Questions tagged [chemistry]
Questions regarding the application of chemistry in space exploration, for example the composition of rocket propellants.
5
votes
1answer
147 views
Density of propylene when used as rocket fuel, and advantages (if any) over RP-1?
Recently Vector space from USA has said that propylene is a better choice of fuel than RP-1. See Ars Technica's After a decade of testing, propylene rocket fuel may be ready for prime time
Why is ...
0
votes
0answers
30 views
Is abundance of chemical elements in the asteroid belt / solar system real through higher concentrations?
Given humanity would be once able to access any minerals in the asteroid belt and moons of planets, would be there some chemical elements (if stable isotopes exist) still considered as rare?
20
votes
1answer
254 views
Rock flipping operation
After the recent announcement of complex organics being found on Mars within the curiosity rover's meager 5cm drill depth, I had an idea about artificially increasing it:
Is curiosity rover's arm ...
5
votes
2answers
440 views
What are the energy-to-mass ratios of some fuels/oxidizers, when including the oxidizer?
Energy-to-weight ratio is an important parameter. We would like it to be high so we don't have to carry around much fuel.
Maybe you've heard some of the numbers for common fuels. Hydrogen is about ...
1
vote
0answers
74 views
Speculation. Will this “turning-co2-into-O2” zeppelin work in Venus? [closed]
Background: Me and a friend are trying to "colonize" Mars and Venus. He has Mars, and I have to "colonize" Venus. So, my intention was to do a slow terraform by creating zeppelins that convert CO2 ...
4
votes
2answers
92 views
What is the process to produce a chemical composition spectrum of a celestial body?
I have come across this spectrum, which depicts the chemical composition of Titan's atmosphere:
Taken from here.
I would like to know how do scientists generate such spectra, starting with capturing ...
4
votes
1answer
127 views
Got Milk? Why is the term “colloid” used in “Colloid or Electrospray thruster”?
From this answer to the question "Difference between colloid thrusters and electro spray thrusters" I've extracted the following:
According to the Wikipedia article Colloid thruster they are the same ...
3
votes
2answers
82 views
What is a pickup ion?
I've been reading several publications about Titan's atmosphere and chemistry, and the term "pickup ion" kept appearing here and there (see this publication for example).
I looked it up and found the ...
3
votes
1answer
63 views
How (if possible) can we assess the isotope variations on martian soils?
I'm personally interested in the biological implications of different isotope variations on biology. This can be tested on earth by separating them and just observing, but determining the isotope ...
5
votes
1answer
3k views
Can I make my own RP1? [closed]
Is it possible for me to buy kerosene from a local store and then try to refine it to the extent where it would be considered RP1. If so how would I do it? For those who are wondering me and a group ...
6
votes
1answer
71 views
Meteor color hints at chemistry
This recent meteor over the midwest. Reports described it at blue / green. I have seen blue / white, red and yellow meteors. I presume red means iron, green means copper. Can meteoritics or meteor ...
3
votes
1answer
74 views
What is $C_p$ in the fuel efficiency equation?
On page 94 of Ignition! an equation for "Frozen equilibrium calculation":
$$
c = \left[ 2H/M \right]^{1/2} \left[ 1- \left( {P_e \over P_c} \right) ^{R/C_p} \right]^{1/2}
$$
All quantities are ...
1
vote
2answers
199 views
Chemical Fuel Improvements
With advances in chemical engineering, could chemical propulsion have a fuel (or fuels) that would allow it to compete with newer, more advanced form of propulsion (such as electrical or nuclear) or ...
3
votes
1answer
260 views
What proportion of a rockets fuel remains unburnt?
Presumably liquid rocket combustion is never 100% efficient, so what proportion of fuel does typically remain unburnt, venting into the atmosphere, and does this vary for different rocket designs and ...
30
votes
7answers
6k views
Do things get dirty in space?
I'm writing a computer game involving space exploration, where the player will come across space ships/stations that are hundreds/thousands/tens of thousands of years old. I'm also trying to make it ...
7
votes
3answers
2k views
Is there a maximum Isp for “exothermic chemical reaction rockets”?
The question Is there a maximum $\text{I}_{sp}$? reminded me that I once read somewhere that the maximum possible $\text{I}_{sp}$ for a rocket engine based on expansion driven by exothermic, ...
9
votes
5answers
795 views
What limits burning speed of solid propellant?
SRBs and missiles use grain to regulate thrust over time, as only exposed surface of the propellant burns.
But what causes propellant to burn only on the surface, and regulates the speed at which the ...
10
votes
1answer
1k views
What is the cause of the blue light from LH2/LOX rocket engines?
Below are some screen shots from circa June 2016 launch (or re-launch) videos by Blue Origin (video link) and SpaceX (video link). The New Shepard burns $\text{H}_2$/$\text{O}_2$, while the Falcon 9 ...
5
votes
1answer
1k views
What causes the green flash during Falcon 9's ignition?
Right before Falcon 9's engines start, there's a green flash. I assume it's some kind of chemical ignition.
What makes the flash the color green?
3
votes
1answer
147 views
How could you create water and air from materials in the Solar System?
If you don't have access to Earth(but still the moon) or the Sun, where could you obtain enough hydrogen, oxygen, and nitrogen to create enough water and an N2 and O2 atmosphere for, say a population ...
5
votes
1answer
97 views
Should we expect the surface rocks of Venus to be oxide poor.?
My thinking is that in an atmosphere rich in hot sulfuric acid they couldn't stand a chance. Although I am unsure of what exactly would be going on chemically at the interface between the venerean ...
5
votes
3answers
396 views
What would adding 15% nitrogen do to pure oxygen as an oxidizer?
I'm working through Sutton's "Rocket Propulsion Elements," (8th Ed.) and it is mostly gibberish. However, I understand a little bit. Anyways, the question is: When using RP-1 as a fuel, your oxidizer ...
3
votes
1answer
235 views
Mars: Readily usable sulfur for sulfur concrete?
Sulfur concrete is a mix of sulfur and aggregates that make a strong, quick-hardening concrete that is likely to be used for construction on Mars, which has a great deal of sulfur. Most experiments, ...
8
votes
1answer
1k views
Is there salt in space?
Is it possible for ordinary table salt (sodium chloride) to form on a lifeless planet / moon / comet / other body? Is liquid water required? Would it be common or nearly-impossibly rare? Part of a ...
3
votes
3answers
371 views
Would it be more viable to process moon rocks into Helium-3 on the Moon than doing so on Earth?
Helium-3 is a substance that is very useful for nuclear fusion, which can generate a lot of power. Unfortunately we don't have a lot of it on Earth, but on the Moon it can be processed from basic moon ...
3
votes
1answer
183 views
Could there be a phosphorous cycle on Venus?
Most of what I read says there is not any Phosphorous on Venus which I take to mean none in the atmosphere or none detected. I mean it get hit by Iron-nickel meteorites and probably has some apatite ...
5
votes
3answers
159 views
Why do we search for extra-terrestrial water?
When searching for signs of extra-terrestrial life, the key primary challenge as of now seems to be searching for signs of water on other planets. Presumably, this is because on Earth, water is ...
6
votes
1answer
104 views
How much energy does it take to extract water from silicate?
Browsing Asterank, it seems that people believe many asteroids have large amounts of iron or magnesium silicate. These compounds may come in a hydrated form which contains water, but it is chemically ...
9
votes
2answers
312 views
What mitigation procedures are in place in space systems to prevent whisker growth?
It has been found (from missions like the Long Duration Exposure Facility, LDEF) that some metals, especially tin and cadmium in solders, used in space-electronics assemblies, form crystal whiskers ...
8
votes
2answers
81 views
Monoatomic species at orbital altitudes
Besides monoatomic oxygen, what other monoatomic or chemically reactive atmospheric or environmental constituents, if any, are present at orbital altitudes that aren't present at lower altitudes, and ...
10
votes
2answers
1k views
What is required to produce rocket quality methane fuel and oxygen from Mars' atmosphere?
Turning $\require{mhchem}\ce{CO2}$ and some hydrogen into $\ce{O2}$ and $\ce{CH4}$ seems pretty straightforward and has been known since early chemistry in the 19th century. But what about the quality,...
17
votes
1answer
740 views
What does burnt Aerozine-50/N2O4 smell like?
The lunar astronauts universally described the smell of moon dust as similar to spent gunpowder.
The exhaust gases from the LM's descent propulsion system (which combusts Aerozine-50 with N2O4) didn'...
9
votes
0answers
648 views
Terraforming Venus with the Bosch reaction, using hydrogen from Jupiter [closed]
OK, so chemistry and physics are not my strong suit, so this idea is just cobbled together from stuff I've heard can be done. But I'd be curious if it is at all plausible, and what the most likely ...
5
votes
2answers
2k views
What does “self-pressurizing” mean in regards to propellant tanks?
I've come across this term a few times. IIRC, liquid hydrogen is "self-pressurizing", but other fuels are not. Apparently, if a propellant is self-pressurizing, we do not need to build any complex ...
7
votes
1answer
917 views
Could aluminum undergo a thermite reaction with Martian dust?
From what I understand, Martian dust is primarily composed of iron oxide, which is one ingredient for a thermite reaction. If heated to the proper temperature, would aluminum (possibly powdered) react ...
2
votes
1answer
235 views
Valuable materials in Saturn rings and comets vs. Carbonaceous chondrites
Most common type of asteroids in inner solar system are carbonaceous chondrites while most common type of object in outer solar system are comets. Carbonaceous chondrites are very rich on carbon and ...
9
votes
2answers
921 views
What is meant by 'Organics' when discussing space exploration?
A recent news article Comet landing: Organic molecules detected by Philae (BBC 18 November 2014) talks about 'Organic molecules' being found on a comet. The question here Any regolith lunar samples ...
3
votes
1answer
2k views
What are the odds of finding a lifeless planet with breathable air?
As I understand it, our current breathable atmosphere on Earth is the result of early lifeforms transforming huge amounts of CO2 into O2. Before early life, even Earth's atmosphere wasn't livable for ...
7
votes
1answer
89 views
Electrolysis Production Rate
Given the interest in using lunar water for propellant manufacture, how do you calculate the production rate for electrolytic breakdown and liquefaction of water into cryogens? A corollary question ...
