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47
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2 answers
Why did the JWST solar array deploy early?
According to NASA's Deployment Explorer tool, the solar array was expected to deploy at T+33 minutes.
In the NASA livestream, the solar array deploys at T+29:08 (the clock isn't on stream at that moment, but at T+27:08 is exactly 2 minutes before…
fyrepenguin
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47
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Why Mars instead of a space station?
Elon Musk has made very clear that his goal is a colony on Mars. That doesn't seem ideal to me at all. Certainly some people will be happy to live on Mars for the rest of their lives, but they will not experience full gravity or fresh air, having to…
Gene McCulley
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47
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11 answers
Finned heatsinks in space
Most heat radiators in space are flat surfaces. In a sense they are single fin radiators. Has anyone studied the used of multi-finned radiators in space (the vacuum of space, not inside a spacecraft)? Any papers on this?
I think it's easy to…
martin's
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4 answers
Why does NASA publish all the results/data it gets?
I was curious about why NASA publishes all the results/data from its operations. Does the USA have a law that mandates it or is it a voluntary contribution to the world?
PhoneixS
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47
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6 answers
Could the shuttle wait out the whole burn of SRBs on launchpad in case of a problem on launch?
Somewhere on this site I read that in NASA, the rocket leaves the launchpad (through release of explosive bolts) only after the engines have attained full power.
Assuming in the scarce seconds between SRB ignition and launch a critical failure…
SF.
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47
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8 answers
What would be the (most difficult) challenge to make a 10,000 year satellite?
Update: Bezos' recent Tweeted update on the 10,000 year clock. Also see The Verge's Construction begins on Jeff Bezos’ $42 million 10,000-year clock
The discussions associated with the question Can an artificial satellite stay in orbit forever? and…
uhoh
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47
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4 answers
How is a rocket stabilized during the initial, slow speed, portion of launch?
Let's say we're at T+0, just as the rocket starts to move, what keeps it upright as it clears the tower and gains speed?
nexus_2006
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3 answers
Did the Galileo spacecraft cause a "blotch" on Jupiter after it crashed?
There's this interesting story: Did NASA Accidentally “Nuke” Jupiter?
Long story short:
On September 21, 2003 Galileo is deorbited in order to prevent eventuality of contamination of Europa. It descends into Jupiter atmosphere.
October 19, 2003 an…
SF.
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6 answers
Would it be easier to put humans on Venus rather than Mars?
With all the speculation of manned missions to Mars, there is very little talk of a manned mission to Venus (whose orbit is closer to the orbit of Earth than mars is). That being said, would it be easier to put humans on Venus? If so, how & why?
jw01
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Why were the Space Shuttle's main engines placed on the orbiter?
Since the main engines can't be used after external tank separation, what's the reason for having the engines on the orbiter rather than just building a third rocket on the stack instead of the external tank?
It seems that not having to deal with…
Brad
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7 answers
Why did Saturn V not head straight to the moon?
This may seem a naive question, but as I understand it one of the reasons for the enormous energy expended by rockets is the extremely high speed (around 28,000kph) you need to achieve a stable orbit and avoid falling back to Earth.
The Saturn V…
Party Ark
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1 answer
Why A=2 and B=1 in the call signs for Spirit and Opportunity?
The Martian rover Spirit held the call signs MER-A and MER-2. Opportunity was called MER-B and MER-1. The assignment A=2 seems backwards; logic would suggest A=1. Why is this so?
Based on comments in a previous question, answered by @MarkAdler. …
DrSheldon
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46
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2 answers
Using ozone as oxidizer
The bond energy of $O_2$ is 498kJ/mol. The bond energy of $O_3$ is 364kJ/mol.
That means the energy to break up the particles into 3 moles of monoatomic oxygen (which then binds with fuel to release energy) is 747kJ for $O_2$ and only 364kJ for…
SF.
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Would it have been possible to have sent the Space Shuttle around the Moon?
I'm curious about whether or not the Space Shuttle could have been used as a lunar orbit vehicle - basically, would have it been technically capable of getting to the Moon, entering orbit, then leaving orbit?
My reasoning is that since the Shuttle…
user12
46
votes
1 answer
Why vent $CO_2$ and $H_2$ waste products to space on ISS?
In this answer, it's mentioned that waste $CO_2$ and $H_2$ from the Environmental Control and Life Support Systems (ECLSS) are vented into space from ISS.
Are there no other uses for this material now or possibly in the future?
More generally,…
Steve
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