As Rosetta began homing in on Comet 67P/Churyumov–Gerasimenko in the weeks leading up to its arrival in August 2014, it became very clear that this was no ordinary comet. But its striking shape was only just the beginning of the comet’s surprises. After more than two years spent living with the comet, Rosetta scientists reflect on some of the mission’s unexpected discoveries, the mysteries solved and the new questions raised.
Compilation of the brightest outbursts seen at Comet 67P/Churyumov–Gerasimenko by Rosetta’s OSIRIS narrow-angle camera and Navigation Camera between July and September 2015. Credits: OSIRIS: ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA; NavCam: ESA/Rosetta/NavCam – CC BY-SA IGO 3.0
“Rosetta has completely changed our picture of comets,” says Eberhard Grün, an interdisciplinary scientist working on the Rosetta mission at the Max Planck Institute for Nuclear Physics in Heidelberg, Germany.
“Previously, they were pictured as dirty ice balls – or, as some prefer, icy dust balls – but now we know them, or at least this one, to be geologically complex worlds where a myriad of processes are at work creating the incredible surface structure and activity of the comet.”
While many of the results from the mission highlight the findings of individual instruments ...