The European Space Agency’s Rosetta probe, after reaching at the rubber duck-shaped comet 67P last year, is now making efforts to learn more and more about how the icy body was actually formed.

Researchers associated with the mission recently after studying the data sent by the orbiter said the nucleus of comet 67P/ Churyumov-Gerasimenko is made of two formerly distinct bodies that likely came together in a gentle collision in the early stages of the solar system. The findings were published in Nature.

The European Space Agency's Rosetta orbiter began sending back the earliest images of comet 67P's strange, bi-lobed shape in July 2014. Since then scientists have been wondering about the origins of its unusual morphology.

The comet has three distinct regions: a major lobe (the main body of the duck), a minor lobe (the head) and a thin, neck-like region that connects the two.

Matt Taylor of the European Space Agency, project scientist for the Rosetta mission, said, “Since we resolved the comet, the question of whether it was two objects that joined together or one comet that has been eaten away has been dangling. Now we have answered it -- it's a contact binary”.

To reach a final conclusion, an international research team analyzed images of the comet collected by cameras aboard the Rosetta orbiter.

The scientists majorly studied the distinct layers of material called strata that were visible along the comet's many steep cliffs, and which continue at least 2,000 feet into the center of its nucleus. The concentric strata suggest that the structure of the comet is similar to that of an onion, said scientists.

"All together, these three lines of evidence leave a very narrow space for doubt," said Matteo Massironi of the University of Padua in Italy, who led the investigation.

"If you put it together, it looks like you have two onions sitting next to each other, not a single onion with a piece taken out," said Masiero, who wasn't involved in the study.