— ESA (@esa) October 5, 2017
Launched on 2 June 2003, the Mars Express was Europe’s first planetary mission, named after the speed with which it was developed: only five years from mission approval to launch. At launch, the mission consisted of an orbiter and a lander. While approaching Mars in December 2003, the lander, Beagle 2, was released – but attempts to communicate with it after 25 December, the expected time of touch down, were unsuccessful. Consequently, the Beagle 2 mission was declared lost on 6 February 2004. However, the Mars Express orbiter started scientific observations as planned in January 2004. Originally planned for one Martian year (687 days), it has been in operation for more than 13 years, still sending to Earth valuable scientific data, as well as photographs of out-of-this-world beauty.
The latest pictures, released on 5 October, show a dune field in a crater.
According to the ESA website, what you see on the pictures is a dune field in an unnamed 48 km-wide impact crater in the southern highlands of Mars, which include:
“sickle-shaped dunes known as barchans, and parallel ridges of dunes called transverse dunes. A smoothly distributed sand sheet stretches between the dunes and the western wall of the crater. Barchans are the most common dune type found on Mars, and are also prevalent in Earth’s deserts. The shallower slope faces the wind, with the steeper, curved slope downwind, the ‘horns’ of the individual dunes pointing in the direction the wind is blowing. In this example, a southeasterly wind at the time of dune formation can be assumed.“
“The details of the central mesa inside Hebes Chasma are seen in close-up detail in this perspective view. A horseshoe-shaped chunk has been taken out of one side of the mound (left in this image); the material has slumped down onto the floor of the valley below. A dark patch appears to pool like spilt ink across the debris. It is most likely loose material that has slid down the walls from an intermediate layer. Melted ice could have played a role by weakening the rocks to create its flow-like appearance.
Along the side of the mound fine horizontal layering is seen. The layers likely comprise a mix of wind-blown dust and ancient lake sediments, along with remnants of the older plateau.”
“This computer-generated perspective view of part of the Promethei Terra highlands adjacent to Reull Vallis was created using data obtained from the High-Resolution Stereo Camera (HRSC) on ESA’s Mars Express. Centred at around 41°S and 107°E, the image has a ground resolution of about 16 m per pixel. The image shows a rounded and smooth-topped mountain with a large impact crater in the foreground. The crater is largely filled in with sediments and shows step-like structures towards the right side, possibly indicative of sublimation or evaporation of water ice at different times and at different depths within the crater.“
Hopefully, the Mars Express can hang on in orbit a while longer – the pictures are well worth it.