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How did the Apollo Lunar Module ascent engine prevent gas bubbling through fuel?
As I understand it, in order to keep the lunar module ascent engine simple, instead of fuel and oxidant pumps, tanks of helium at pressure were used. This pressure was used to force the fuel and oxidant through the pipes to the engine, where they…
Flynn
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Why do the Russians use these fence-like interstage fairings?
When we look at various Russian rockets we often see a metal structure looking like a kind of garden fence separating some stages. To my knowledge, only the R7 family (Vostok, Voshkod, Soyuz) and N1 are (were) using it, but nobody else.
All other…
DarkDust
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What is the vapour/smoke that comes from a rocket before launch?
While a rocket is waiting on the platform during the final countdown, it often seems to have clouds of steam or something similar escaping from it.
Is this normal, and what are these clouds?
Rory Alsop
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Why did Apollo 11 need someone to stay behind in lunar orbit?
When Neil Armstrong and Buzz Aldrin descended to the moon in the Lunar Module, Michael Collins stayed up in lunar orbit in the Command Module.
Why did they need someone to stay behind?
At this point, rendezvous and docking with an unmanned…
Joe
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If we can get people to the moon and back, why are we so adamant that it's impossible to service James Webb at 4x that with a one way robotic vehicle?
Sources, including NASA and media, all emphasise that JWST at L2, is a million miles away, and therefore "if anything goes wrong, nothing can be done, it can't be serviced".
But over 50 years ago we could get a manned craft to 0.25M miles and back,…
Stilez
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How (the heck) did Lunokhod 2 drive, navigate and survive a ~40 kilometer drive over four months on the Moon using 1970's technology?
Mashable.com's Every rover, ranked by distance traveled on the moon and Mars; The 13 rovers, ranked. calls attention to this amazing feat, and a review of basic statistics and discussions on odometry are available.
Driving this far requires careful…
uhoh
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Can I see the ISS from the surface with the naked eye?
Can I see the International Space Station (ISS) from the surface with the naked eye? If yes, how can I determine that it really is the ISS?
Zoltán Schmidt
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Are there any weapons in space?
We can break this down into two categories:
For internal security purposes, does the ISS have any type of weapon on board?
For global security purposes, are there any orbiting weapons (that we know of)?
Obviously governments launch lots of…
Stu
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Is Jupiter bright enough to be seen in color by the naked eye from Jupiter orbit?
After seeing spectacular photographs of Jupiter, especially this one:
I wondered if this would be visible with the naked eye from Jupiter orbit? Is the sunlight at Jupiter bright enough to see this in color, or would we merely see a very dim, low…
Kaushik Ghose
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During the Space Shuttle Columbia Disaster of 2003, Why Did The Flight Director Say, "Lock the doors."?
Why does the NASA Flight Director say, "Lock the doors.", when realizing that disaster had struck for Space Shuttle Columbia, back in 2003?
Does he mean lock the doors on the space shuttle that's falling down, or does he mean lock the doors in the…
user42228
44
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2 answers
Why didn't the Space Shuttle bounce back into space as many times as possible so as to lose a lot of kinetic energy up there?
From this video, I got know that Space Shuttle did reentry around 5000 miles away from landing site. It's angle of attack is maintained around 40 degrees during re-entry. If it is more than that, it bounces back to space.
Why don't we let the…
SRD
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How did Apollo missions solve the cosmic radiation problem?
One of the major hurdles of space exploration is cosmic radiation. How did the Apollo missions solve the radiation problem?
NASA would have shielded the astronauts to some level by some material. How did they try to at least minimalise the effect?
r2_d2
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What is the difference between Cape Canaveral and Kennedy Space Center?
Cape Canaveral and Kennedy Space Center are both at pretty much the same location in Florida. I do not understand why they are referenced separately in media.
How much are they separate entities? Is there any significant difference between the two?…
JohnEye
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Did the Saturn V rocket have any purely aesthetic features that didn't serve an actual function?
The rocket itself is magnificent, yes, but with so many ins and outs to it, curious if the entire design was solely purpose built, or if there were features specifically for aesthetic purposes.
v15
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Which is closer to Mars, Earth or the Moon?
Which is closer to Mars, Earth or the Moon?
I'm writing a novel and I'm so grateful for the wealth of information. The only answers I find refer to Phobos and Demos Mars moons.
T. Constantine
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