You can hear it on grooveshark (http://listen.grooveshark.com/#/s/+39/lM8rl). It's quite a bit different from what you would expect from Queen, but still contains their amazing vocal harmony. It has more of a skiffle feel than their rock/prog-rock sound, and I love the use of the upright bass to provide a sort-of walking bassline. Alongside the vocal harmony they have included multiple acoustic guitars harmonizing with each other and playing the percussive part of the song. The only real drums heard in the song is a bass drum -- sometimes playing along with the upright bass -- and a tambourine. It turns out to be such a catchy song that I'm left with a grin -- no matter what mood I was in beforehand.
'39 was written by Queen's guitarist Brian May. May was working on a PhD in Astrophysics when Queen become popular in the mid 1970's, and ended up putting off completing his PhD until 2008. His background with astrophysics comes out in this song though. The song references the theory of special relativity, and in a round about way the twin paradox. It tells the story of someone setting sail, in the year '39, on a spaceship to discover a new inhabitable planet. With the spaceship moving near the speed of light, the travelers aboard the ship experience time differently than their relatives back on earth. They finally return in the year '39, likely 100 years later for those on earth. The following lyrics seem to indicate that upon returning to earth, the traveler is only a year older, but many years have passed on earth. Presumably the space traveler's wife has died, but he is able to see his wife's eyes in his grandchildren's (or great grandchildren's) crying eyes:
"But my love this cannot be
For so many years have gone, though I'm older but a year
Your mother's eyes, from your eyes cry to me"
What is your favorite space travel / space song?