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Why is it not possible to deorbit in a shallow glidepath?
The fiery re-entry of spacecraft has been a staple of spaceflight since the beginning, making ablative heat shielding a necessary component of any craft wishing to return to Earth intact. This is the result of the shockwave caused by the high-speed…
Jerard Puckett
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Is potable water in the American & Russian segments still stored separately?
This article writes to say
An interesting fact is that the Russian and American segment water supplies can’t be mixed. The U.S. water uses iodine for bacteria control, while the Russian water uses silver. If these substances mix, a silver-iodine…
Everyone
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What software language was used to program the martian rovers Spirit, Opportunity and Curiosity?
What software language was used to program the martian rovers Spirit, Opportunity and Curiosity?
Also, how many engineers were involved in writing the software for the rovers?
Flea
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Why weren't Gemini capsules given names?
Mercury capsules had names (e.g. Liberty Bell).
Apollo command modules had names (e.g. Columbia).
Apollo lunar modules had names (e.g. Challenger).
Space Shuttle orbiters had names (e.g. Columbia and Challenger).
Why didn't the Gemini capsules have…
DrSheldon
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After the loss of Challenger, why weren’t Galileo and Ulysses launched by Centaurs on expendable boosters?
The Centaur upper stage, the first hydrolox rocket stage ever flown and (in its highly-evolved forms) still one of the most-used, as well as one of the highest-performance (if not the highest-performance) upper stages available, was used from the…
Vikki
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Why not send Voyager 3 and 4 following up the paths taken by Voyager 1 and 2 to re-transmit signals of later as they fly away from Earth?
Voyager 1 and Voyager 2 spacecrafts are on their journey out of solar system. They collected so much of important data that helped us understand our solar system. As these spacecrafts moving out of solar system they are still transmitting the…
Xinus
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Does it take more energy to get to Venus or to Mars?
Let's assume we use the ideal positions of those planets relative to Earth for launch. And let's assume the spacecraft is launched from the same place on Earth. Also let's assume the goal is to get the same mass of payload to those planets, meaning…
stackzebra
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What is the cost estimate for a manned Mars mission?
I am looking for a cost estimate for a manned (return) mission to Mars. There is a similar question asking for the cost of the Mars One proposal, but I would be happy with a cost estimate for any type of human mission to mars. I need something…
Jakob
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Could Hubble observe the night side of the Moon?
IIUC the Hubble space telescope cannot observe the Sun lit side of the Moon. And Hubble is never pointed closer than 90 degrees towards the Sun. But this still allows for observing the night side of the Moon during phases between full moon and half…
LocalFluff
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How best to maneuver inside a large room within a space station using only arm and leg motion?
Imagine the following thought experiment:
An astronaut is inside an extremely large room within a space station. Suppose that she, for whatever reason, is initially at a zero velocity with respect to the room and her position is at the center of…
Paul
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Is it bad if hydrazine freezes on a spacecraft? Is it always kept as liquid, or can it be safely allowed to freeze and then thawed when needed?
After having read this answer I wondered what happens if hydrazine freezes.
It looks like it is "normal" and not like water, in the sense that it contracts when freezing, unlike water which expands and can cause mechanical…
uhoh
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Are images of exoplanets' surfaces technically possible?
While already even taking an image of an extra solar planet sounds like science fiction to me, is it technically possible by what we know now to take also more detailed images of extraterrestrial planet surfaces?
For simplicity, let's take…
J. Doe
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Did NASA's Borg Collective-designed antennas work? Have similar designs ever been used in spacecraft beyond testing?
This interesting answer to the question Do antenna farms on spacecraft make any sense or are they purely aesthetic? in Worldbuilding SE links to the NASA Ames page 'Borg' Computer Collective Designs NASA Space Antenna. The clever title refers to a…
uhoh
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What eliminates the velocity when occupants return from ISS to earth, and how much?
The ISS has an orbital velocity of ~28000 km/h; the velocity $v$ relative to the landing site of the descent module is probably even higher than that most of the time. Once the occupants have landed, their velocity relative to the landing site is…
Alexander Klauer
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How are fuel tanks filled with cryogenic hydrogen?
Cryogenic hydrogen can react with the atmospheric Oxygen to produce an explosion:
as well as being cold enough to liquefy (and possibly solidify) atmospheric oxygen, which can be an explosion hazard.
If we start pumping fuel in when the tanks are…
Hash
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