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It's good to keep an eye on the carbon impacts of space tourism, but if you're genuinely concerned about climate change, your efforts would be far better spent on promoting the passenger vehicle EV conversion and nuclear/wind/solar buildouts to replace coal plants. I don't think space tourism will become a significant carbon emissions source for at least a few more decades.

Plus the Starship uses Methalox which is the most efficient carbon based fuel in terms of H2O to CO2 ratio. It puts out twice as much water vapor as it does CO2.

I happen to support electrification and renewables. It cost almost nothing (other than some negative rep) to raise a flag about the environmental costs of space tourism. I'm sure early coal fired plants said the same thing about their emissions as well. That surely one more plant or private jet could not hurt the environment. My view is if we normalize and celebrate space tourism now, then there will be no curtailing it in the future.

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.

> 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...

"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.

> 28,000 tons of greenhouse gas

I did the math and it's around 3 in Taylor Swift Year units. Outrageous!

EDIT: For the people who actually eat this BS (28000 tons of a thing from another thing that has a mass of just 500 tons should raise your eyebrows), the actual number is around 120 tons of CO2 for one launch of one F9 booster.

I did mis-speak there. it is 28k tons of CO2 equivalent, my bad.

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"

78,000 metric tons of carbon dioxide equivalent / 2.72 is 27,941 metric tons of carbon dioxide equivalent.

Draft Environmental Assessment for the SpaceX Starship and Super Heavy Launch Vehicle at Kennedy Space Center (KSC) https://netspublic.grc.nasa.gov/main/20190801_Final_DRAFT_EA...

Table 3-7 shows an estimated 83794 metric tons CO2e for 24 starship+superheavy launches, much lower than the figure in that article ( 1872000 tons CO2e for 24 launches ).

I found a 2022 paper by Andrew Wilson, the cited source for the figure in the space.com article. The estimates for carbon footprint for space tourism in that paper are generally consistent with estimate in the Starship + Super Heavy EA and are also much lower than the per-launch numbers of 78000 tons for starship / 27941 tons for falcon 9.

Loïs Miraux, Andrew Ross Wilson, Guillermo J. Dominguez Calabuig, Environmental sustainability of future proposed space activities, Acta Astronautica, Volume 200, 2022, Pages 329-346, ISSN 0094-5765, https://doi.org/10.1016/j.actaastro.2022.07.034. https://pure.strath.ac.uk/ws/portalfiles/portal/139539863/Mi...

> In terms of orbital space tourism, two missions (one past, one planned) assumed to be typical have been analysed: a flight in Earth orbit based on the Inspiration4 mission (Falcon 9, 4 passengers), and a flight around the Moon based on the dearMoon mission (Starship Super Heavy, 10 passengers). Based on this, although different launch vehicles are used, it can be estimated that the carbon footprint of a passenger in an orbital tourism flight is about 660tCO2eq

4 passengers * 660 tCO2eq = 2640 tCO2eq for a launch, ~10x lower

In other words, he increased the carbon output of the US by .0005%, a pretty small relative increase. I am sure scientific knowledge increased more than that.

That's a reasonable calculation I suppose. The 0.0005% increase is in carbon emissions per year by the U.S. -- that same 0.0005% increase in publications would be about 15.

According to this source [1], you are off by two orders of magnitude. Starship also uses way less than you claimed.

[1] https://www.theguardian.com/science/2021/jul/19/billionaires...

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

> I'm kind of done with billionaire space tourism.

Not to be rude, but you were never "doing" billionaire space tourism.