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1500 questions
19
votes
1 answer
Why was TESS' launch window open for only 40 seconds per day?
The BBC news podcast Science in Action episode New Planet Hunting Mission covers the upcoming TESS mission between 01:00 and 07:15 with Sara Seager, TESS deputy director of science, Massachusetts Institute of Technology, Cambridge,…
uhoh
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19
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3 answers
How close is the ISS to a closed system, in terms of carbon, hydrogen, and oxygen?
I found this diagram of the ISS ECLSS material flow and noticed the $CO_2$ being vented off the station.
source
Now, I understand this is outdated since they added a Sabatier reaction system to combine the $CO_2$ from the atmosphere and $H_2$…
Nick S
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19
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7 answers
Space Shuttle range safety system - Why is there a caution light?
Why did the Space Shuttle have an indicator to alert the crew to the arming of the range safety destruct system? Quoting from here:
The first message, called arm, allows the onboard logic to enable a
destruct and illuminates a light on the flight…
MattyZ
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19
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1 answer
Why are three cosmonauts required to move a Soyuz?
The opening paragraph of this article caught my eye*:
Three space station crew members put on spacesuits and boarded their Soyuz spacecraft Friday for a short trip to relocate the capsule to a new docking port on the orbiting outpost, clearing the…
user12
19
votes
4 answers
Why are the bottom of most stages flat?
When looking for rocket engine images, I noticed that the bottom of the stages are almost flat. That does not seem aerodynamic. I understand this is not a primary concern for upper stages (mainly operating into the vacuum of space) but it seems…
Manu H
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19
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3 answers
Would temperatures be more stable under the surface of Mercury?
Mercury, being right around than 55,000,000 km away from the Sun, gets hot. As in very hot - 700 °K hot (426 °C and 800 °F). Not a place you would want to live.
On the flip side, the side of Mercury not facing the Sun tends to be very cold -…
user12
19
votes
1 answer
If colonists burrowed far enough under the ice on Ganymede or Europa, would the ice provide adequate protection for them from Jupiter's radiation?
This is a hypothetical question I'm asking as a SF writer, and the time setting would be approximately 2,250 AD.
Mike Ackerman
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19
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1 answer
How much fuel was used for a Space Shuttle launch?
Many of us have watched the launch of a Space Shuttle space ship, I think: a giant red rocket, some smaller, and the way smaller space ship on the red one.
It reaches Mach 23 to be able to leave Earth. But what's the amount of fuel that is used…
Zoltán Schmidt
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19
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9 answers
Was the side booster footage from the same camera during the Falcon Heavy test flight stream?
Chat has once again led me to ask a question.
Geoffc suggest that the "two bottom feeds were from the same camera" as they aimed at the same landing site. I then started to collect some images to see if they were indeed identical (listed…
Edlothiad
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19
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2 answers
What was the outcome of the launch of ZUMA by SpaceX, to the best of the public's knowledge?
Now, I realise this question is inherently unanswerable due to the classified nature of the mission, and speculation is also not desirable, but that's okay — because we can at least assemble official sources into something that resembles the most up…
marked-down
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19
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1 answer
Why would extra fuel be needed to de-orbit the ISS (if it comes to that)?
The BBC article The Astronaut Fighting to Save our Home in Space discusses “experienced astronaut, and astrophysicist Dr Michael Foale”'s exciting career aboard the Space Shuttle, Soyuz, Mir, and ISS, and now current efforts to find future backers…
uhoh
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19
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2 answers
Was LC39A built with a rocket much larger than the Saturn V in mind?
The interesting question What are the most difficult challenges SpaceX will face getting astronauts to Mars by about 2025? links to Elon Musk's position paper Making Humans a Multi-Planetary Species which can be found (in both HTML and PDF formats)…
uhoh
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19
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5 answers
Would Luna 15 have been visible to any of the members of the Apollo 11 crew?
According to Wikipedia, Luna 15 crashed a few hours before Eagle lifted off from the moon, and since it crashed North-east of the landing site, it must have overflown them. Would any of the crew have been able to see Luna 15, perhaps the deorbit…
drewcassidy
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19
votes
2 answers
How deep is the force well of L4 and L5 Lagrangian Points of Earth-Sun set?
The Lagrangian Points are points in space, where the combination of gravitational pull of a set of two bodies and the centripetal force of orbiting one of them add up to zero. The special property of $L_4$ and $L_5$ points - in Earth-Sun system,…
SF.
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19
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1 answer
What made the Earth appear to be flat during the recent SpaceX launch?
During the recent SpaceX CRS-12 launch which was broadcast live on YouTube, it appeared at one point as if the horizon of the earth was completely flat.
What caused this to happen?
Tyler Faile
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