Rosetta is "the sexiest space mission there's ever been," according to one of the European Space Agency's scientists.
"The science is shaping up wonderfully," Rosetta project scientist Matt Taylor said.
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The tourists had no idea they were about to be dropped off at the star-studded ceremony to meet A-listers.
It comes just weeks after actor Michael Keaton confused the names of films Hidden Figures and Fences at the Golden Globes.
All eyes were on the stars as they arrived on the red carpet for the 89th Oscars. But who won in the fashion stakes?