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Elon Musk's ITS Travel Time to Mars Estimate
The average travel time to Mars has been quoted to be around nine months (~ 270 days). This assumes current propulsion methods and when Mars and Earth are near each other.
Musk has been quoted to say that his ITS space rocket system could make it to…
FontFamily
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Why did Cassini require so much more power than other probes?
Inspired by the comment by Nick S on this answer by Organic Marble, what made Cassini require so much power?
An excerpt from the aforementioned answer:
The flight units used by mission, with power levels at launch, were:
Galileo: Flight Units 1…
fyrepenguin
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Why are there four RTGs in a row sitting in this room? What are they waiting for? Were they built together and stored for separate launches?
The extremely cool NASA JPL video Triumph at Saturn (Part I) is really worth a watch and/or listen.
At about 17:40 it discusses Cassini's RTG and at 18:36 there is a shot of four RTGs in a row being checked for radiation levels.
RTGs have been in…
uhoh
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When burns are made during inefficient parts of the orbit, where does the lost energy go?
Any Kerbal Space Program player will know that burns prograde and retrograde to the velocity vector are most efficient closest to the body being orbited, while burns normal and anti-normal are most efficient furthest from the body being orbited,…
TheEnvironmentalist
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Can we write with chalk on blackboard in space?
There was an ongoing discussion on how fisher pen was invented independently for safer writing method.
I was just wondering weather we can use chalk and blackboard in space?
Also if there are challenges in making regular use of it, what are the…
Talk is Cheap Show me Code
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Why does the Soyuz cover its main engine?
As seen in Gravity, and also in this youtube video:
, the Soyuz main engine is covered by a metal plate that it mechanically moved out of the way before firing. What is the function of this covering?
Nickolai
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Why doesn't the ISS orient itself to the Earth's magnetic field like a compass needle?
I was watching this video of a magnet aboard the ISS floating freely. When the person lets go of the magnet, it behaves like a compass needle and immediately orients itself to the magnetic field of the earth.
Why doesn't the entire ISS (or any…
Wyck
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How much UV radiation will Mars inhabitants receive?
I have a new weather station for my home, and it included a UV radiation monitor. But I then thought, “What’s the UV radiation levels on Mars? How much higher is it than Earth?” I tried searching the website, but to no avail.
7 for the radiation…
Ember
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What standard was used by NASA to certify the Dragon capsule controls as safe for crewed flight?
After watching the livestreams of Crew-1 and Crew-2 missions, I was curious about the certification the capsule had to go through, especially with the new control panels which seem to be largely touchscreens.
Of course, by now touchscreens are a…
Mu3
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What paper size do they use on the International Space Station?
We know they have at least one printer on the ISS – that's NASA-supplied so it would be in the US Orbital Segment. Presumably there is a printer in the Russian Orbital Segment as well. (Mir had a teletype.)
My question is – what paper size do they…
Simon Kissane
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Astronauts make a lot of CH₄ and some H₂ as well; do space capsules and space stations have systems to remove these?
While not as much as ruminants, humans emit methane, CH4, natural gas, etc. regularly. While it is less known, we can also emit hydrogen as H2.
What are the sources of molecular hydrogen in human breath?
Recently the Soyuz spacecraft gets to the…
uhoh
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What is "mission design"? What do mission designers do (if such a designation exists)?
The question in meta Is the mission-design tag description wrong? Should the trajectory-design tag be somehow nixed? needs some attention, so I thought I'd turn to our "panel of experts" here in Space SE to get to the bottom of what the term…
uhoh
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How does steel deteriorate in translunar space?
To confirm the identity of a 1966 Centaur booster returning near earth in 2020, NASA took some spectroscopy observations. They didn't match those of the same metal (301 stainless steel) on earth, apparently due to the booster's 54 years in "harsh"…
Camille Goudeseune
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Can a moon orbit its planet faster than its planet rotates?
Can a moon orbit its planet faster than its planet rotates?
Can a moon orbit its planet more than once per the planet's day? It seems possible but I'm not sure.
Are there any known examples of this situation?
user38319
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Could you fly on the Moon, in Earth's atmospheric pressure, by flapping wearable wings?
According to this site, NASA produced a public domain painting representing what the Olympics could look like on a lunar colony. In the upper right of the picture, there are people flying by flapping wearable wings. Given Moon's gravity with Earth's…
TK-421
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