Dating craters

23-May-2019 01:45

Hollows are also some of the brightest and youngest features on Mercury’s surface.

Particularly high potassium concentrations were observed by MESSENGER's Gamma-Ray Spectrometer at high northern latitudes, as illustrated in the abundance map on the left side of the animation.In these global views, the Caloris impact basin is initially in the center, and the colors on the spinning globes represent the ratios by weight of magnesium to silicon and aluminum to silicon.Silicon is known to be relatively homogenous across the surface, so these maps demonstrate variations in the abundances of magnesium and aluminum, both of which are sensitive to the details of the interior melting that produced the lavas that formed the surface volcanic deposits.The first frame shows an Earth-based Arecibo radar image in red overlaid on a mosaic of MESSENGER’s Mercury Dual Imaging System images, enabling for the first time the identification of the host craters for all of the radar-bright deposits.The second frame shows the topography of the region as measured by MESSENGER’s Mercury Laser Altimeter (purple: about 5 km below average surface elevation; red: about 5 km above average surface elevation); illumination models derived from the topography show that the radar-bright deposits are located in regions of permanent shadow.

Particularly high potassium concentrations were observed by MESSENGER's Gamma-Ray Spectrometer at high northern latitudes, as illustrated in the abundance map on the left side of the animation.

In these global views, the Caloris impact basin is initially in the center, and the colors on the spinning globes represent the ratios by weight of magnesium to silicon and aluminum to silicon.

Silicon is known to be relatively homogenous across the surface, so these maps demonstrate variations in the abundances of magnesium and aluminum, both of which are sensitive to the details of the interior melting that produced the lavas that formed the surface volcanic deposits.

The first frame shows an Earth-based Arecibo radar image in red overlaid on a mosaic of MESSENGER’s Mercury Dual Imaging System images, enabling for the first time the identification of the host craters for all of the radar-bright deposits.

The second frame shows the topography of the region as measured by MESSENGER’s Mercury Laser Altimeter (purple: about 5 km below average surface elevation; red: about 5 km above average surface elevation); illumination models derived from the topography show that the radar-bright deposits are located in regions of permanent shadow.

The movie follows Angkor Vallis into the large crater Kofi (136 km diameter, centered at 56.74°N, 118.08°E), which has been flooded with lava.