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Operating system of New Horizons spacecraft
I've been doing some searching and I can find some technical details about the flight computer of the New Horizons spacecraft. What I've found is:
It has a Mongoose-V 32-bit CPU (a radiation hardened MIPS R3000) running at 12MHz.
I'd like to find…
T.K.
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Does the ISS have zenith-facing windows?
I was looking at the NASA image of the day today, and it made me wonder about the windows on the ISS. I often see pictures of Earth taken from the ISS, but I was wondering if they had any windows that looked "up", towards zenith, opposite to Cupola…
duzzy
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Why choose to crash the Apollo lunar lander ascent stage after it ascended?
What influenced the end-of-life planning for the Apollo lunar lander ascent stage after it ascended and the crew returned to the command module?
I was looking at Wikipedia for Apollo Lunar Module. It says,
Having completed its job, the LM was…
tahsmith
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Criticality in space junk
What density of satellites in LEO is permissible before a single collision has a reasonable chance of triggering the catastrophic destruction of everything in orbit? How many orders of magnitude are we below this level presently--is this a…
Rex Kerr
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Any possible setbacks in deorbiting larger space junk and let it burn up upon reentry into atmosphere?
Space junk, orbital debris, or space waste pose a risk on functional satellites and space laboratories / stations in orbit around Earth. According to Wikipedia:
Currently about 19,000 pieces of debris larger than 5 cm are tracked,
with another…
TildalWave
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Why is Falcon 9's shape so tall and skinny?
Compared to most rockets I know of, Space X's Falcon 9 seems unusually tall and skinny. The v1.1 version is nearly 70m tall, yet only 3.6m thick.
For comparison, Atlas V is 58m tall and 3.8m thick, Proton-M is 58m tall and 7.4m thick, etc…
So,…
radex
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Why is it that during reentry phase a capsule cannot communicate with mission control?
During reentry phase into the Earth's atmosphere the heat produced by air friction does not allow any communication with the surface. Why does the heat interfere with electronic frequencies and signals?
user55
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Why does Dragon 2 abort with the trunk attached?
In the Dragon v2 abort test yesterday, it lifted off with its unpressurized trunk in tow, then ejected the trunk at apogee. Is this the real abort profile? Wouldn't it be easier to pull away without the trunk?
If it's the real profile, why spend the…
Potatoswatter
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How stable would a Falcon 9 first stage be after it has landed on a drone ship?
Presumably, the booster would be a very light, very tall tube (Most of the fuel spent) standing on 4 fairly small legs on a ship in the middle of the ocean. It would also still contain some LOX and RP1 that would start boiling fairly soon after…
neelsg
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Could a spacecraft be made out of lunar materials?
Would it be possible to construct a working spacecraft using only materials extracted from the lunar surface? If not, what materials would we have to be ferried from Earth for this purpose?
Gwen
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Why were Delta II SRBs asymmetrically mounted?
This diagram of the Delta II 74xx-series shows 4 booster rockets mounted rather asymmetrically. All other things being equal, it looks like the net thrust of the set would push the rocket off-axis.
Why are the boosters not mounted in a radially…
Russell Borogove
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Why can the Falcon 9 be reused while the SLS cannot?
In reading about SLS, I learned that the reason they won't reuse their rocket is that the weight of the parachutes to enable recovery is too much of a sacrifice. How is the weight of the hardware and fuel NOT too much of a sacrifice for Falcon 9?
Asalt
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Do the Voyager space probes perform time synchronization regularly?
According to JPL: http://voyager.jpl.nasa.gov/mission/weekly-reports/
Voyager 1 travels at a velocity relative to the Sun of 19.03 km/s (or 0.000063478 c, or a time difference of ~ 0.0005 seconds per year), and Voyager 2 travels at 15.428…
Shuhao Cao
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Why does SpaceX appear to get less funding from NASA for the same thing as competitors?
Been looking at the amazing success of SpaceX and from what I found, the contracts they get awarded don't seem to make much sense. It looks like they are simply getting paid less each time NASA awards a contract. Examples that I found:
Commercial…
neelsg
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Would the lunar analogue of geothermal energy be practical on a lunar base?
Given sufficient liquid in the form of water or other suitable medium, would the use of the lunar analogue of geothermal energy be practical or feasible for powering a lunar colony?
Wikipedia (referenced) gives an internal temperature for the Moon's…
James Jenkins
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