35

You're right: this has issues. You can insert a station into a circular orbit halfway between Earth and Mars, but because this has an orbital period also in between those of Earth and Mars, your station won't be in a usable position most of the time. So you'd have to fill the orbit with several station to always have one reasonably close. The fuel is also ...


28

It turns out that yes, there are things you can do, but they depend on things other than the astronaut's body, and they will take a long time. Physics tells us that an object's translational momentum is constant unless acted upon by an external force. If the astronaut's net momentum with respect to the room is zero, there is nothing they can do to start ...


25

Fortunately, it turns out humans come with a nitrogen/CO₂ thruster built in... Assuming the room is filled with air, I reckon the best method is to use your breath. What you should do is, point your feet in the direction you want to go (there are quick standard techniques for this, like what cats do to land feet-down). Then breathe in deeply using your nose ...


15

Floating water (or other fluid) droplets cannot be returned to Earth without losing their form. Photo credit NASA


12

It's hard to guess what is in the mind of another contributor, but... Using a cycler model could involve a network of space ports, and the cycler would take the role of a "midway" space station (it taking care for the cargo for the portion of the journey between Earth and Mars) In Earth orbit, there would be a staging post or spaceport. Launch vehicles ...


8

tl;dr: Park your ISS-like space station above 700 km and there is a good chance it will only lose 100 m/s in 1,000 years due to atmospheric drag at least (and 2000 km for a million years). However, there are other problems This is a really interesting question! Just for example, the LAGEOS satellites are about 6,000 km above the Earth's surface and are ...


8

This question is far too broad to be answerable with enough detail, and it depends on whether you mean the absolute bare minimum or whether you mean "to perform a particular function". Let's assume it's the bare minimum, which I will assume to mean "people can go there in their own spacecraft, stay for a while, and then leave, all safely". This answer will ...


7

Here's a list of the main components of the ISS (source). Zarya Unity Module Zvezda Desinty Laboratory Module Harmony Module Columbus Orbital Facility Japanese Experiment Module Truss and Solar Panels However that's the ISS, in general, space stations have these components. Docking ports Habitat Module (Living quarters. (Sleep, eat, exercise, hygiene) ...


7

This is a strange question, but it is worth answering. The ultimate answer is: Space is hard. But let's unpack that. There were many, many factors that led to the various failures and accidents. Some of them were a simple lack of understanding during the design phase - space is hard, that's not a joke but a reality. Simply put, we don't understand how ...


6

Required even for short stays by humans: one or more pressurized compartment for the astronauts to work and live inside. This are often cylindrical modules that attach together to form the mechanical structure of the station. solar panels for electrical power thermal radiators to get rid of heat produced inside the station carbon dioxide removal from air ...


6

During the Apollo era (1967-1972), 4 NASA astronauts died during training or test flight. Those 4 brave people were the Apollo 1 crew, Gus Grissom, Ed White, and Roger B. Chaffee. The fourth astronaut was Clifton C. Williams who died flying a training jet. However no NASA astronaut died in spaceflight during the Apollo era. Unfortunately, there were ...


6

It appears to have actually been a pole, not a cord. Handrails and handholds, colored blue for quick identification, were located throughout Skylab. A removable, collapsible "fireman's pole" extending from the workshop hatch to the floor of the forward compartment provided a means of rapid movement. However, the astronauts soon found that they ...


5

Yes, there has been at least one color blind astronaut. Astronaut pilots cannot be color blind, but some color blindness is permitted with mission specialists. Roger Crouch is one such example, he flew on STS-83 and STS-94. There's a short article on it on NASA's web site. I don't know what kind of color blindness he has, I suspect if you have red/green ...


5

No. I can't find a NASA source, but I can find one from the Canadian Space Agency, whose astronauts have to ride on NASA missions and therefore would meet the same requirements. It specifically states "Applicants must not be colour blind"source.


4

Is a midspace space station between Earth and Mars practical? Here's a naive view: The problems with notions like a "halfway" station is that the locus of points halfway between Earth and Mars is probably a thick disk with an radius about equal to the average of the average of Earths and Mars orbital radius. Mars also has the second most eccentric orbit of ...


3

The ISS’s solar panels, radiator panels, robotic arms, and possibly the truss itself would collapse under their own weight if brought into earth gravity. These devices were assembled or deployed in microgravity. In the interest of minimizing mass, structural strength was designed to be sufficient only for the small forces and accelerations of space operation....


3

First, let's ask ourselves "why do orbits decay?". For multiple reasons. Atmospheric drag. Solar gravity acting on satellites. Solar activity Satellites in geostationary orbit can stay in orbit for billions of years, such as the EchoStar XVI which orbits around 35000 km above Earth. Safe from the atmosphere, far enough to not decay from solar flares, and ...


3

In this answer to What propulsion system would not pollute the surface when landing on a pristine celestial body? I ballpark estimated that the angular spread of an ion beam from an ion engine could be 1° or less based on plasma temperature. A small fraction of the ions passing nearest any acceleration grid wires might get deflected farther, but would be a ...


3

Classically at least, the conservation of angular momentum has never been known to fail. As long as everything on the station stays on the station, the total angular momentum of the whole thing will remain constant. People can jump up and down, move around, make lots of heat, all go to one side, or the middle, it doesn't matter. The angular momentum of a ...


2

This one is Jeffrey's fault. The human bladder can hold up to 600 mL, though people usually start to notice it at 150 mL. Urine has a similar density to non-man-made water - it can be more dense, but that's typically not the case when one has a full bladder. Using an approximate astronaut weight of 72 kilos (height from here, weight in the middle of a ...


2

A spherical spinning station faces a number of problems. First, different latitudes will have different amounts of centrifugal "gravity" (due to different radii to the central axis), which is fine under some scenarios but not at all helpful if you only care about the parts that are at your target acceleration and maybe a bit at free-fall in the middle (which ...


2

Would air circulate in a rotating station on its own? Short answer, no. Rigid body rotation of an air-filled station would result in a static and very very slight gradient in pressure (being highest at the point farthest from the center of rotation) but rotation alone wouldn't produce any forces that would sustain circulation. Friction would slow any ...


1

Following Organic Marble's spirit, I guess the thermal shields on the capsules will be destroyed when they are returned to earth. 100% sure there are a few of those up there right now.


1

For solar astronomy, this is already being done. The STEREO spacecraft for instance are in the same orbit as Earth, but one's ahead of Earth and the other one behind Earth so they can study the Sun from different angles. For radio astronomy, interferometry is a useful tool, but if you're going to launch a radio telescope you might as well position it ...


1

A rotating space station in a low Earth orbit (about 400 km) will gradually slow down. The drag caused by the non perfect vacuum not only lowers the orbit, it will also slow down rotation. But the circumferential speed of the space station is much lower than the orbital speed, so the rotation slow down will be very, very small. This is only true for a low ...


1

ISS is a lot bigger than MIR was. But it's total pressurized volume is only 930 cubic meters. Skylab volume was 335 cubic meter. Cost I think was 2.2 billion dollars in current values. Well... it was put in orbit in a SINGLE launch. That makes the most difference. ISS is less than 3 times the volume of MIR or Skylab. But it cost probably over 10 times the ...


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