LOS ANGELES - Scientists say new images from space suggest Mars had a sizable lake on its surface billions of years ago.
Images taken by NASA's Mars Reconnaissance Orbiter show a 30-mile-long (50-kilometre-long) canyon and beach remnants surrounding a basin.
Researchers from the University of Colorado at Boulder estimate the lake, which probably formed 3.4 billion years ago, was 80 square miles and up to 1,500 feet (450 metres) deep.
The findings were published in this week's Geophysical Research Letters.
