The Philae lander delivered a new data package from Comet 67P/C-G suggesting such icy rocks are made up of several organic materials.
According to BBC News, one Rosetta mission scientist described the blend as "a frozen primordial soup." The discovery is an important one for past studies that previously suggested comets were once the delivery vehicles for many organic materials vital for life.
The new study detailing the findings is published in the journal Science.
"I see this cometary material that we're analyzing as frozen primordial soup. It's the kind of stuff that if you had it, and warmed it up somehow, and put it in the right environment, with the right conditions, you may eventually get life forming out of it," Ian Wright, of the Open University, told BBC News. "What we may be looking at here is our abiological ancestral material - this is stuff that went into the mix to produce life.
"In many ways it's quite a humbling thing to be working on, because this is life before life happened."
The discovery is also encouraging given how the historic comet landing began. The European Space Agency (ESA) could not communicate with Philae for several months because it bounced and landed under a cliff that blocked the sun.
"Imagine you want to build a house and you go to a forest, where there are trees, mud and rocks. You could make a house out of that, but it would be hard work," Mark McCaughrean, the ESA's senior science advisor, told BBC News. "Well, we've now discovered the comet is more like a hardware shop - lots of pre-made building blocks, like door frames, bricks etc. It gives you a head start.
"One of the big questions, though, is this material made on the comet? Or is it made first in space and then incorporated into the comet? We don't know the answer to that yet."
