Alice is any one of two ultraviolet imaging spectrometers; one used on the New Horizons spacecraft and the other used on the Rosetta spacecraft.[1] Alice is a small telescope with a spectrograph and a special detector with 32 pixels each with 1024 spectral channels detecting ultraviolet light.[2] Its primary role is to determine the relative concentrations of various elements and isotopes in Pluto's atmosphere.[3]
Alice has an off-axis telescope which sends light to a Rowland-circle spectrograph, and the instrument has a field of view of 6 degrees.[4] It is designed to capture airglow and solar occultation at the same time, and has two inputs to allow this.[4]