Hacker News Reader

Comment by olex | Hacker News Reader

Do you have a source for that number? The whole rocket weighs 550 metric tons fully fueled on the pad, I am having a hard time coming up with a way for that to create 50x as much greenhouse gas.

According to Everyday Astronaut's article (https://everydayastronaut.com/rocket-pollution/), a Falcon 9 emits a total of about 600 tons of various gases during a launch. The difference vs the rocket's actual mass seems to be accounted for by water vapor, which comes from ground support equipment and not the rocket itself.

View on HN

> The whole rocket weighs 550 metric tons fully fueled on the pad, I am having a hard time coming up with a way for that to create 50x as much greenhouse gas.

It is in fact impossible. The rocket carries all of its fuel and oxidizer, so basic conservation of mass implies that the total amount of CO2 cannot exceed said 550 metric tons.

Except you might be calculating the material, personnel, property costs also. The launch itself doesn't release that much, but everything leading up to the launch might.

I still disagree with the general sentiment though. Space is more important than most other pursuits.

I don't disagree that space science is important. Space tourism on the other hand is a different thing in my opinion.

> Space tourism on the other hand is a different thing in my opinion.

Space tourism is funding part of the R&D required through for new space to be able to do exploration.

> Except you might be calculating the material, personnel, property costs also. The launch itself doesn't release that much, but everything leading up to the launch might.

Yup, and the supply chain for all of those. At scale, that should go down to a small fraction above the direct emissions (certainly not an order of magnitude more). And if this never becomes at-scale, then we don't have a problem anyway.

The total emissions a launch is responsible for is not limited to the weight of the fully fuelled rocket.

You've also got to include the emissions needed to extract/purify/cool/pump all that fuel/oxidiser (and any other consumables like nitrogen), a percentage of the construction emissions cost for the 1st stage, pre-flight refurb emissions, the whole of the 2nd stage, and some percentage of the Dragon capsule (including alterations made to it). Then you add all of the emissions of the ground operations needed for this flight including 1st stage recovery (and also any flight/boat diversions required from 3rd parties because of the exclusion zone).

I'm also assuming that the altitude you emit certain things at (e.g. aluminium vapourising in the atmosphere) changes their impact vs at ground level.

Personally, I think this mission is more worthwhile space tourism than Bezos who's pretending a high-altitude rocket flight that doesn't reach orbit is 'going to space'... at least they're testing new spacesuits on this mission.

If we're looking at its emissions with all those downstream requirements involved too, the point of comparison would be all the emissions involved in everything that the average American relies on, which is certainly not just 16 tons.

Yes, that seems worthwhile to do - I was just replying to the notion that the direct emissions of the rocket during launch is the limit of emissions. SpaceX is also highly integrated, so I do think the construction and ground operations cost (for everything SpaceX did that would not have happened had this mission not launched) are worthwhile including.

My feeling is that the scale of rocketry isn't large enough that 28k tons of emissions makes a difference vs, say, the much greater number of private helicopter & jet flights (or single-use plastics, or growing & watering crops in a desert, or any of the crazier things we do as a species)

see: https://www.space.com/spacex-starship-rocket-launches-enviro...

"Starship launch produces 76,000 metric tons of carbon dioxide equivalent (a measure combining different types of greenhouse gases in one unit). That's 2.72 times more emissions than those produced by a single SpaceX Falcon 9 launch"

Note, I did mis-quote when I said 28k tons of greenhouse gas, it is 28k tons of CO2 equivalent.

see:

https://www.space.com/spacex-starship-rocket-launches-enviro...

Note, I did mis-quote when I said 28k tons of greenhouse gas, it is 28k tons of CO2 equivalent.

Reply on news.ycombinator.com