Ascraeus Mons from Mars Express (1 - ESA/ DLR/ FU Berlin - G. Neukum)

Due immagini in colori naturali del Vulcano Ascraeus Mons e dei suoi rilievi assolutamente affascinanti.
Ed eccoVi la Caption ESA originale:"This colour image shows a larger portion of the southern flank of Ascraeus Mons. The lighter, pink areas on the colour image, are clouds.
The visible lava tubes are caused by the crusting (or cooled lava) which occurs over a lava channel, a covering making the channel into a tunnel.
When lava production ceases, the tunnel empties and the roof of the tunnel falls in, making an elongated depression.
Occasionally, the depression forms a chain of small pits over an emptied lava tunnel. Pit chains and lava tunnels are common on the Martian surface and are also seen on other terrestrial planets and the Moon".