Reull Vallis is 1000 feet deep, scientists say A European spacecraft has captured a striking image of a river-like structure on Mars believed to have been formed when running water flowed in the distant martian past.A high-resolution stereo camera on the European Space Agency's [ESA] Mars Express orbiter photographed the 1,000-mile steep-sided channel running through the Promethei Terra Highlands, an ESA release said Thursday.
Dubbed the Reull Vallis, it is believed to have been created in Mars’ Hesperian period that ended between 3.5 and 1.89 billion years ago, scientists said.
The morphology of Reull Vallis suggests it has experienced a diverse and complex history, they said, with analogies seen in river and glacial activity on Earth.
The portion of the Reull Vallis captured in the Mars Express image is more than four miles wide and almost 1,000 feet deep, scientists said.
The images may by providing glimpses of a past on the Red Planet not too dissimilar to events on our own world today, they said.

Source: UPI