Plasma and magnetic field observations made during the near-Mercury parts of the orbit shown in Figure 3 in the Science Highlight article. The top panel shows proton plasma measurements from FIPS; the color scale denotes the total flux of these particles within a given interval of energy per charge. The second panel shows heavy ions within different ranges of mass per charge (m*), also measured by FIPS. The third panel shows MAG measurements of magnetic field strength. The bottom panel shows MESSENGER's altitude during passage near the planet, measured in units of Mercury's radius.

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.

Date Presented: June 21, 2011, in a MESSENGER Science Highlight article.

These images are from MESSENGER, a NASA Discovery mission to conduct the first orbital study of the innermost planet, Mercury. For information regarding the use of images, see the MESSENGER image use policy.