Supplementary material from "Identification of the Beagle 2 lander on Mars"

Abstract

The 2003 Beagle 2 Mars lander has been identified in Isidis Planitia at 90.43°E, 11.53°N, close to the predicted target of 90.50° E, 11.53° N. Beagle 2 was an exobiology lander designed to look for isotopic and compositional signs of life on Mars, as part of the ESA Mars Express (MEX) mission. The 2004 recalculation of the original landing ellipse from a 3-sigma major axis of 174–57 km, and the acquisition of Mars Reconnaissance Orbiter High Resolution Imaging Science Experiment (HiRISE) imagery at 30 cm per pixel across the target region, led to the initial identification of the lander in 2014. Following this, more HiRISE images, giving a total of 15, including IR, red and blue-green colours, were obtained over the area of interest and searched, which allowed the calculation of red : blue-green ratios and sub-pixel imaging using super-high-resolution techniques. The size (approx. 1.5 m), distinctive multilobed shape, red : blue-green average ratio of 1.0 distinct from the local Martian rocks, dust and soil (typically red : blue-green ratio of 2.1), and location close to the centre of the planned landing ellipse led to the identification of Beagle 2. The shape of the imaged lander, although to some extent masked by the specular reflections in the various images, is consistent with deployment of the lander lid and then some or all solar panels. Failure to fully deploy the panels—which may have been caused by damage during landing—would have prohibited communication between the lander and MEX and commencement of science operations. This implies that the main part of the entry, descent and landing sequence, the ejection from MEX, atmospheric entry and parachute deployment, and landing worked as planned with perhaps only the final full panel deployment failing.