A Craterful of Cracks

Here’s a view of a section of a crater on Mars filled with a lacework of bright spidery fractures, acquired on Sept. 20, 2015 with the HiRISE camera aboard NASA’s Mars Reconnaissance Orbiter. The crater is approximately 3 miles (5 km) wide and located in Mars’ north polar region, and its old, infilled interior has undergone countless millennia…

Here’s Our Best and Last Look at Pluto’s Moon-facing Side

Three days before New Horizons’ closest pass by Pluto and we already have the first final image of the mission: this is the last “best” view we will have of Pluto’s Charon-facing side, as the spacecraft will be acquiring its most detailed images of the planet’s opposite side on July 14. Pluto and its largest…

Mercury’s Special Scarps

The 300-mile-long long channel cutting across craters on Mercury in this image from MESSENGER was first identified in October of 2008, giving scientists clues to a geologic history found nowhere else in our solar system. Deep cracks like this, found all over the planet, are thought to be caused by the contraction of Mercury as…

Avalanche!

It’s always exciting to catch geologic surface events in action on Mars, reminding us that the red planet isn’t just a museum piece but a very active place! The image above is from the HiRISE camera on the Reconnaissance Orbiter showing dust clouds billowing up nearly 200 feet at the base of an ice cliff…

Slope Streaks

This image from the HiRISE camera aboard the Mars Reconnaissance Orbiter (MRO) shows streaks of dark-colored material lining the walls of a trough (left side) and tapering out onto its floor. One of the few currently active geologic processes on Mars, this streaking may be caused by finely-grained soil moving downhill in much the same…

Rivers of Sand

  Ripples and waves of sediment undulate around stone mesas in this high-resolution (false-color) photo of a crater in Mars’ Arabia Terra, a region at the boundary of highland and lowland. These eroded escarpments are thought to be the shores of an ancient ocean. Now all that laps against them are these serpentine sand dunes….