An expert discusses the many ways that Alaska's arctic sea ice melt is affecting the lives of those who live in the area.
For more than twenty years, the Mars Express orbiter has studied the Red Planet and remains the European Space Agency's (ESA) only operational mission. In that time, it has provided the most complete map of the Martian atmosphere and its chemical composition. It has also studied Mars' innermost moon (Phobos) in stunning detail, and traced the flow channels, delta fans, and chaos terrain that demonstrate that liquid water once flowed on the planet's surface. In addition, the images taken by the orbiter have been used to create detailed mosaics that have breathtaking 3D views of the landscape.