This is Hebes Chasm on Mars. It forms a giant trough nearly 4.97 miles (8 km) deep, of Valles Marinera, the largest canyon system in the solar system. Taken with the High Resolution Stereo Camera on Mars Express.
Collapse in Hebes Chasma on Mars. The above image, taken by the robotic Mars Express spacecraft currently orbiting Mars, shows great details of the chasm and the unusual horseshoe shaped indentation in the central mesa. Material from the mesa appears to have flowed onto the floor of the chasm, while a possible dark layer appears to have pooled like ink on a downslope landing.
A new view of the famous Horsehead Nebula taken by the Hubble Space Telescope in infrared wavelengths. The nebula, shadowy in optical light, appears transparent and ethereal when seen in the infrared, represented here with visible shades.