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1500 questions
23
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3 answers
Can a single Soyuz return a crew of six back to Earth?
Let's say that the ISS has to be immediately evacuated and that one of the two Soyuz is broken.
Could the crew quickly remove "unnecessary weight" (seats maybe?) and fit six person to return back to Earth?
pastullo
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Why do the Mars rovers move so cautiously?
All the Mars rovers tend to move very slowly. For example, Curiosity moves at an average speed of 30 metres per hour and a maximum speed of 90 metres per hour. Why is this so? Is it because of safety reasons? Does the time lag between Earth and Mars…
coleopterist
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23
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Could the shuttle's SRB alone reach orbit?
If one equipped the SRB like the ones used with the Shuttles with minimal attitude control systems and launched it as a standalone rocket with no payload - what speed would it reach? Would it be capable of entering the Low Earth Orbit?
More…
SF.
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How intrusive was the Apollo Master Alarm system?
During the Apollo 11 landing, a misconfiguration caused the guidance computer to activate the 1201 and 1202 program alarms, signifying that the computer was overloaded and dropping low-priority tasks. This was connected to the master alarm system to…
Russell Borogove
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23
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5 answers
Why won't JWST deploy in LEO where it is potentially serviceable?
The James Webb Space Telescope will deploy (unfold mechanically) while on the way to L2. Couldn't it do so in LEO, where it is potentially serviceable? Starliner CST-100 and Dragon are planned to soon allow affordable crewed missions to LEO, and…
LocalFluff
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23
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3 answers
How often are ISS computers (MDMs) replaced?
The electronic "heart" of the International Space Station are the Multiplexers-Demultiplexers (MDMs) located within & outside the pressurized modules.
How often are they replaced? (An ideal answer would be based on actual statistics and would,…
Deer Hunter
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23
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Maximum survivable atmospheric pressure
Given a similar mix of gases to those in our Earth's atmosphere, what is the upper limit of survivable atmospheric pressure for a human?
Could a human survive higher pressures with a gas mix unlike those on Earth?
What about mixes such as Titan or…
Ezra Bailey
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How does SpaceX plan to achieve reusability of the Falcon 9 *second* stage?
Update 08 April 2017: Elon Musk tweeted an indication that they're revisiting the possibility of second stage recovery, so this question is again relevant, and the details of the new solution may be different from the old.
Fairing is ~$5M, but that…
Russell Borogove
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23
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1 answer
Were the Apollo 11 astronauts aware of any parts of the Luna 15 mission?
I just learned today about the Luna 15 mission which was a Soviet attempt to land an unmanned probe on the moon which coincided with the successful Apollo 11 mission.
Were the Apollo 11 astronauts aware in any way of the the Luna 15…
Max Q Lagrange
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23
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Voyager 3: what would have been its mission, and why was it canceled?
In researching the answer to this recent question, I came across some information that was new to me. A third Voyager mission was planned, and then canceled. Apparently, Voyager 3 was cannibalized during construction:
I am currently reading the…
Hobbes
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23
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1 answer
What is the South Atlantic Anomaly, and what can I do to protect satellites from it?
I've heard of something called the South Atlantic Anomaly (SAA), which seems to have a lot of Low Earth Orbit Satellite Operators quite worried. What is it, and how can I protect my spacecraft against it?
PearsonArtPhoto
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What coordinate system is used in space for navigation?
On Earth is possible to define the position of something using WGS, and the same system is used for navigation. What is used in space instead? Are different systems used for Earth-orbiting objects (the ISS for example) as opposed to objects beyond…
user55
22
votes
4 answers
Were the Apollo lunar activities observed from Earth?
I understand that all manned landings on the Moon were on the near side, so technically they could be visible from Earth.
Was it possible to observe landings and/or extravehicular activities (EVAs) with Earth-based telescopes? If not, why?
Cedric H.
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22
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3 answers
Has any CubeSat flown with an active propulsion system?
CubeSats are small, but so are some propulsion systems (cold gas thrusters, for instance, really aren't too complex and can be low volume/mass). Has any CubeSat actually flown with its own propulsion system? If so, what were the results?
user29
22
votes
2 answers
Why were Space Shuttle astronauts able to walk off the orbiter?
I am watching loads of ISS related videos and there is one detail I recently noticed;
At the time, when Space Shuttles were still in operation and visiting ISS, when astronauts returned home, they were able to walk off the orbiter as it landed to a…
Pavel Janicek
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