Rosetta tracks Philae's cometary bouncedown
The European Space Agency (ESA) has released an image mosaic taken by the Rosetta mothership showing the Philae lander’s November 12 touchdown on comet 67P/Churyumov–Gerasimenko. The composite image shows the unmanned spacecraft making its approach to the surface of 67/P and its first rebound after its anchoring harpoons failed to deploy, along with timestamps in GMT (lander time) and images contrasting the touch sites before and after landing.
The mosaic was created using images taken over a 30 minute period using Rosetta’s OSIRIS narrow-angle camera from an altitude of about 15.5 km (9.6 mi) and at a resolution of 28 cm/pixel. According to ESA, the before and after images show an apparent dust cloud kicked up by Philae’s landing as well as the spacecraft’s shadow as it moved after its rebound to the East at 0.5 m/s (1.6 ft/s). This course was confirmed by the COmet Nucleus Sounding Experiment by Radiowave Transmission (CONSERT) experiment that measures radio waves between the lander and orbiter as they pass through the comet’s nucleus.
After its first bounce, Philae bounced a second time at 17:25 GMT before coming to rest at 17:32 GMT. The trouble is, no one knows exactly where. ESA hopes that by using the data from CONSERT, the Rosetta OSIRIS and navigation cameras, and the lander’s ROLIS and CIVA it will be possible to triangulate on the lander’s position.