Roclket air polution

[Kevin_Hall]

Does anybody know if and how rockets polute the air?

[studiot]

8 minutes ago, Kevin_Hall said:

Does anybody know if and how rockets polute the air?

Partly depends on the chemistry of the fuel. Hydrazine is particularly bad as it produces oxides of nitrogen.

Here is a NASA video  - warning it's over 20 minutes long.

 

Edited December 7, 2021 by studiot

[John Cuthber]

2 hours ago, studiot said:

Hydrazine is particularly bad as it produces oxides of nitrogen.

Not very relevant if you are using N₂O₄ as the oxidant. 😉

[skydelph]

Yes, the rockets do pollute.
There is not one consolidated answer to that question in numbers due to the facts that there is no exact data of all the World'd launches and tests performed. As well as there is no exact dedicated measurements in the atmosphere.
But there are some useful articles on that:

https://www.space.com/rocket-launches-environmental-impact

https://everydayastronaut.com/rocket-pollution/

[studiot]

15 hours ago, John Cuthber said:

Not very relevant if you are using N₂O₄ as the oxidant. 😉

Thanks good point.

[swansont]

!

Moderator Note

How about we discuss the topic of the thread and not extraneous detail of what's in someone's profile

 

[skydelph]

I haven't seen a clear statistics on the propellants used in sense of launches and hence the actual pollution from the rockets that we have today.

There are a lot of factors, the most famous launches, tests and results are in the pioneering companies' reports all over the web.

Solid rocket fuels can have a severe carbon footprint. But most of the rockets use either liquid or hybrid propellant engines: using solid at one stage and switching to the liquid on another. In some implementations solid propellant produces the best thrust in low thick the thickest atmosphere layers, at higher positions - liquid propellant is used.

Liquid hydrogen fuel produces water exhaust. But it should be taken into account at the same time that hydrogen production causes significant carbon emission. Ozone depletion is also one of the rocket's exhaust impacts.

‘Solid fuel rockets have lower specific impulse, a measure of propellant efficiency, than liquid fuel rockets. As a result, the overall performance of solid upper stages is less than liquid stages even though the solid mass ratios are usually in the .91 to .93 range, as good as or better than most liquid propellant upper stages.’ - Wikipedia https://en.wikipedia.org/wiki/Rocket_propellant.

A rocket's purpose (hence, the engineering design of mechanics and dynamics) dictate the factors of using a specific engine and propellants: travel distance, reusability, multi-start, net load, fuel. The typical limitation is combustion stability.

Though the rocket launches are not so frequent to have a significant impact in the overall pie chart of the World’s carbon footprint, the space industry took it’s advantage on eco-fuel implementation.

The rocket propellant new engines are being designed and tested non-stop.

Example:

‘The Apollo Constellation Engine (ACE) is a Hall effect thruster propulsion system: Multi-propellant capability with Krypton, Xenon, and proprietary propellants.’ - September this year.

Hybrid rocket: https://www.skyrora.com/skyhy

This is a list of long read for a deep dive into the chemical part of the propellants:

https://www.sciencedirect.com/topics/earth-and-planetary-sciences/rocket-propellant

 

Edited December 14, 2021 by skydelph