Our new images from the camera system OSIRIS on ESA’s spacecraft Rosetta shows that Comet 67P/Churyumov-Gerasimenko has a spectacularly shaped nucleus! The nucleus consists of two large pieces with different shape, connected at a small contact surface.
One should not look too closely for details in a movie like this. The reasons is clear once we look at one of the original images below. The camera has a limited resolution and the original image consists of a number of squares, or “pixels”, that each have recorded a certain light intensity. We do not know how the nucleus looks like within each pixel – but we can guess!
During so-called image processing, mathematical algorithms are used in an attempt to re-create how an object really looks like, before it got smeared out by the pixels. Such algorithms are good at re-creating lost information, but they are not perfect. Real surface structures may have been lost completely, while false features that do not exist in reality may have been added.
The only way to find out how the comet surface really looks like is to get closer – and in a short while Rosetta will be much closer to the comet!
The scientific imaging system OSIRIS was built by a consortium led by the Max Planck Institute for Solar System Research (Germany) in collaboration with CISAS, University of Padova (Italy), the Laboratoire d’Astrophysique de Marseille (France), the Instituto de Astrofísica de Andalucia, CSIC (Spain), the Scientific Support Office of the European Space Agency (The Netherlands), the Instituto Nacional de Técnica Aeroespacial (Spain), the Universidad Politéchnica de Madrid (Spain), the Department of Physics and Astronomy of Uppsala University (Sweden), and the Institute of Computer and Network Engineering of the TU Braunschweig (Germany). OSIRIS was financially supported by the national funding agencies of Germany (DLR), France (CNES), Italy (ASI), Spain (MEC), and Sweden (SNSB) and the ESA Technical Directorate.