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1500 questions
23
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3 answers
Are there any (Lagrange) points in the Solar System in perpetual shade?
This answer mentioned thermal cycling made me think of this question: Are there any points in the solar system, such as Lagrange points, where a spacecraft could reside in perpetual shade, protected from heat and perhaps even from the worst of…
gerrit
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23
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8 answers
What factors limit the lifetime of an unmanned spacecraft?
Other than fuel, what factors limit the lifetime of a spacecraft? For example, if someone wanted to send a spacecraft on a 100 year trip round the solar system and back to Earth, could it be done using today's technology, ignoring the orbital…
weasdown
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23
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1 answer
ELI5: Why do they say that Israel would have been the fourth country to land a spacecraft on the Moon and why do they call it low cost?
In the news they say that
Israel hoped to become the fourth country to land a spacecraft on the Moon. Only government space agencies from the former Soviet Union, the US and China have made successful Moon landings.
E.g. Haaretz, BBC
Why don't…
Vladislav Gladkikh
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2 answers
Why not increase contact surface when reentering the atmosphere?
If a craft were to increase the surface area where contact is made with air during reentry, I imagine the heat quantity per area unit would decrease, making the use of (heavy) heat shields less of a problem. It would probably come at the expense of…
Magix
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4 answers
Was the Soviet N1 really capable of sending 9.6 GB/s of telemetry?
On the Wikipedia page for Soviet N1, it says of the control system:
The telemetry system relayed data back at an estimated rate of 9.6
gigabytes per second on 320,000 channels on 14 frequencies. Commands
could be sent to an ascending N1 at the…
nexus_2006
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23
votes
2 answers
Is the cupola, on the inside of the ISS, cold or warm to the touch?
Does the temperature of the surface of the cupola vary when the ISS is in Earth's shadow, compared to when it is on day side of the Earth? Is it cold to the touch when the ISS in the shadow?
Bob516
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23
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1 answer
What celestial body did NASA carve and why is it eating a spacecraft?
The Mashable.com article No one carves a Halloween pumpkin like NASA engineers shows several interesting examples.
But this one I can't figure out. The caption reads only.
Om nom nom.
Question: Can someone identify this celestial object and the…
uhoh
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23
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2 answers
Why was orbital rendezvous considered so controversial?
It's popularly understood that the Apollo program only selected lunar-orbital rendezvous as a mission profile after first thoroughly rejecting the direct ascent profile. It seems as though the decision to go with LOR was highly controversial at the…
kgutwin
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Why does the Falcon 9 use RP-1/LOx and not LH2/LOx?
Why does SpaceX use RP-1 in the first and second stages of their rockets?
In my view at least the second stage could use hydrogen as it currently is not being reused.
I am aware that you have higher initial technical requirements than with RP-1 but…
CKA
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23
votes
8 answers
Is there any economical way to move the water from the Martian poles to the people?
update: Water at the poles has some more recent news:
Science: 03-August-2018 Radar evidence of subglacial liquid water on Mars
EarthSky.org: 28-Sept-2018 Pink lagoon provides clues to possible Mars life
Space.com: 25-July-2018 Mars' South Pole…
uhoh
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3 answers
Where did the famous "end of decade" deadline come from?
In his address to Congress on 25th of May 1961, John F Kennedy committed for the first time to land a man on the Moon and bring him safely back before the end of the decade.
But the feasibility studies for the original Apollo program had ended less…
Diego Sánchez
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23
votes
5 answers
What is the general shape and size of a space probe, and how are they launched?
I am totally blind, and I haven't felt any models of space probes, so I have no idea how big they are, what their general shapes are, or what kind of launch systems they use.
I'm assuming space probes are not as big as space capsules, so they…
HeavenlyHarmony
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23
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1 answer
Why does the ISS cupola have Interior Protective Sliding Windows
As shown in the center right part of the picture, the International Space Station cupola has an interior sliding window frame, maybe detachable, such as cameras among other instrumentation.
Note that this device is mounted in only one window…
Brethlosze
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23
votes
3 answers
Could a spy satellite in orbit be recommissioned to do astronomy?
Since the National Reconnaissance Office offered NASA a left-over Hubble sized mirror that might be used for the WFIRST space telescope, I wonder if the NRO has satellites in operation that could do similar astronomy? Would the instruments that are…
LocalFluff
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4 answers
Starman/Roadster in a=1.795 AU orbit, now what's the method to this madness?
The question SpaceX's 4,425 satellite constellation - what's the method to the madness? received an excellent answer explaining the rationality behind the madness plan.
Elon Musk's tweet (spotted here) shows the figure below, indicating a semi-major…
uhoh
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