http://www.lyricsdepot.com/monty-python/galaxy-song.html
It’s a great song. I just wonder if all the numbers and such are correct.
<unresearched>
Yep, those values are all approximately right.
However, at the end it claims that the universe cannot expand faster than the speed of light. This isn’t true, the expansion is not constrained in this way.
</unresearched>
IIRC the Universe does expand at light speed. The only exception to this was during the Inflationary period very, very shortly post Big Bang and only lasted fractions of a second.
The song is largely correct as noted.
Doing a couple of quick number crunches:
Based on a orbital radius of 98 million miles, I get the earth orbiting at 19.5 miles/second, which is pretty close to the song’s claim. Using wikipedia’s figure of a rotational velocity of 465.11m/s (equatorial), I get 1039.8miles/hr, which is a bit more than the song’s claim of 900. I think my math is right.
I’m too lazy to go through the rest of the song.
I believe all of the numbers in it save one were accurate when it was composed. The estimated number of stars in our galaxy has dramatically increased since then. Wikipedia says the estimate is now 200-400 billion stars.
Idle definitely got the speed of light wrong. To 2 significant figures, it’s much closer to 11 million miles a minute rather than the claimed 12, and that was a known fact back then too. I once confused my friends by singing it that way during a Monty Python singalong. 
*** Ponder
<still can’t be bothered to google this>
The visible universe must necessarily increase in size at the speed of light.
The Universe proper though needn’t do so. I can’t remember what the speed is exactly, but it’s not constrained to light speed and there’s even a theory called the Big Rip where the expansion of the Universe eventually accelerates to the point that everything is pulled outside of the light cone of everything else.
Consider that the balance of evidence suggests that the Universe’s expansion is accelerating. How could this be the case, if the Universe’s expansion were limited to light speed, and it were already at that speed?
Technically, the second line stating that the Earth is revolving at 900 mph is wrong. They are referring to the Earth’s rotation.
The time it takes the Sun to revolve once around the galactic center is called a “cosmic year” which the song says is 200 million years. Some actual values of this are as high as 250 million years.
http://hypertextbook.com/facts/2002/StacyLeong.shtml
Yes, I know I am nitpicking, but since this is the SDMB, I think you would expect a rather exacting analysis. (No doubt someone else will come up with other errors). 
Yabut…
“Rotating” doesn’t rhyme with “evolving”.
Of course, the full statement “just remember that you’re standing on a planet that’s evolving and revolving at nine hundred miles an hour” really means that the planet is evolving at nine hundred miles per hour, which doesn’t make sense at all. 
No, it could be taken as two separate statements,
1] (Evolving) and (revolving at 900 mph)
as opposed to
2] (Evolving and revolving) at 900mph.
But as you can see, I’m a math person, not a grammer person.
For my money, option one would be correctly written as “[the planet is] evolving, and revolving…”
Without the comma, it reads to me as option two.
If we didn’t pick nits, we’d just end up with lice.
Let’s just call it creative licensce.
But then I can’t complain.
You can certainly complain about that “creative licensce” pun. That was horrible.
But wouldn’t the speed of rotation be about 900 mph at the latitude of England? If not, well hey, it’s just a song! Poetic license, you know.
Some analysis here: http://www.bbc.co.uk/dna/h2g2/A2163133
I’m surprised to be the first person to point this out, but the statement “the sun that is the source of all our power” is flatly wrong, although it was once true. Nuclear power isn’t derived from solar energy. All other forms of energy are solar, if often very indirectly (petroleum comes from the remains of living creatures, which needed the energy of the Sun to exist; hydroelectric power is only possible because of weather that is created by solar energy, etc. etc.) but radioactive elements like uranium were created before the formation of our solar system, and owe nothing to the Sun for their existence.
Thanks, everybody, and especially for this, Peter Morris.
For your viewing enjoyment: http://youtube.com/watch?v=KuQszlbhEeE
You’re welcome.
Of course, I’ve always felt that the biggest and most obvious error is the way Eric Idle rhymes “two-hundred-million years” with “expanding universe.”
So, the Galaxy Song is substantially accurate (within the constraints of the science at the time).
This begs the question - is the Philosophers Song also substantially accurate?
Si
Well, John Stuart Mill *did *talk about free will…
Beyond that I think it’s going to be hard to verify the true historical accuracy this particular composition.