Here is a bit more detail on this find:

“First, not finding ice was a surprise; now, finding it is a surprise,” one of the team, planetary scientist Murthy Gudipati from NASA’s Jet Propulsion Laboratory, told Deborah Netburn at the Los Angeles Times. “It is exciting because now we are starting to understand the upper dynamic layers of the comet and how they evolved.”

Using the VIRTIS-M instrument onboard the Rosetta spacecraft to investigate the reflections, they’ve identified two different types of water ice on the surface – millimetre-sized pure water-ice grains, and 50-micrometre-sized grains.

And in the video below you can listed to those supposide sounds they picked up.

Check back for more updates as they come in.

thanks to sciencealert.com for the great info