Since August 2014, European Space Agencies' Rosetta spacecraft has been surveying an odd double-lobed comet 67P/Churyumov-Gerasimenko with a motive to collect data regarding the surface and the environment of the comet.

For a long time, the spacecraft has failed in reaching the dark and cold regions across the south pole of the comet, but now Rosetta has finally accessed this isolated place and has give the first peek at comet 67P's dark side. Rosetta's Optical, Spectroscopic, and Infrared Remote Imaging System (OSIRIS) captured the image.

On the arrival at the comet, Rosetta discovered that the comets northern hemisphere was experiencing summer which lasted 5.5 years whereas its southern hemisphere was totally under dark, cold winters. For nearly past five years, the southern region has received very little amount of sunlight due to which the only way to observe this region of the comet was MIRO, the Microwave Instrument for the Rosetta Orbiter.

Lead author of the study, Mathieu Choukroun from NASA's Jet Propulsion Laboratory (JPL), Pasadena, California, said, "We observed the 'dark side' of the comet with MIRO on many occasions after Rosetta's arrival at 67P/C-G, and these unique data are telling us something very intriguing about the material just below its surface".

Choukroun and his colleagues analyzed this initial data and said that there could be huge amount of ice present within few tens of centimeters beneath the surface in the region.

Choukroun said they were surprised to found that the thermal and electrical properties around the comet's south pole were very different than what they found elsewhere on the nucleus.

"We hope that, by combining data from all these instruments, we will be able to confirm whether or not the south pole had a different composition and whether or not it is changing seasonally," said Mark Hofstadter, MIRO principal investigator at JPL.

"Surprisingly, the thermal and electrical properties around the comet's south pole are quite different than what is found elsewhere on the nucleus," said Choukroun. "It appears that either the surface material or the material that's a few tens of centimeters below it is extremely transparent, and could consist mostly of water ice or carbon-dioxide ice."