PARIS, June 6 (UPI) -- A European spacecraft returned images of dramatic ancient flood events that carved channels over 600,000 square miles of the surface of Mars, scientists say.
The European Space agency released a mosaic this week made up of 67 images taken by its Mars Express orbiting spacecraft to mark the 10th anniversary of the orbiter's launch to the Red Planet.
The image mosaic shows the Kasei Valles, one of the largest outflow channel systems on Mars that from source to sink extends some 1,800 miles and descends by almost 2 miles in altitude.
The Kasei Valles has likely seen floods of many different sizes, astronomers said, brought about by the changing tectonic and volcanic activity in the nearby Tharsis region over 3 billion years ago.
Snow and ice melted by volcanic eruptions also likely contributed to torrential, muddy outpourings while glacial activity may have further shaped the channel system, they said.