A large and growing crack on the comet 67P/Churyumov-Gerasimenko recorded by European Space Agency's Rosetta mission suggests that the comet might split up one day, says a new study.
A 1,600-foot-long fracture that runs through the comet's neck was spotted in August 2014. The fracture was found to have increased in width by about 100 feet by December 2014.
In images taken in June 2016 by the Rosetta probe, a new 500- to 1,000-foot-long fracture was identified parallel to the original fracture spotted in August 2014.
"The large crack was in the neck of the comet, a small central part that connects the two lobes," said the study's leader Ramy El-Maarry from the University of Colorado at Boulder in the US.
"The crack was extending, indicating that the comet may split up one day," El-Maarry said.
The study published in the journal Science summarises the types of surface changes observed during the two years that the European Space Agency's Rosetta spacecraft spent investigating the comet.
Notable differences are seen before and after the comet's most active period — perihelion — when it reached its closest point to the Sun along its orbit.
"As comets approach the sun, they go into overdrive and exhibit spectacular changes on their surface," El-Maarry said.
Between August 2014 and September 2016, Rosetta orbited comet 67P during the comet's swing through the inner solar system.
"We saw a massive cliff collapse and a large crack in the neck of the comet get bigger and bigger," El-Maarry said.
"And we discovered that boulders the size of a large truck could be moved across the comet's surface — a distance as long as one-and-a-half football fields," he pointed out.
Rosetta is a European Space Agency mission with contributions from its member states and NASA.