HN Explorer

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TazeTSchnitzel
What are the greenhouse gas emissions of a typical satellite launch like?
philips
"Googling around, I find that the Falcon 9 uses about 25,000 gallons of kerosene in the first stage and 4,600 gallons in the second. The second stage burn is largely above the atmosphere so its contribution to greenhouse warming is negligible, but I'll include it anyway. Since the Falcon Heavy has three first stage cores, its total kerosene capacity would be in the neighborhood of 80,000 gallons."

"Each Falcon Heavy launch then will contribute about 0.017 % additional greenhouse gases to the atmosphere beyond what is already being generated by automobiles in the U.S. on the day of the launch."

via https://www.quora.com/How-much-greenhouse-gas-will-be-emitte...

pixl97
I'm guessing you could make bio-kerosene if you wanted to, though a lot of carbon goes into that too.
paulsutter
The carbon going into bio-kerosene is a good thing (so when it goes back out it balances to zero)
DuskStar
I think the point is that while the plant itself might balance out, the whole process does not due to all the other inputs (fertilizer production, farm machinery, transport, refinement etc) that are required.
bradyd
Space X is planning on using methane instead of kerosene in their next generation rockets. The want to be able to use co2 and water to produce the methane and liquid oxygen fuels.
StavrosK
> The second stage burn is largely above the atmosphere so its contribution to greenhouse warming is negligible

Won't it just fall back to earth?

[dead] xbdobd
Interesting question, I don’t know the answer, but why would a gas fall back down to Earth?

Wouldn't it expand to fill in the volume?

On the other hand the jet is angled downward (or opposite the direction of increasing orbital energy) so I guess it does fall down.

But when it hits the upper atmosphere, wouldn’t it break apart into its constituents by the UV?

I dunno!

esotericn
471 million gallons of fuel per day is insane.

There's about 300M in the US, right? 1.5 gal per person.

~70 miles for every man, woman, and child.

I knew you guys were car-dependent, but that's on another level.

nine_k
Does this number include trucks?

Trucks move a lot, even though freight railways are well-developed in the US.

[dead] xbdobd
70mi for a realized national fleet average of 35 mpg? No way. More like 40 mi for a fleet average of 25. (Are you using imperial gallons?)

On my commute I average 17 mpg on a 28 mi round trip. 21 if I’m really soft on the throttle.

Hills and city driving kill mpg.