The APXS (Alpha Proton X-ray Spectrometer) is an experiment designed to determine the chemical composition of the Philae landing site. The instrument will be lowered to ~ 4 cm from the ground and will detect alpha particles and X-rays.
The data collected from the APXS system will be used to determine the chemical composition of the comet dust component. This will be compared with known meteorite compositions and put into context using data collected from other instruments on both the orbiter and lander.
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