Scientists from the Max Planck Institute for Solar System Research and the Wendelstein Observatory of the Ludwig-Maximilians-University reported Wednesday the discovery of the new features in images of Comet ISON taken at the end of last week.
The images taken Nov. 14-15 show two striking features within the comet's atmosphere that protrude from the nucleus in a wing-like fashion, they said.
"Features like these typically occur after individual fragments break off the nucleus," Hermann Bohnhardt from the Max Planck Institute said.
Where the emissions from the comet and its fragments meet, the scientists said, a kind of boundary layer is formed that often takes a wing-like form as seen from Earth.
How the comet will develop in the next weeks is still unclear, they said; on Nov. 28 it will fly by the sun at a distance of only 1.1 million miles.
"However, according to past experience, comets that have once lost a fragment tend to do this again," Bohnhardt said.