File:MESSENGER - MASCS.jpg

English: "Combining an ultraviolet spectrometer and infrared spectrograph, MASCS will measure the abundance of atmospheric gases around Mercury and detect minerals in its surface materials.

The Ultraviolet and Visible Spectrometer (UVVS) will determine the composition and structure of Mercury’s exosphere – the extremely low-density atmosphere – and study its neutral gas emissions. It will also search for and measure ionized atmospheric species. Together these measurements will help researchers understand the processes that generate and maintain the atmosphere, the connection between surface and atmospheric composition, the dynamics of volatile materials on and near Mercury, and the nature of the radar-reflective materials near the planet’s poles. The instrument has 25-kilometer altitude resolution at the planet’s limb.

Perched atop the ultraviolet spectrometer, the Visible and Infrared Spectrograph (VIRS) will measure the reflected visible and near-infrared light at wavelengths diagnostic of iron and titanium-bearing silicate materials on the surface, such as pyroxene, olivine, and ilmenite. The sensor’s best resolution is 3 kilometers at Mercury’s surface. "