71
votes
Accepted
Why doesn’t NASA build its rockets using graphene?
The Technology Readiness Level (TRL) of graphene is at 2 or 3 as far as I can tell. And that is TRL as related to making very tiny stuff.
Anything used to build a structure for aircraft or spacecraft ...
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44
votes
Why doesn’t NASA build its rockets using graphene?
Besides the fact BradV pointed out that we don't have the technology to do this yet, the fact is that graphene on a macroscopic scale would not perform as well as the numbers you cited suggest. All ...
- 11.4k
28
votes
Feynman famously criticized the Space Shuttle program for not delivering any value to science. Did things improve in that regard since the 1980s?
Sadly Feynman died in 1988, and therefore did not live to see the Shuttle used to launch the Hubble Space Telescope in 1990, or correct its optics in 1993. Then he surely would have seen scientific ...
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21
votes
Feynman famously criticized the Space Shuttle program for not delivering any value to science. Did things improve in that regard since the 1980s?
Paper by William Bianco and Eric Schmidt Knowing What We Are Getting: Evaluating Scientific Research on the International Space Station starts with the very quote by R. Feynman you quoted as well.
...
15
votes
Have we done any research trying to reach the speed of light?
Not on macroscopic scale. The Special Relativity theory is fairly well understood and says it's impossible for any objects that possess rest mass, period. The closer you get to speed of light the more ...
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13
votes
Accepted
Concerns/challenges with LOX as a regenerative coolant
To answer your first question: one of the main problems with using the oxidizer in general is oxidizing of the cooling channels. Any hot oxidizer has this problem, but oxygen definitively has this ...
- 1,144
12
votes
Titan vs Mars for colonization
The biggest obstacle of living on Titan is bound to be it's insane cold. People say space is cold, but space is a vacuum. A thermos bottle uses a vacuum as insulation. So wearing a space suit in a ...
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10
votes
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Titan vs Mars for colonization
Some advantages of Titan are:
abundant nitrogen,
a thick atmosphere that will protect against radiation (the extra distance from the Sun also helps)
Lower gravity (and atmosphere) makes access to ...
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8
votes
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Starlink's autonomous collision avoidance
I don't think there are any papers about it, but here's what I've gleamed from my studies on it.
As you mentioned, they use information from the DOD, specifically Space-Track, or C-SPOC, or J-SPOC. ...
- 122k
8
votes
Has anyone seriously considered a space-based time capsule?
future
Perhaps a time capsule will feature prominently in one of these: What would be the (most difficult) challenge to make a 10,000 year satellite?
microfilm
Answers to Is there really microfilm on ...
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7
votes
What are the top grand challenges in space exploration today?
To give the desired global perspective, I surveyed grand challenges identified by NASA, Roscosmos, and ESA.
1. Human presence in space
All three identified areas of growth in terms of human missions. ...
- 23.8k
7
votes
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"UK schoolboy corrects Nasa data error" - what precisely was the "error"?
The source of the data is the Radiation Environment Monitor. Lawrence S. Pinsky is listed as co-investigator.
This Radiation Environment Monitor demonstration will provide information that is ...
- 128k
7
votes
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Were any mammals born in space (or are there any confirmed planned missions to breed them)?
Almost certainly if a mammal would have given birth in zero gravity, it would have been mice, rats, or other similar rodents. I have found a few studies which had mice that were pregnant at launch, ...
- 122k
7
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Why doesn’t NASA build its rockets using graphene?
Just because a substance has impressive specific strength, doesn't mean it has all the properties needed to make it generally useful.
Specific strength, the ratio of strength to weight, is a very ...
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6
votes
What publishing authority (and year of publishing) was the first to use the term 'occultation'?
It was not "commissioned" in any sense; the word has been around for that purpose in scientific discourse for a very long time. See, for example:
The Occultation of the Planet Mars by the Moon, ...
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6
votes
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Post-shuttle, "Have any animals that have been studied onboard the ISS come back alive?"
Yes.
A nice example would be the recent splashdown of the first SpaceX Dragon capsule to have been re-used after a previous visit to the ISS.
See for example Spaceflight Now's July 3, 2017 article ...
- 149k
6
votes
Accepted
What is the smallest object our current technology is capable of launching into space?
The atmosphere makes it harder. On a per-kilogram basis, it is much more efficient to accelerate massive objects through the atmosphere than light ones. That's because the mass of the spacecraft is ...
- 11.4k
5
votes
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Getting to Mars requires 12 ISSs of mass w/o tech advances?
I found the source.
https://www.nasa.gov/pdf/553607main_APL_Bobby_5_27_11_DW2.pdf, slides 7 and 9.
In case anyone else ever goes looking for the source of these images, I hope this post helps them.
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5
votes
Mining lunar thorium for building nuclear rockets on the Moon
Mining lunar thorium gains you nothing. Thorium is not fissile and cannot be used to fuel a nuclear rocket, power plant, or RTG.
Designs for "Thorium" nuclear power plants use thorium as a fertile ...
- 1,768
5
votes
How much power would a spacecraft's magnetic shield require?
This might be of interest: CERN, in collaboration with the European Space Radiation Super Conducting Shield project are using advances in super conductor technology to develop a super conducting ...
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5
votes
Accepted
Rabbits in Space
Public information on rabbits in space is surprisingly sparse. The earliest instance I have been able to find is the July 2, 1959 launch of the Soviet R-2, which reportedly carried the first rabbit ...
- 23.8k
4
votes
What animals, if any, have reproduced in space?
The first animal that conceived her offspring in space was a cockroach named Nadezhda. She was one of many cockroaches on board the Russian satellite Foton-M 3 (September 14 - 26, 2007) After they ...
4
votes
Has dependent one-carbon metabolic pathway been successfully linked to ocular health of astronauts?
Yes, the 1C pathway has been successfully linked to ocular health of astronauts, and it seems Scott Smith is still involved in the research.
A study involving 49 space station astronauts established ...
- 23.8k
4
votes
Where can I find data on current space agency contracts?
This website has access to "all current NASA contracts." The organization seems kinda goofy (it seems to be a way for politicians to find out how much NASA is spending in their district) but if you ...
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4
votes
Getting to Titan and beyond - technology knowledge management to get... anywhere
No, there isn't. Each space agency (NASA, ESA, Roscosmos...) has its own databases and repositories, and even within e.g. NASA one hand doesn't always know everything about what the other hand is ...
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4
votes
Has anyone seriously considered a space-based time capsule?
The chances of those threats causing the extinction of humanity, or even "just" the collapse of industrial civilisation, seem unlikely. For example, this Vox article summarises the ...
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4
votes
Has anyone seriously considered a space-based time capsule?
Putting a time capsule in space would be very expensive, the cost will be proportional to weight. So only compact, lightweight and reliable data recording media are possible. Special concern should be ...
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