NASA's Planetary Data System (PDS) has released data collected from the MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) mission during its 37th through 42nd months in orbit about Mercury.

NASA requires that all of its planetary missions archive their data in the PDS, which makes available documented, peer-reviewed data to the research community. This 13th delivery from the MESSENGER team includes formatted raw and calibrated data collected through 17 September 2014 by the spacecraft's seven science instruments and the Radio Science investigation. Spacecraft, planet, instrument, camera-matrix, and events (SPICE) metadata from launch through the period of this release are also available.

The delivery includes new advanced products created from data acquired through March 17, 2014, encompassing the first six full Mercury solar days of MESSENGER orbital operations. Now available are global high-incidence east- and west-illumination maps and high-resolution regional targeted mosaics acquired by the Mercury Dual Imaging System (MDIS),

"Images for the global high-incidence maps were acquired when the Sun was very low on the horizon, which accentuates our view of surface topography because even small geologic features catch the Sun and cast long shadows," explained Brett Denevi, a planetary geologist at the Johns Hopkins University Applied Physics Laboratory (APL), in Laurel, Md., and the Deputy Instrument Scientist for MDIS.

"MDIS took images just after dawn and just before dusk, because asymmetrical features, such as thrust faults, are likely more visible in one illumination direction than the other. Moreover, crater walls and features that appear in shadow in one map will be illuminated in the other."

Creating the global maps, as with the high-incidence mosaics, requires a compromise, she explained. "In order to obtain coverage as close to global as possible, we have to sacrifice image resolution in many areas. These global maps are complemented by the regional targeted mosaics, which provide high-resolution images of selected sites of high scientific interest."

"The targets were chosen by the science team as areas for further investigation, and they have provided some of our most spectacular views of small-scale features such as hollows, fresh impact craters, and volcanic vents," she said. "In some cases these views are monochrome images acquired with the narrow-angle camera, and in others we opted for images acquired using the color filters of the slightly lower-resolution wide-angle camera."

This PDS also includes viewing normalizations, flux maps, and two-dimensional pitch-angle products from the Fast Imaging Plasma Spectrometer (FIPS) on the Energetic Particle and Plasma Spectrometer (EPPS) instrument.

"The new FIPS PDS data products simultaneously provide users with the most often used two-dimensional and three-dimensional data products, as well as the tools needed to create their own," explained Jim Raines, a space plasma physicist at the University of Michigan and FIPS Instrument Scientist.

"The new angular flux maps provide the best visualization of the direction that plasma ions are traveling in Mercury's space environment, which is a key quantity for understanding the behavior of the system. The new energy-resolved pitch-angle distributions give this information relative to the local magnetic field, which can be useful for identifying ions that are expected to impact Mercury's surface and cause space weathering."

"The viewing normalizations product contains the time-dependent rotation matrices needed for users to form their own versions of these and other multi-dimensional products, with arbitrary time accumulations,"� he added.