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1500 questions
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Passive attitude stabilization with magnets - are there studies based on actual flight data?
Specifically with the small satellite and cubesat people, there is an rather 'old' idea around: Passive attitude stabilization based on permanent magnets.
Schematic of the Earth magnetic field lines and camera orientation throughout polar orbit…
s-m-e
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Why wasn't the Apollo 13 Service Module jettisoned until hours before reentry?
Looking at the Apollo 13 mission timeline within three hours after the explosion of O2 tank two all oxygen in the SPS was completely depleted. Fuel cells #1 and #3 were off line. CM had even started to cannibalize its reentry batteries, before it…
djf
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What payload was expected for the 2018 Mars Dragon flight ("Red Dragon")
SpaceX has long been planning to use Dragon capsules to carry objects anywhere in the Solar System. They have officially announced a 2018 launch to Mars. Specifically, the launch window is April-May time frame, about 2 years from how. What, if any,…
PearsonArtPhoto
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Is the overall mortality rate for being in a spacecraft in space or bound for space about 4%?
I just read this answer in astronomy.stackexchange, where a sobering point was made that the overall to-date chance of losing ones life in a spacecraft is about 4%.
While I don't want to dwell on that, is it roughly correct? What are the numerator…
uhoh
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Did the Mars rovers actually confirm the gravity of Mars?
For years the theoretical calculated gravity of Mars has proliferated science texts and Internet documentation - but did the rover actually do a test to confirm the theoretical gravity is truly equal to the actual measured gravity?
Chris
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What was the space-worthiness determination procedure for STS-1?
I am specifically interested in on-ground tests that were conducted after the full shuttle was pieced together (orbiter, tank, engine, boosters) for the first time (before STS-1).
Of course the number of individual tests may have been quite large,…
user40
19
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1 answer
What space applications, projects and agencies are using the Ada programming language?
The answer to this question mentions the use of Ada-programmed applications on the ISS.
Ada was developed for the US DoD to replace a plethora of computer languages (some 465), for mission-critical applications. It has a strong ability for fault…
My Other Head
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Are Armageddon's simultaneous shuttle launches feasible?
In Armageddon, two space shuttles launch from adjacent pads mere seconds after one another.
This seems highly implausible for several reasons:
Pressure, heat, vibration and debris from the first launch might damage the second shuttle's launch…
Elle Fie
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How to calculate delta-v required for a planet-to-planet Hohmann transfer?
How do you calculate the delta-v required to do a Hohmann transfer from a circular orbit around one body to a circular orbit around another?
I'm assuming you'd need to know the masses of the two bodies, and the mass of whatever they're orbiting…
Joe
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Was the third shuttle engine any different from the others?
The space shuttle used three SSME, organized in a triangle with two next to each other closest to the external tank, and one on top of those. I am pretty sure the first two engines were close to identical, in order to maintain symmetry. But the…
SE - stop firing the good guys
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Would my weight be constant on Pluto?
Since Pluto and Charon have distinct orbits around their barycenter (located approximately 960 km above Pluto's surface), the centripedal acceleration must be different on the outer hemisphere of Pluto (in relation to the barycenter).
Does that mean…
mhbuur
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What prompted Lovell on Apollo 8 to announce "there is a Santa Claus"?
On Apollo 8, following the first trans-Earth injection, when the crew came back into contact with Houston, Lovell said: "Please be informed there is a Santa Claus." (Transcript)
Given that Apollo 8 had already been in contact with ground through…
called2voyage
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Would it be possible to get back to Earth from the ISS without any ground support?
In the TV show Last Man On Earth we follow a small group of immune survivors after an apocalyptic plague has essentially wiped out humanity. It is revealed that a single astronaut on the ISS has also survived albeit he is not very hopeful about his…
Brian Lynch
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What would have happened if only one Space Shuttle SRB ignited?
The ignite command for the Solid Rocket Boosters (SRB) would not be issued unless all three Space Shuttle Main Engines (SSME) were at least 90% of thrust. The launch would have been aborted if one or more of the SSMEs failed to reach required…
poke
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Apollo communication between the Earth and Moon
How was it possible for astronauts to send back tv/radio signals to earth from the moon? I have just been teaching my son about waves behavior and understand that radio waves are reflected back to earth from the ionosphere. As far as I know…
slick
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