Various shape models and 3D renderings of comet 67P can be seen at the websites maintained by Matthias Malmer and Greg Frieger. In particular, the Frieger site allows different shape models to be compared for 67P, and also shows the shape models for several other comets. Very soon, the MiARD project will have a new higher resolution shape model which will be displayed on this website, and probably also made available to others.
The Laboratoire d’Astrophysique de Marseille, one of the partners in the MiARD project, have just released this rendering of their digital terrain model of the Agilkia area of the comet where the Philae lander first touched down. The name Agilkia was selected by the European Space Agency from suggestions by the public, and is taken from the name of an island in the Nile river in Egypt.
The MiARD project has made a great deal of progress in refining the so-called ‘shape’ model of the comet, which is exactly what it sounds like – a mathematical representation of the shape of the comet, derived from photographs taken by the ROSETTA orbiter, together with navigational information. The example below shows the remarkable resolution now achieved.
NEIGHBOURHOOD OF THE AGILKIA LANDING SITE
This picture shows a rendered view of a high-resolution local digital terrain
model of the region in Ma’at around the Agilkia landing site, at which Philae
touched down the surface of the comet for the first time on Nov 12, 2014 at
The digital terrain model has been created in the frame of the MiARD project
with the “Multi-resolution Photoclinometry by Deformation” (MPCD) method
developed at Laboratoire d’Astrophysique de Marseille (CNRS, Aix-Marseille
University, France) using stereophotogrammetric data produced at the
German Aerospace Center (DLR, Berlin, Germany).
This view mimics the exact observing conditions of an image acquired by the
Narrow-Angle Camera onboard Rosetta on Nov 12, 2014 at 16:18 UTC, just after
the Philae touchdown. This image was acquired from a distance of about 15 km
above the surface, corresponding to a resolution of about 30 cm/pixel on
the image. The upper panel presents a global view of the DTM while the lower
panel is a zoom on the Agilkia landing site showing the footprints created by
Philae at the surface of the comet.
Fo rmore information, contact: email@example.com
The MiARD project partners at the Laboratoire d’Astrophysique de Marseille have been developing both qualitative and quantitative methods to compare the quality of shape models (digital terrain models) of the comet 67P/Churyumove-Gerasimenko. The image below shows two different provisional digital models of the comet (on the left the shape derived from stereo photoclinometry, on the right the shape derived from stereo photogrammetry). The centre image was obtained by the OSIRIS narrow angle camera on board the Rosetta spacecraft. These different images can be compared by eye to give a qualitative idea of the agreement. The datasets can be further processed to quantify the detail agreement (e.g. by looking at where edges are detected).
It should be noted that these small images do not give a true idea of the complexity and resolution of the datasets.