The two images were taken at a distance of about three million miles (five million kilometers) and required a series of exposures of 60 to 300 seconds, taken with the wide-angle and narrow-angle camera. The imaging of 67P/Churyumov-Gerasimenko is part of six weeks of activities dedicated to preparing the spacecraft's science instruments for close-up study of the comet. Rosetta has been traveling through the solar system for 10 years, and will arrive at the comet 67P/Churyumov-Gerasimenko in August of this year.

Rosetta was reactivated Jan. 20 after a record 957 days in hibernation. The three U.S. instruments aboard Rosetta are the Microwave Instrument for the Rosetta Orbiter, Alice (an ultraviolet imaging spectrograph) and the Ion and Electron Sensor.

ESA member states and NASA contributed to the Rosetta mission. Airbus Defense and Space built the Rosetta spacecraft. JPL manages the US contribution of the Rosetta mission for NASA's Science Mission Directorate in Washington. JPL also built the Microwave Instrument for the Rosetta Orbiter and hosts its principal investigator, Samuel Gulkis. The Southwest Research Institute in San Antonio developed the Rosetta orbiter's Ion and Electron Sensor (IES) and hosts its principal investigator, James Burch. The Southwest Research Institute in Boulder, Colo., developed the Alice instrument and hosts its principal investigator, Alan Stern.