I will briefly list here some capsules which are being used for space station freight, and aren’t intended to carry astronauts: Progress (Прогресс) — Russia, 1978: Basically a Soyuz with all the unnecessary bits stripped out, this had already been supplying Russian space stations for decades before the ISS was put together. Over 150 of these have been launched. Early versions had a heat shield but nowadays that’s omitted. It is capable of returning very small payloads to Earth with a mini-capsule that it ejects. The service module has a pair of solar panel wings. Automated Transfer Vehicle — EU, 2008: This large expendable cargo carrier is currently on hiatus due to its high cost, but there’s talk of bringing it back, and maybe giving it some reusability. It’s a question of whether other nations can get the EU to do more, or whether they can get away with substitute contributions. The ATV (which originally stood for Ariane Transfer Vehicle) was made primarily by Airbus and flown on an Ariane 5, and they did get it officially human-rated, though they never fitted it for crewed use, or even for returning to the ground. It not only lifted plenty of supplies — about twice as much per load as lesser cargo craft — but its engine was also used to boost the space station, counteracting its orbital decay. To do this, it docks to the station’s back end, using a Russian docking port which is incompatible with those on the American end, which most of these other vessels use. The ESA flew several of these as their contribution to keeping the ISS running, with each one named after a historical European associated with space, such as Jules Verne and Johannes Kepler. Now its back end is being repurposed as the service module for Orion, this being one of the substitute contributions they prefer to make in lieu of further flights. But the shuttle engine was not part of the original ATV design; it just had four tiny nozzles. And they’re still there in the Orion version — in fact, there are now eight of them. I don’t know how they crammed all these engines into there; it’s not like there was a hollow center like in the Starliner service module. It has four skinny solar panel wings, giving it a look reminiscent of a Star Wars X-Wing. The ATV may return in a new form called ATV-X, which will service not the ISS but the Lunar Orbital Platform-Gateway. H-II Transfer Vehicle, a.k.a. Kōnotori (鸛 / こうのとり) — Japan: 2009: An even larger cylinder (10 meters long) which includes an integrated service module, this flies on an H-IIB. In fact, it’s the whole reason the H-IIB was built — the H-IIA couldn’t lift it. Its not reusable and cannot return cargo to Earth, but they are working on a replacement that can, called the HTV-R, which in turn would be followed up by a crewed capsule. These would be three part designs, with a cone, a large unpressurized trunk section, and a small service module. The cone is intended to have 15 cubic meters of pressurized space. For large loads, most bulk cargo would have to go in the trunk. This isn’t as bad as it sounds: despite its monolithic cylindrical shape, most of the current HTV is already unpressurized. A large hatch allows the Canadarm to reach inside this part. Solar cells cover the exterior on one side: no wings stick out. Before the HTV-R they will first fly a minor upgrade called the HTV-X, atop an H-III. (“Kōnotori” is a species of stork.) Dragon — USA, 2012: SpaceX’s original freight capsule was basically just a development prototype for their crewed version, the Dragon 2, but it’s done quite well at making deliveries, and it is fully reusable except for the trunk. Being much simpler than the crewed craft, it weighs barely over four tons dry. They stopped making more of these a couple of years before the Dragon 2 was ready, finishing the craft’s remaining jobs with reused capsules. The trunk is often left mostly empty; when it separates from the second stage, you can look right up into it. The original made its last flight in 2020. From now on they will deliver cargo in seatless Dragon 2 capsules, though these can’t deliver large interior fittings as the docking hatch is quite a bit narrower than the berthing port used by the original Dragon was. Cygnus — USA, 2013: This was from Orbital ATK, and now from Northrop after the acquisition. It can launch on either their Antares or an Atlas, with the latter allowing a heavier load. Comes in two sizes, short and stretched, with the latter being fairly substantial in size. The shape is a corrugated cylinder, like a can of beans. Actually, Northrop doesn’t even build the can, only its little service module. The can is built by Thales Alenia Space in Italy. It has no reusability. Each one gets named after a famous astronaut of the past. It has two circular solar panels that unfold like fans. This may be entering a second role in the future: a combined proposal for the lander part of the Artemis program has been put forth in which Blue Origin would provide the “Blue Moon” platform to land stuff on the moon, Lockheed Martin develops the crewed craft which comes back up again, and the craft which carries them and their supplies to lunar orbit, the so-called Transfer Element, is basically a Cygnus with no pressure can. This proposal has won some strong funding, but it is unpopular among industry watchers because the Blue Moon lander and the Transfer Element are both expendable, making it difficult to perform repeated visits to the lunar surface. It appears that with this proposal failing to win, the companies which bodged it together will now be going their separate ways, each with their own proposals. Tianzhou (天舟) — China, 2017: This made only one flight before their space station went up in 2021, in which it practiced docking repeatedly with their Tiangong 1 orbital laboratory testbed, and pumped fuel across the connection. The two are variations of the same design. Now the successor Tianzhou 2 model will supply the new Chinese space station. It has the usual cylindrical cargo area up front, and a service module which is long and narrow, with two large solar panel wings. It can haul 6.5 tons, and is not reusable. It sounds like the partition between pressurized and unpressurized cargo space can be adjusted from one mission to the next. Dragon XL — USA, 2024?: After saying that they would do no more development on the Dragon line of spacecraft, with all future work going into Starship, SpaceX reversed itself and announced that they would build a new cargo capsule for NASA called Dragon XL, to deliver freight to the Lunar Orbital Platform-Gateway. Launched on a Falcon Heavy, it would carry five tons or more of pressurized and unpressurized cargo to the LOP-G, with no return to Earth. As sketched out so far, it’s a big cylinder, with a hatch on the front and a trunk with folding solar panel wings in the back, like the original Dragon and unlike the Dragon 2. It may have no propulsion other than Draco RCS thrusters — we don’t know yet. It will go up inside a regular Falcon fairing, maybe oriented hatch end down, and will not return to Earth. But maybe this won’t be built — NASA may be looking for a way to do this job with Starship instead, or at least is asking SpaceX if that’s what they’d rather try. But Starship may not be safe to attach to the Gateway as it’s so heavy, and may not be capable of staying parked there for months, as is normal practice with any other cargo vessel, due to its use of entirely cryogenic propellants. Finally I have to mention the X-37B — USA, 2010: this is a small (5 ton) reusable spaceplane owned by the US Air Force. It resembles the Dream Chaser except it’s not nearly as pretty, and is unmanned. Like a miniature space shuttle, this has cargo bay doors on its back. It performs secret missions of long duration, like eight months at the shortest, and not much else is known about it. The Air Force’s official position is that it’s just a testbed for new technology and a platform for zero gravity experiments. It has a single rocket nozzle on the back end, which apparently reacts kerosene with peroxide — a fuel combination which, like hypergolics, can be stored for a long time without refrigeration. On its fourth flight they added an experimental ion engine, for orbital maneuvering on those long flights. SpaceX got to launch the fifth one. The other flights were on Atlases, including the most recent one. The cargo bay is about 1.2 meters in diameter and just 2.1 meters long, and it has deployable solar panels. The Air Force has two of these spaceplanes but they don’t put them both up at the same time. Boeing said they were thinking about building an X-37C, which looks very similar but is quite a bit bigger, and would be able to carry passengers in a cargo capsule. But nothing new has been heard since they announced the idea back in 2011. Meanwhile, China has been working on a military spaceplane which appears to be more or less an imitation of the X-37B. They may be calling it the Shenlong Space Plane (神龙/Shénlóng is usually translated as “divine dragon”, but nowadays you might as well just say “space dragon”). They’ve been working on it for several years, and first sent a small test version to orbit in 2020 (suborbital tests date back to 2011). They’ve also announced that they’re also soon going to build a much bigger plane, possibly called Tengyun, for suborbital flights with passengers. We don’t really have to concern ourselves with that one. So it sounds like it’s a bigger, badder SpaceShipTwo... but they apparently intend to make it a lot more practical, as a means of quick intercontinental transportation. The European Space Agency, having dropped their plans for the Hermes spaceplane, are now building their own X-37B-like drone. They call it Space RIDER, which stands for Reusable Integrated Demonstrator for Europe Return. It looks more like a plastic bottle of kombucha than a plane, with hardly any control surfaces. It’s almost a pure lifting body. It’s quite petite, weighing only about three tons. This wingless shape is good for reentry but poor for runways, so at landing time it will deploy a parafoil. With sufficiently smart control of that foil, it could land on a very short runway without needing wheels. It will launch on a little Vega-C. Its developers hope to parlay this into a large crewed version, but nobody is funding that yet.