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1500 questions
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Is there any non-rocket spacelaunch concept within reach of current material science and technology?
Suppose for a moment that cost would be no issue (and noone brought pruning shears) - could we build any of the non-rocket spacelaunch systems from earth listed here or elsewhere? Which one is the least unfeasable given current technology?
mart
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Has the Earth's red atmosphere rim ever been photographed?
In the Wikipedia article on Lunar eclipse there's given an image of how the Earth would look from the eclipsed Moon:
This is obviously a schematic drawing. So I wonder, has the Earth ever been actually photographed from such a position where both…
Ruslan
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How does SpaceX ignite their engines?
Based on the aborted launch on Thanksgiving 2013 of the first Falcon 9 v1.1 from Florida, we know that an issue occurred where oxygen got into the ground based TEA-TEB sources.
I understand that TEA-TEB are pyrophoric , which means they combust on…
geoffc
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Will SpaceX delay launches, if the landing site weather is unacceptable?
With the initial landing attempts, it was not a big deal, twas all an experiment and they only reused Block 1-4 boosters once at best. So holding a launch because of weather at the landing site downrange on the barge (LZ-1, being 10-20 miles from…
geoffc
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Why don't unmanned launch vehicles include launch escape system for payload?
Mention of Launch Escape System (LES) brings to mind images of the crew on board a spacecraft ejecting at launch; the crew being the most valuable cargo on board.
Launch vehicles may also be unmanned, e.g. PSLV/GSLV, Ariane, etc. In this case, the…
Everyone
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What is the rarest launch window?
What situation would make a launch window rare? What is the rarest known launch window?
Muze
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Rock flipping operation
After the recent announcement of complex organics being found on Mars within the curiosity rover's meager 5cm drill depth, I had an idea about artificially increasing it:
Is curiosity rover's arm strong enough that it would be able to flip a small…
Dragongeek
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What was the reason to use different fuel for the Apollo Service Module propulsion system and reaction control system?
The Apollo Lunar Module LM used the same fuel/oxidizer combination (Aerozine 50 fuel / nitrogen tetroxide (N2O4) oxidizer) for both descent and ascent stage engines and reaction control system. This combination was also used for the engine of the…
Uwe
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What artificial satellite has the farthest orbit around the Earth?
What is the furthest Earth orbiting satellite?
What is its speed and purpose?
Muze
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Why is Curiosity not heading for Peace Vallis?
For over 5 years Curiosity has been successfully searching for many signs that water was once present at Gale crater. Its geology is notable for containing both clays and sulfate minerals that may preserve signs of past life.
An unusual feature of…
Cornelis
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Do the solid rocket boosters of the Shuttle and SLS have a self-destruct system and was it activated during the Challenger disaster?
Videos of the Challenger shuttle explosion show both solid boosters speeding on after the main tank detonated. Were they eventually self-destructed by the ground control, or why not, and why not immediately? Where and how did they land?
Same solid…
LocalFluff
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Ariane 4: shroud around stage?
In this image of the Ariane 4, you can see a blue shroud around the second stage.
At least I think it's a shroud. It is present in many photos of Ariane 4 launches, but the drawings I've seen omit it. What is the purpose of this object?
Hobbes
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Where were the various Apollo Lunar Modules (LMs) discarded?
The LEM was comprised of an ascent, and a descent stage. Whilst the descent stage was in most cases left behind on Luna, the ascent stage ferried the astronauts upstairs to the CSM. Where are these vehicles now? Did they crash into the Earth/Moon,…
PearsonArtPhoto
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If Starman is heading to Mars, why is he still spinning so we see the earth?
If Starman is heading to Mars, why is he still spinning so we see the earth?
Shouldn't he always be pointing away from the earth?
v15
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How well would a broken bone heal in zero gravity?
We know that being in space has negative effects on bones. If you had a broken bone is space would it heal ok? Has there ever been a broken bone healed in space? Other then Spaceflight osteopenia would there be any concerns like the bone not…
James Jenkins
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