[INTRO MUSIC]
So.
How do you weigh a fart?
[THEME MUSIC]
Dr. Michael Levitt, who has decades
of research experience in flatology,
indicates that the typical daily volume
output is between half a liter and 2 liters
of gas once cooled to room temperature.
If you pretend that the fart obeys the ideal gas
law from high school chemistry class, which it probably
does to a decent approximation, you
could work out the mass of the fart
once you know the average molecular mass
of a fart particle.
To get that, we need to know what gases are in a fart
and what ratio they're found in.
This turns out to vary a lot by person and by diet.
I ballparked some average numbers from a paper
in a medical journal that measured the gas
mix in 10 subjects who had been fed
a normal diet plus a bunch of baked beans each day.
I got a density of around 1 gram per liter.
Now, I'm going to assume that our intrepid astronaut has
recently downed a burrito or two,
and would produce 1 full liter, i.e.
1 gram worth of fart mass over a 24 hour period.
For a per fart analysis, assuming a typical 10
to 20 individual farts over the same period,
you would get somewhere between 0.05
and 0.1 grams of mass per fart.
That number may be off by a factor of two or so,
but I doubt it's off by a factor of 10.
And that's how you weigh a fart.
[THEME MUSIC]