechanisms that retract to pull the two vehicles together. CBM ports require near-perfect manual alignment.

And how do you get that spacecraft onto the surface of the planet without deorbiting and landing it first?

Space probes already use aerobraking for orbital insertion. Magellan used it first at Venus in 1993 and pretty much every mission to Mars orbit has used it since MGS in 1997. There is no need for a heat shield as simply skimming the upper atmosphere with solar panels deployed causes enough drag to slow down the spacecraft without generating too much heat. It doesn't work like in KSP where the atmosphere has a hard limit. They usually do it over several weeks or months with many periapsis passes.

The power, data, and fluid transfer connectors are on the outer ring of the docking port.

Berthing is when the vehicle is captured by the arm and attached to a CBM port. CBM ports do not support docking. They were primarily designed for orbital assembly of the USOS modules with the robotic arm. Docking is when the vehicle actively docks with a docking port. The only ports that support docking are the Russian hybrid ports, the US APAS ports (which are unused and obsolete) and the future LIDS/NDS (which will be fitted to the APAS ports but are not available yet). Only the Russian hybrid ports support fuel transfer and are in a location suitable for reboosting the station. One of the requirements for cargo vehicles was to use the CBM ports, because these are the only ports large enough to transfer ISPR racks. You can't fit those interchangeable rack modules through any of the available docking ports. HTV, Dragon, and Cygnus don't dock. They berth to CBM ports, just like Dragon. ATV and Progress dock to the Russian hybrid ports because they are used for station reboost and fluid transfer to the Russian segment. CST-100 and Dragon V2 will dock to the new NDS ports. Docking is a requirement for crew vehicles because they need to be able to undock autonomously in case of an evacuation, which is impossible with the CBM ports.

There is no need for a spacedock. It is much easier to build stuff on the ground with minimal orbital assembly than to build things from scratch in an orbital space dock. The whole point of the ISS is to perform experiments in microgravity. A centrifuge generates vibrations that would interfere with those experiments. - - - Updated - - - Running it as a museum would cost as much as maintaining its science activity. The ISS must be deorbited when it reaches its end of life, ie: when maintenance starts to become problematic. Most of its parts have a shelf life: seals, fluids, filters, pumps, motors, lubricants, solar panels, etc... You can't just shut it down and mothball it, because without maintenance and attitude control, systems are going to fail, its structure is going to fatigue, its orbit will degrade, and it will end up breaking up into debris and becoming a hazard.

The Shuttle used the Russian APAS system, because it had been contributed by the Russians for the Shuttle-Mir program as a leftover from Buran. Instead of refitting the Shuttle fleet, NASA continued to use APAS on the ISS. Note that Columbia never received a docking port, therefore even if she hadn't been destroyed, she couldn't have been used for ISS operations.

I don't see why that sounds unrealistic. You need 9km/s of dV to reach orbit. The job of the first stage is to get the rocket out of the atmosphere while adding as much dV as possible. 1 or 2km/s sounds realistic. The upper stage does the brunt of the acceleration work.

I don't see what the problem is. There is no difference in terms of Coriolis effects between a ring and a cylinder. The spacecraft only accelerates during a period at the beginning and end of the journey. I'm assuming that the action takes place during cruise mode, so there shouldn't be any propulsion events. Another design assumes a steady 1g acceleration during half of the flight, and a steady 1g deceleration for the other half. This gives you natural 1g gravity for the entire flight without rotation. It does require massive amounts of power though. In that case, just do like most science fiction writers do, and wave away reality when it bothers the plot. But if you want your spaceship to be a realistic design, no mechanical engineer would ever build one with ANY moving/rotating/unfolding parts that aren't absolutely necessary. They would design the ship specifically to minimize mechanical failures. In that case, you would have a rotating ship and an unpressurized rotating mast with the startracker sensors, it would be much easier than having a massive pressurized rotating joint that is bound to wear out after years of constant friction. But even then, a civilization that can build generation-ships surely has the means to use multiple sensors around the circumference of the ship to produce non-rotating imagery with computers.

Counter rotating rings are a recipe for disaster in terms of reliability and maintenance. As you demonstrate, it's more likely to break. It's much easier and cheaper to simply rotate the entire spacecraft.

Solids are used by the military because they have long duration storage and instant availability. Solids are used for civilian rockets because of the synergies with military rockets. Part of their cost is subsidized by military development, which makes them cheaper. It is also in the Government's interest to keep solid rocket manufacturers in business, for strategic reasons.

The Shuttle SRBs were jettisonned while there was still residual combustion. SRB don't just die down all at once. However, for a liquid engine, you would want to wait until the combustion is finished before separating.

Building and operating instruments is engineering too, and it's just as important, if not more, than the spacecraft bus. US instruments get rides on other countrys' spacecraft too. US spacecraft get launched by other countrys' rockets. It typically works in both ways through a mish-mash of barter agreements. International cooperation is made of barter agreements because national agencies don't want to send money to foreign corporations because their main purpose is to develop local jobs and national technology. They prefer to pay a domestic company to develop domestic technology that can be bartered against a service or a ride from another country.

SpaceX is NASA. Falcon was subsidized by NASA. The Merlin engine is based on a NASA reference design. Dragon is being paid for by NASA's CCDev program. Most of what SpaceX does is for NASA and there would be no SpaceX without NASA. I really wish the fanboys would stop the SpaceX-rah-rah cheering and opposing SpaceX and NASA as if they were competitors or opponents. SpaceX is mostly a NASA contractor, just like Boeing, ULA, and the rest of the aerospace industry. There is no such thing as "commercial space" without NASA, DoD, and other governments paying for infrastructure and development costs.

There is no habitat. No missions have been funded or even supported by Congress beyond EM-1 (unmanned circumlunar) in 2017 and EM-2 (manned circumlunar) un 2022. If there ever is a DSH, it will be either MPLM-based or a "skylab-type" converted upper stage. Centrifuges are off the cards because we simply don't know if they would be beneficial or detrimental and because they are not needed for the any foreseeable mission.

Pretty much all space exploration missions are international cooperations. The single-nation ones are the exception, not the rule.

SpaceX isn't going anywhere without NASA's money.

You forget that the aerospace industry in the US only exists because the Government pays for it through NASA and DoD. The commercial offerings are only possible because they are built upon a highly subsidized infrastructure. The Government does that because it creates highly qualified jobs and generates technology that benefits the country. The science and prestige objectives are secondary. Outsourcing the industry to foreign countries would be counter-productive on so many levels. Not only would you destroy domestic jobs, but you would also be exporting the technology that you spent decades building.

In a vacuum, exhaust gasses expand more laterally, because there is no air pressure to keep them in a nice pointy shape. So that first picture (as well as KSP) is inaccurate. This is why upper stage nozzles are much longer than first stage ones. Whether the plume is visible or not depends on the gas and the lighting. If light is not reflecting or shining through the particles, then it won't be very visible.

It was for heat radiation. Corrugated panels expose a larger surface.