ALICE

The ALICE ultraviolet imaging spectrometer. Copyright ESA/AOES Medialab

ALICE is an Ultraviolet Imaging Spectrometer that will characterise the composition of the nucleus and coma and the nucleus/coma coupling of comet 67 P. The instrument is looking at spectral features at wavelengths in the ultra-violet (UV) range from 70 to 205 nm.

ALICE measures the abundances of noble gases (helium, neon, argon, krypton and xenon) in the coma in order to determine the temperature history of the comet. ALICE will also determine the production rates, variability, and structure of H₂O (water) and CO (carbon monoxide), and CO₂ (carbon dioxide) gas, 3 molecules vital for life. Finally, it will measure the abundance of carbon, hydrogen, oxygen, nitrogen and sulphur atoms within the comet’s coma.

ALICE was also involved in studying Mars, during the Mars flyby on 25 February 2007, and asteroid (21) Lutetia during the flyby on 10 July 2010

For further information visit:

• http://sci.esa.int/rosetta/35061-instruments/?fbodylongid=1636
• https://rosetta.jpl.nasa.gov/us-instruments/alice-overview
• http://alice.boulder.swri.edu/pages/introduction