Date Presented: September 29, 2011, at a NASA Press Briefing
Instrument: The Fast Imaging Plasma Spectrometer (FIPS)

Of Interest: This image is an artistic rendering of the global distribution of ionized sodium (Na) and helium (He) near the planet Mercury. Sodium exhibits distinct maxima near the magnetic cusps, where neutral atoms are likely liberated from the surface by solar wind ion bombardment. Helium is much more uniformly distributed, such as would be expected if the dominant source process were evaporation from a helium-saturated surface.

The MESSENGER spacecraft is the first ever to orbit the planet Mercury, and the spacecraft's seven scientific instruments and radio science investigation are unraveling the history and evolution of the Solar System's innermost planet. Visit the Why Mercury? section of this website to learn more about the key science questions that the MESSENGER mission is addressing. During the one-year primary mission, MDIS is scheduled to acquire more than 75,000 images in support of MESSENGER's science goals.

Credit: University of Michigan (inset courtesy AAAS/Science)

For information regarding the use of MESSENGER images, see the image use policy.